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Sample records for field portable microchip

  1. Customized oligonucleotide microchips that convert multiple genetic information to simple patterns, are portable and reusable

    DOEpatents

    Mirzabekov, Andrei; Guschin, Dmitry Y.; Chik, Valentine; Drobyshev, Aleksei; Fotin, Alexander; Yershov, Gennadiy; Lysov, Yuri

    2002-01-01

    This invention relates to using customized oligonucleotide microchips as biosensors for the detection and identification of nucleic acids specific for different genes, organisms and/or individuals in the environment, in food and in biological samples. The microchips are designed to convert multiple bits of genetic information into simpler patterns of signals that are interpreted as a unit. Because of an improved method of hybridizing oligonucleotides from samples to microchips, microchips are reusable and transportable. For field study, portable laser or bar code scanners are suitable.

  2. Development of a Real-Time Microchip PCR System for Portable Plant Disease Diagnosis

    PubMed Central

    Kim, Hyun Soo; Cifci, Osman S.; Vaughn-Diaz, Vanessa L.; Ma, Bo; Kim, Sungman; Abdel-Raziq, Haron; Ong, Kevin; Jo, Young-Ki; Gross, Dennis C.; Shim, Won-Bo; Han, Arum

    2013-01-01

    Rapid and accurate detection of plant pathogens in the field is crucial to prevent the proliferation of infected crops. Polymerase chain reaction (PCR) process is the most reliable and accepted method for plant pathogen diagnosis, however current conventional PCR machines are not portable and require additional post-processing steps to detect the amplified DNA (amplicon) of pathogens. Real-time PCR can directly quantify the amplicon during the DNA amplification without the need for post processing, thus more suitable for field operations, however still takes time and require large instruments that are costly and not portable. Microchip PCR systems have emerged in the past decade to miniaturize conventional PCR systems and to reduce operation time and cost. Real-time microchip PCR systems have also emerged, but unfortunately all reported portable real-time microchip PCR systems require various auxiliary instruments. Here we present a stand-alone real-time microchip PCR system composed of a PCR reaction chamber microchip with integrated thin-film heater, a compact fluorescence detector to detect amplified DNA, a microcontroller to control the entire thermocycling operation with data acquisition capability, and a battery. The entire system is 25×16×8 cm3 in size and 843 g in weight. The disposable microchip requires only 8-µl sample volume and a single PCR run consumes 110 mAh of power. A DNA extraction protocol, notably without the use of liquid nitrogen, chemicals, and other large lab equipment, was developed for field operations. The developed real-time microchip PCR system and the DNA extraction protocol were used to successfully detect six different fungal and bacterial plant pathogens with 100% success rate to a detection limit of 5 ng/8 µl sample. PMID:24349341

  3. Engineering the bioelectrochemical interface using functional nanomaterials and microchip technique toward sensitive and portable electrochemical biosensors.

    PubMed

    Jia, Xiaofang; Dong, Shaojun; Wang, Erkang

    2016-02-15

    Electrochemical biosensors have played active roles at the forefront of bioanalysis because they have the potential to achieve sensitive, specific and low-cost detection of biomolecules and many others. Engineering the electrochemical sensing interface with functional nanomaterials leads to novel electrochemical biosensors with improved performances in terms of sensitivity, selectivity, stability and simplicity. Functional nanomaterials possess good conductivity, catalytic activity, biocompatibility and high surface area. Coupled with bio-recognition elements, these features can amplify signal transduction and biorecognition events, resulting in highly sensitive biosensing. Additionally, microfluidic electrochemical biosensors have attracted considerable attention on account of their miniature, portable and low-cost systems as well as high fabrication throughput and ease of scaleup. For example, electrochemical enzymetic biosensors and aptamer biosensors (aptasensors) based on the integrated microchip can be used for portable point-of-care diagnostics and environmental monitoring. This review is a summary of our recent progress in the field of electrochemical biosensors, including aptasensors, cytosensors, enzymatic biosensors and self-powered biosensors based on biofuel cells. We presented the advantages that functional nanomaterials and microfluidic chip technology bring to the electrochemical biosensors, together with future prospects and possible challenges.

  4. Design and operation of a portable scanner for high performance microchip capillary array electrophoresis.

    PubMed

    Scherer, James R; Liu, Peng; Mathies, Richard A

    2010-11-01

    We have developed a compact, laser-induced fluorescence detection scanner, the multichannel capillary array electrophoresis portable scanner (McCAEPs) as a platform for electrophoretic detection and control of high-throughput, integrated microfluidic devices for genetic and other analyses. The instrument contains a confocal optical system with a rotary objective for detecting four different fluorescence signals, a pneumatic system consisting of two pressure/vacuum pumps and 28 individual addressable solenoid valves for control of on-chip microvalves and micropumps, four Polymerase Chain Reaction (PCR) temperature control systems, and four high voltage power supplies for electrophoresis. The detection limit of the instrument is ~20 pM for on-chip capillary electrophoresis of fluorescein dyes. To demonstrate the system performance for forensic short tandem repeat (STR) analysis, two experiments were conducted: (i) electrophoretic separation and detection of STR samples on a 96-lane microfabricated capillary array electrophoresis microchip. Fully resolved PowerPlex(®) 16 STR profiles amplified from 1 ng of 9947A female standard DNA were successfully obtained; (ii) nine-plex STR amplification, sample injection, separation, and fluorescence detection of 100-copy 9948 male standard DNA in a single integrated PCR- capillary electrophoresis microchip. These results demonstrate that the McCAEPs can be used as a versatile control and detection instrument that operates integrated microfluidic devices for high-performance forensic human identification.

  5. Design and operation of a portable scanner for high performance microchip capillary array electrophoresis

    NASA Astrophysics Data System (ADS)

    Scherer, James R.; Liu, Peng; Mathies, Richard A.

    2010-11-01

    We have developed a compact, laser-induced fluorescence detection scanner, the multichannel capillary array electrophoresis portable scanner (McCAEPs) as a platform for electrophoretic detection and control of high-throughput, integrated microfluidic devices for genetic and other analyses. The instrument contains a confocal optical system with a rotary objective for detecting four different fluorescence signals, a pneumatic system consisting of two pressure/vacuum pumps and 28 individual addressable solenoid valves for control of on-chip microvalves and micropumps, four Polymerase Chain Reaction (PCR) temperature control systems, and four high voltage power supplies for electrophoresis. The detection limit of the instrument is ˜20 pM for on-chip capillary electrophoresis of fluorescein dyes. To demonstrate the system performance for forensic short tandem repeat (STR) analysis, two experiments were conducted: (i) electrophoretic separation and detection of STR samples on a 96-lane microfabricated capillary array electrophoresis microchip. Fully resolved PowerPlex® 16 STR profiles amplified from 1 ng of 9947A female standard DNA were successfully obtained; (ii) nine-plex STR amplification, sample injection, separation, and fluorescence detection of 100-copy 9948 male standard DNA in a single integrated PCR- capillary electrophoresis microchip. These results demonstrate that the McCAEPs can be used as a versatile control and detection instrument that operates integrated microfluidic devices for high-performance forensic human identification.

  6. Evaluation of a Portable Microchip Electrophoresis Fluorescence Detection System for the Analysis of Amino Acid Neurotransmitters in Brain Dialysis Samples.

    PubMed

    Oborny, Nathan J; Costa, Elton E Melo; Suntornsuk, Leena; Abreu, Fabiane C; Lunte, Susan M

    2016-01-01

    A portable fluorescence detection system for use with microchip electrophoresis was developed and compared to a benchtop system. Using this system, six neuroactive amines commonly found in brain dialysate (arginine, citrulline, taurine, histamine, glutamate, and aspartate) were derivatized offline with naphthalene-2,3-dicarboxaldehyde/cyanide, separated electrophoretically, and detected by fluorescence. The limits of detection for the analytes of interest were 50 - 250 nM for the benchtop system and 250 nM - 1.3 μM for the portable system, both of which were adequate for most analyte detection in brain microdialysis samples. The portable system was then demonstrated for the detection of the same six amines in a rat brain microdialysis sample.

  7. Low electric field DNA separation and in-channel amperometric detection by microchip capillary electrophoresis.

    PubMed

    Ghanim, Motasem Hilmi; Najimudin, Nazalan; Ibrahim, Kamarulazizi; Abdullah, Mohd Zaid

    2014-06-01

    Miniaturisation of microchip capillary electrophoresis (MCE) is becoming an increasingly important research topic, particularly in areas related to micro total analysis systems or lab on a chip. One of the important features associated with the miniaturised MCE system is the portable power supply unit. In this work, a very low electric field MCE utilising an amperometric detection scheme was designed for use in DNA separation. The device was fabricated from a glass/polydimethylsiloxane hybrid engraved microchannel with platinum electrodes sputtered onto a glass substrate. Measurement was based on a three-electrode arrangement, and separation was achieved using a very low electric field of 12 V/cm and sample volume of 1.5 µl. The device was tested using two commercial DNA markers of different base pair sizes. The results are in agreement with conventional electrophoresis, but with improved resolution. The sensitivity consistently higher than 100 nA, and the separation time approximately 45 min, making this microchip an ideal tool for DNA analysis.

  8. Microchip Capillary Electrophoresis with Electrochemical Detection for Monitoring Environmental Pollutants

    SciTech Connect

    Chen, Gang; Lin, Yuehe; Wang, Joseph

    2006-01-15

    This invited paper reviews recent advances and the key strategies in microchip capillary electrophoresis (CE) with electrochemical detection (ECD) for separating and detecting a variety of environmental pollutants. The subjects covered include the fabrication of microfluidic chips, sample pretreatments, ECD, typical applications of microchip CE with ECD in environmental analysis, and future prospects. It is expected that microchip CE-ECD will become a powerful tool in the environmental field and will lead to the creation of truly portable devices.

  9. Monitoring environmental pollutants by microchip capillary electrophoresis with electrochemical detection

    SciTech Connect

    Chen, Gang; Lin, Yuehe; Wang, Joseph

    2006-01-15

    This is a review article. During the past decade, significant progress in the development of miniaturized microfluidic systems has Occurred due to the numerous advantages of microchip analysis. This review focuses on recent advances and the key strategies in microchip capillary electrophoresis (CE) with electrochemical detection (ECD) for separating and detecting a variety of environmental pollutants. The subjects covered include the fabrication of microfluidic chips, ECD, typical applications of microchip CE with ECD in environmental analysis, and future prospects. It is expected that microchip CE-ECD will become a powerful tool in the environmental field and will lead to the creation of truly portable devices.

  10. Real-time forensic DNA analysis at a crime scene using a portable microchip analyzer.

    PubMed

    Liu, Peng; Yeung, Stephanie H I; Crenshaw, Karin A; Crouse, Cecelia A; Scherer, James R; Mathies, Richard A

    2008-09-01

    An integrated lab-on-a-chip system has been developed and successfully utilized for real-time forensic short tandem repeat (STR) analysis. The microdevice comprises a 160-nL polymerase chain reaction reactor with an on-chip heater and a temperature sensor for thermal cycling, microvalves for fluidic manipulation, a co-injector for sizing standard injection, and a 7-cm-long separation channel for capillary electrophoretic analysis. A 9-plex autosomal STR typing system consisting of amelogenin and eight combined DNA index system (CODIS) core STR loci has been constructed and optimized for this real-time human identification study. Reproducible STR profiles of control DNA samples are obtained in 2h and 30min with portable microsystem as well as its compatibility with crime scene investigation processes, real-time STR analyses were carried out at a mock crime scene prepared by the Palm Beach County Sheriff's Office (PBSO). Blood stain sample collection, DNA extraction, and STR analyses on the portable microsystem were conducted in the field, and a successful "mock" CODIS hit was generated on the suspect's sample within 6h. This demonstration of on-site STR analysis establishes the feasibility of real-time DNA typing to identify the contributor of probative biological evidence at a crime scene and for real-time human identification.

  11. Amperometric detection of carbohydrates with a portable silicone/quartz capillary microchip by designed fracture sampling.

    PubMed

    Zhai, Chun; Li, Chen; Qiang, Wei; Lei, Jianping; Yu, Xiaodong; Ju, Huangxian

    2007-12-15

    A silicone/quartz capillary microchip (SQCM) coupled with an ultranarrow sampling fracture was for the first time constructed without any micromachining. The SQCM could be used for direct determination of carbohydrates at a detection potential of +0.8 V (vs Ag/AgCl) with a copper microdisk electrode. The ultranarrow sampling fracture could be conveniently formed on a quartz capillary, which was fixed by a frame of poly(dimethylsiloxane) (PDMS). The designed fracture sampling suppressed the leakage of sample, thus simplifying the power supply. Furthermore, it thinned the sample plug for enhancing the resolution. The quartz capillary reduced the adsorption of analytes on the separation channel wall compared with a general PDMS microchip, thus enhanced the separation efficiency up to 239 000 plates/m for carbohydrates. This proposed system could satisfactorily separate eight carbohydrates within 180 s with good reproducibility and sensitively detect them in the linear ranges from 1 microM to 0.5 mM for trehalose and sucrose, 2.5 microM to 0.5 mM for lactose, galactose, glucose, and mannose, and 2.5 microM to 1.5 mM for fructose and xylose with the detection limit down to 90 amol. The designed microchip was successfully applied to detect carbohydrates in a practical acacia honey sample.

  12. Functionality of veterinary identification microchips following low- (0.5 tesla) and high-field (3 tesla) magnetic resonance imaging.

    PubMed

    Piesnack, Susann; Frame, Mairi E; Oechtering, Gerhard; Ludewig, Eberhard

    2013-01-01

    The ability to read patient identification microchips relies on the use of radiofrequency pulses. Since radiofrequency pulses also form an integral part of the magnetic resonance imaging (MRI) process, the possibility of loss of microchip function during MRI scanning is of concern. Previous clinical trials have shown microchip function to be unaffected by MR imaging using a field strength of 1 Tesla and 1.5. As veterinary MRI scanners range widely in field strength, this study was devised to determine whether exposure to lower or higher field strengths than 1 Tesla would affect the function of different types of microchip. In a phantom study, a total of 300 International Standards Organisation (ISO)-approved microchips (100 each of three different types: ISO FDX-B 1.4 × 9 mm, ISO FDX-B 2.12 × 12 mm, ISO HDX 3.8 × 23 mm) were tested in a low field (0.5) and a high field scanner (3.0 Tesla). A total of 50 microchips of each type were tested in each scanner. The phantom was composed of a fluid-filled freezer pack onto which a plastic pillow and a cardboard strip with affixed microchips were positioned. Following an MRI scan protocol simulating a head study, all of the microchips were accurately readable. Neither 0.5 nor 3 Tesla imaging affected microchip function in this study.

  13. Recent developments in electrochemical detection for microchip capillary electrophoresis.

    PubMed

    Vandaveer, Walter R; Pasas-Farmer, Stephanie A; Fischer, David J; Frankenfeld, Celeste N; Lunte, Susan M

    2004-11-01

    Significant progress in the development of miniaturized microfluidic systems has occurred since their inception over a decade ago. This is primarily due to the numerous advantages of microchip analysis, including the ability to analyze minute samples, speed of analysis, reduced cost and waste, and portability. This review focuses on recent developments in integrating electrochemical (EC) detection with microchip capillary electrophoresis (CE). These detection modes include amperometry, conductimetry, and potentiometry. EC detection is ideal for use with microchip CE systems because it can be easily miniaturized with no diminution in analytical performance. Advances in microchip format, electrode material and design, decoupling of the detector from the separation field, and integration of sample preparation, separation, and detection on-chip are discussed. Microchip CEEC applications for enzyme/immunoassays, clinical and environmental assays, as well as the detection of neurotransmitters are also described.

  14. Using microchip electrophoresis for real-time aerosol composition measurements: Field study results from San Gorgonio Wilderness, California

    NASA Astrophysics Data System (ADS)

    Evanoski-Cole, A. R.; Hecobian, A.; Lewis, G. S.; Hering, S. V.; Henry, C. S.; Collett, J. L.

    2012-12-01

    The detrimental impacts of atmospheric aerosol on human and ecosystem health, visibility and climate change have been studied extensively. However, the role of aerosol composition in these issues still needs further investigation due to the variability of aerosol particles over both time and space. The need for better temporal and spatial resolution of aerosol composition measurements is addressed in the development of a real-time instrument using microchip capillary electrophoresis. Termed Aerosol microChip Electrophoresis (ACE), this lab-on-a-chip instrument is inexpensive to manufacture, portable and provides sensitive real-time and semi-continuous aerosol composition measurements. A water condensation growth tube is used to enlarge water soluble aerosol particles with an aerodynamic diameter less than 2.5 μm. The aqueous sample is continuously collected by impaction into a sample reservoir on a custom designed microchip. A rapid separation of select aerosol components is achieved using microchip capillary electrophoresis coupled with conductivity detection. Here we present data from a recent field campaign in the San Gorgonio Wilderness in south western California. This unique high elevation wilderness site located to the east of the heavily populated cities of San Bernardino and Los Angeles provides a contrast of both clean background and aged urban aerosol as dictated by the meteorological conditions at the site. Ambient aerosol particles were continuously collected at a flow rate of 0.7 L/min into a liquid sample with a volume of 16.7 μL and then analyzed for sulfate, nitrate, chloride and oxalate every 48 seconds. When comparing the ambient concentrations with the meteorological conditions, the most notable trend was high nitrate and sulfate concentrations in ambient aerosol during upslope wind events, with values reaching as high as 34 and 5 μg/m3, respectively. Comparison aerosol composition measurements from filter samples and a particle

  15. Field portable XRF analysis of environmental samples.

    PubMed

    Kalnicky, D J; Singhvi, R

    2001-05-01

    One of the critical factors for successfully conducting contamination characterization, removal, and remedial operations at hazardous waste sites is rapid and appropriate response to analyze samples in a timely fashion. Turnaround time associated with off-site analysis is often too slow to support efficient utilization of the data. Field portable X-ray fluorescence (FPXRF) techniques provide viable and effective analytical approaches to meet on-site analysis needs for many types of environmental samples. Applications include the in situ analysis of metals in soils and sediments, thin films/particulates, and lead in paint.

  16. Field-portable lensfree tomographic microscope†

    PubMed Central

    Isikman, Serhan O.; Bishara, Waheb; Sikora, Uzair; Yaglidere, Oguzhan; Yeah, John; Ozcan, Aydogan

    2011-01-01

    We present a field-portable lensfree tomographic microscope, which can achieve sectional imaging of a large volume (~20 mm3) on a chip with an axial resolution of <7 μm. In this compact tomographic imaging platform (weighing only ~110 grams), 24 light-emitting diodes (LEDs) that are each butt-coupled to a fibre-optic waveguide are controlled through a cost-effective micro-processor to sequentially illuminate the sample from different angles to record lensfree holograms of the sample that is placed on the top of a digital sensor array. In order to generate pixel super-resolved (SR) lensfree holograms and hence digitally improve the achievable lateral resolution, multiple sub-pixel shifted holograms are recorded at each illumination angle by electromagnetically actuating the fibre-optic waveguides using compact coils and magnets. These SR projection holograms obtained over an angular range of ~50° are rapidly reconstructed to yield projection images of the sample, which can then be back-projected to compute tomograms of the objects on the sensor-chip. The performance of this compact and light-weight lensfree tomographic microscope is validated by imaging micro-beads of different dimensions as well as a Hymenolepis nana egg, which is an infectious parasitic flatworm. Achieving a decent three-dimensional spatial resolution, this field-portable on-chip optical tomographic microscope might provide a useful toolset for telemedicine and high-throughput imaging applications in resource-poor settings. PMID:21573311

  17. Development of field portable sampling and analysis systems

    SciTech Connect

    Beals, D.

    2000-06-08

    A rapid field portable sample and analysis system has been demonstrated at the Savannah River Site and the Hanford Site. The portable system can be used when rapid decisions are needed in the field during scoping or remediation activities, or when it is impractical to bring large volumes of water to the lab for analysis.

  18. Analyzing Microchips With Dark-Field Negative Photomicrography

    NASA Technical Reports Server (NTRS)

    Suszko, S. F.

    1985-01-01

    Inverse development process yields fine details. Photomicrographic technique produces images of integrated-circuit chips. Technique based on dark-field illumination: (chip lit with bright central spot of light and photographed by light scattered or diffracted from spot. Reveals more about microstructure patterns related to photoresist masking than more conventional bright-field method.

  19. Fabrication of a microfluidic Ag/AgCl reference electrode and its application for portable and disposable electrochemical microchips.

    PubMed

    Zhou, Jianhua; Ren, Kangning; Zheng, Yizhe; Su, Jing; Zhao, Yihua; Ryan, Declan; Wu, Hongkai

    2010-09-01

    This report describes a convenient method for the fabrication of a miniaturized, reliable Ag/AgCl reference electrode with nanofluidic channels acting as a salt bridge that can be easily integrated into microfluidic chips. The Ag/AgCl reference electrode shows high stability with millivolt variations. We demonstrated the application of this reference electrode in a portable microfluidic chip that is connected to a USB-port microelectrochemical station and to a computer for data collection and analysis. The low fabrication cost of the chip with the potential for mass production makes it disposable and an excellent candidate for real-world analysis and measurement. We used the chip to quantitatively analyze the concentrations of heavy metal ions (Cd(2+) and Pb(2+)) in sea water. We believe that the Ag/AgCl reference microelectrode and the portable electrochemical system will be of interest to people in microfluidics, environmental science, clinical diagnostics, and food research.

  20. Real-World Physics: A Portable MBL for Field Measurements.

    ERIC Educational Resources Information Center

    Albergotti, Clifton

    1994-01-01

    Uses a moderately priced digital multimeter that has output and software compatible with personal computers to make a portable, computer-based data-acquisition system. The system can measure voltage, current, frequency, capacitance, transistor hFE, and temperature. Describes field measures of velocity, acceleration, and temperature as function of…

  1. SITE EVALUATION OF FIELD PORTABLE PENTACHLOROPHENOL IMMUNOASSAYS

    EPA Science Inventory

    Four pentachlorophenol (PCP) enzyme immunoassays for environmental analysis have been evaluated through the U.S. EPA Superfund Innovative Technology Evaluation (SITE) program. Three assays were formatted for on-site field use and one assay could be used in a field laboratory sett...

  2. How to adapt portable computers for field gaugers

    SciTech Connect

    Cain, S. )

    1990-12-01

    Problems to be solved in using portable computers for field gaugers include developing the proper software and selecting the proper hardware. This article discusses software development and the considerations surrounding the selection of the hardware suitable to field gaugers. There are six state of development discussed. Software development is largely a process of communicating information about the eventual program and translating this information from one form to another.

  3. Portable Radiometer Identifies Minerals in the Field

    NASA Technical Reports Server (NTRS)

    Goetz, A. F. H.; Machida, R. A.

    1982-01-01

    Hand-held optical instrument aids in identifying minerals in field. Can be used in exploration for minerals on foot or by aircraft. The radiometer is especially suitable for identifying clay and carbonate minerals. Radiometer measures reflectances of mineral at two wavelengths, computes ratio of reflectances, and displays ratio to user.

  4. Portable field spectrometer for reflectance measurements 340-2500 nm.

    PubMed

    Myrabø, H K; Lillesaeter, O; Høimyr, T

    1982-08-01

    A portable field spectrometer designed for measuring the spectral reflectance signatures of terrain objects is described. The instrument employs a chopping technique rendering possible the simultaneous measurement of irradiance from sun and sky on one hand and radiance from the scene on the other. This enhances the applicability of the instrument during variable irradiance conditions caused by drifting clouds. The instrument operates over the 340-2500-nm spectral region. Examples of measuring results are given.

  5. Microchip capillary gel electrophoresis using programmed field strength gradients for the ultra-fast analysis of genetically modified organisms in soybeans.

    PubMed

    Kim, Yun-Jeong; Chae, Joon-Seok; Chang, Jun Keun; Kang, Seong Ho

    2005-08-12

    We have developed a novel method for the ultra-fast analysis of genetically modified organisms (GMOs) in soybeans by microchip capillary gel electrophoresis (MCGE) using programmed field strength gradients (PFSG) in a conventional glass double-T microchip. Under the programmed electric field strength and 0.3% poly(ethylene oxide) sieving matrix, the GMO in soybeans was analyzed within only 11 s of the microchip. The MCGE-PFSG method was a program that changes the electric field strength during GMO analysis, and was also applied to the ultra-fast analysis of PCR products. Compared to MCGE using a conventional and constantly applied electric field, the MCGE-PFSG analysis generated faster results without the loss of resolving power and reproducibility for specific DNA fragments (100- and 250-bp DNA) of GM-soybeans. The MCGE-PFSG technique may prove to be a new tool in the GMO analysis due to its speed, simplicity, and high efficiency.

  6. Field Testing of a Portable Radiation Detector and Mapping System

    SciTech Connect

    Hofstetter, K.J.; Hayes, D.W.; Eakle, R.F.

    1998-03-01

    Researchers at the Savannah River Site (SRS) have developed a man- portable radiation detector and mapping system (RADMAPS) which integrates the accumulation of radiation information with precise ground locations. RADMAPS provides field personnel with the ability to detect, locate, and characterize nuclear material at a site or facility by analyzing the gamma or neutron spectra and correlating them with position. the man-portable field unit records gamma or neutron count rate information and its location, along with date and time, using an embedded Global Positioning System (GPS). RADMAPS is an advancement in data fusion, integrating several off-the-shelf technologies with new computer software resulting in a system that is simple to deploy and provides information useful to field personnel in an easily understandable form. Decisions on subsequent actions can be made in the field to efficiently use available field resources. The technologies employed in this system include: recording GPS, radiation detection (typically scintillation detectors), pulse height analysis, analog-to-digital converters, removable solid-state (Flash or SRAM) memory cards, Geographic Information System (GIS) software and personal computers with CD-ROM supporting digital base maps. RADMAPS includes several field deployable data acquisition systems designed to simultaneously record radiation and geographic positions. This paper summarizes the capabilities of RADMAPS and some of the results of field tests performed with the system.

  7. Field-portable pixel super-resolution colour microscope.

    PubMed

    Greenbaum, Alon; Akbari, Najva; Feizi, Alborz; Luo, Wei; Ozcan, Aydogan

    2013-01-01

    Based on partially-coherent digital in-line holography, we report a field-portable microscope that can render lensfree colour images over a wide field-of-view of e.g., >20 mm(2). This computational holographic microscope weighs less than 145 grams with dimensions smaller than 17×6×5 cm, making it especially suitable for field settings and point-of-care use. In this lensfree imaging design, we merged a colorization algorithm with a source shifting based multi-height pixel super-resolution technique to mitigate 'rainbow' like colour artefacts that are typical in holographic imaging. This image processing scheme is based on transforming the colour components of an RGB image into YUV colour space, which separates colour information from brightness component of an image. The resolution of our super-resolution colour microscope was characterized using a USAF test chart to confirm sub-micron spatial resolution, even for reconstructions that employ multi-height phase recovery to handle dense and connected objects. To further demonstrate the performance of this colour microscope Papanicolaou (Pap) smears were also successfully imaged. This field-portable and wide-field computational colour microscope could be useful for tele-medicine applications in resource poor settings.

  8. A Field Portable Hyperspectral Goniometer for Coastal Characterization

    NASA Technical Reports Server (NTRS)

    Bachmann, Charles M.; Gray, Deric; Abelev, Andrei; Philpot, William; Fusina, Robert A.; Musser, Joseph A.; Vermillion, Michael; Doctor, Katarina; White, Maurice; Georgiev, Georgi

    2012-01-01

    During an airborne multi-sensor remote sensing experiment at the Virginia Coast Reserve (VCR) Long Term Ecological Research (LTER) site in June 2011 (VCR '11), first measurements were taken with the new NRL Goniometer for Outdoor Portable Hyperspectral Earth Reflectance (GOPHER). GOPHER measures the angular distribution of hyperspectral reflectance. GOPHER was constructed for NRL by Spectra Vista Corporation (SVC) and the University of Lethbridge through a capital equipment purchase in 2010. The GOPHER spectrometer is an SVC HR -1024, which measures hyperspectral reflectance over the range from 350 -2500 nm, the visible, near infrared, and short-wave infrared. During measurements, the spectrometer travels along a zenith quarter -arc track that can rotate in azimuth, allowing for measurement of the bi-directional reflectance distribution function (BRDF) over the whole hemisphere. The zenith arc has a radius of approximately 2m, and the spectrometer scan pattern can be programmed on the fly during calibration and validation efforts. The spectrometer and zenith arc assembly can be raised and lowered along a mast to allow for measurement of uneven terrain or vegetation canopies of moderate height. Hydraulics on the chassis allow for leveling of the instrument in the field. At just over 400 lbs, GOPHER is a field portable instrument and can be transformed into a compact trailer assembly for movement over long distances in the field.

  9. Development of a portable field monitor for PCBs. Final report

    SciTech Connect

    Bostick, W.D.; Denton, M.S.; Dinsmore, S.R.

    1983-01-01

    With the advent of recent regulations and those yet pending concerning allowable concentrations of polychlorinated biphenyls (PCBs), personnel in all aspects of the electric power industry, analytical support personnel, and those in the regulatory functions themselves have realized that the PCB problem, as well as these associated regulations, has far surpassed available monitoring capability. In short, detailed, stringent regulations are being set for contamination levels where no accepted ASTM procedure or instrumentation exists. The largest PCB problems occur in the form of PCB-contaminated oil in field transformers and storage containers, and pure askarel in transformers and capacitors. The most immediate need for a portable field instrument would be for use under PCB spill conditions. Portable monitors based on the principles of photoionization detection (PID) and infrared spectroscopy (IR) have been adapted and evaluated for this purpose. The latter includes both flow cell and horizontal multiple internal reflectance (HMIR) sampling configurations. Extensive work has also been performed on solvent-solvent and solvent-soil extractions, as well as PCB adsorption on packings, for use under spill conditions.

  10. A next generation field-portable goniometer system

    NASA Astrophysics Data System (ADS)

    Harms, Justin D.; Bachmann, Charles M.; Faulring, Jason W.; Ruiz Torres, Andres J.

    2016-05-01

    Various field portable goniometers have been designed to capture in-situ measurements of a materials bi-directional reflectance distribution function (BRDF), each with a specific scientific purpose in mind.1-4 The Rochester Institute of Technology's (RIT) Chester F. Carlson Center for Imaging Science recently created a novel instrument incorporating a wide variety of features into one compact apparatus in order to obtain very high accuracy BRDFs of short vegetation and sediments, even in undesirable conditions and austere environments. This next generation system integrates a dual-view design using two VNIR/SWIR pectroradiometers to capture target reflected radiance, as well as incoming radiance, to provide for better optical accuracy when measuring in non-ideal atmospheric conditions or when background illumination effects are non-negligible. The new, fully automated device also features a laser range finder to construct a surface roughness model of the target being measured, which enables the user to include inclination information into BRDF post-processing and further allows for roughness effects to be better studied for radiative transfer modeling. The highly portable design features automatic leveling, a precision engineered frame, and a variable measurement plane that allow for BRDF measurements on rugged, un-even terrain while still maintaining true angular measurements with respect to the target, all without sacrificing measurement speed. Despite the expanded capabilities and dual sensor suite, the system weighs less than 75 kg, which allows for excellent mobility and data collection on soft, silty clay or fine sand.

  11. Precise determination of nonlinear function of ion mobility for explosives and drugs at high electric fields for microchip FAIMS.

    PubMed

    Guo, Dapeng; Wang, Yonghuan; Li, Lingfeng; Wang, Xiaozhi; Luo, Jikui

    2015-01-01

    High-field asymmetric waveform ion mobility spectrometry (FAIMS) separates ions by utilizing the characteristics of nonlinear ion mobility at high and low electric fields. Accurate ion discrimination depends on the precise solution of nonlinear relationships and is essential for accurate identification of ion species for applications. So far, all the nonlinear relationships of ion mobility obtained are based at low electric fields (E/N <65 Td). Microchip FAIMS (μ-FAIMS) with small dimensions has high electric field up to E/N = 250 Td, making the approximation methods and conclusions for nonlinear relationships inappropriate for these systems. In this paper, we deduced nonlinear functions based on the first principle and a general model. Furthermore we considered the hydrodynamics of gas flow through microchannels. We then calculated the specific alpha coefficients for cocaine, morphine, HMX, TNT and RDX, respectively, based on their FAIMS spectra measured by μ-FAIMS system at ultra-high fields up to 250 Td. The results show that there is no difference in nonlinear alpha functions obtained by the approximation and new method at low field (<120 Td), but the error induced by using approximation method increases monotonically with the increase in field, and could be as much as 30% at a field of 250 Td.

  12. A portable microchip for ultrasensitive and high-throughput assay of thrombin by rolling circle amplification and hemin/G-quadruplex system.

    PubMed

    Lin, Xuexia; Chen, Qiushui; Liu, Wu; Li, Haifang; Lin, Jin-Ming

    2014-06-15

    In this work, a convenient and high-throughput colorimetric assay was developed on an aptamer-modified microchip for ultrasensitive detection of thrombin using rolling circle amplification and G-quadruplex DNAzyme. This system consisted of an aptamer-modified microchip and a secondary aptamer. The secondary aptamer contained a thrombin aptamer and a primer with a G-quadruplex circular template. RCA technology was used to improve the sensitivity by producing the multiple G-quadruplex units. To generate colorimetric signal, G-quadruplex DNAzyme was used to catalyze the H2O2-mediated oxidation of 2,2'-azinobis (3-ethylbenzothiozoline)-6-sulfonic acid. At the optimal conditions, the linear range for thrombin was 0.100-50.000 pg/mL, and the limit of detection was down to 0.083 pg/mL. Moreover, the developed method was successfully applied to detect thrombin from human plasma and serum, indicating that this approach has great potential in clinical diagnosis and medical investigation.

  13. A Portable, Field-Deployable Analyzer for Isotopic Water Measurements

    NASA Astrophysics Data System (ADS)

    Berman, E. S.; Gupta, M.; Huang, Y. W.; Lacelle, D.; McKay, C. P.; Fortson, S.

    2015-12-01

    Water stable isotopes have for many years been used to study the hydrological cycle, catchment hydrology, and polar climate among other applications. Typically, discrete water samples are collected and transported to a laboratory for isotope analysis. Due to the expense and labor associated with such sampling, isotope studies have generally been limited in scope and time-resolution. Field sampling of water isotopes has been shown in recent years to provide dense data sets with the increased time resolution illuminating substantially greater short term variability than is generally observed during discrete sampling. A truly portable instrument also opens the possibility to utilize the instrument as a tool for identifying which water samples would be particularly interesting for further laboratory investigation. To make possible such field measurements of liquid water isotopes, Los Gatos Research has developed a miniaturized, field-deployable liquid water isotope analyzer. The prototype miniature liquid water isotope analyzer (mini-LWIA) uses LGR's patented Off-Axis ICOS (Integrated Cavity Output Spectroscopy) technology in a rugged, Pelican case housing for easy transport and field operations. The analyzer simultaneously measures both δ2H and δ18O from liquid water, with both manual and automatic water introduction options. The laboratory precision for δ2H is 0.6 ‰, and for δ18O is 0.3 ‰. The mini-LWIA was deployed in the high Arctic during the summer of 2015 at Inuvik in the Canadian Northwest Territories. Samples were collected from Sachs Harbor, on the southwest coast of Banks Island, including buried basal ice from the Lurentide Ice Sheet, some ice wedges, and other types of ground ice. Methodology and water analysis results from this extreme field deployment will be presented.

  14. Detection of hazardous chemicals using field-portable Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Wright, Cherylyn W.; Harvey, Scott D.; Wright, Bob W.

    2003-07-01

    A major challenge confronting emergency response, border control, and other security-related functions is the accurate, rapid, and safe identification of potentially hazardous chemicals outside a laboratory environment. Raman spectroscopy is a rapid, non-intrusive technique that can be used to confidently identify many classes of hazardous and potentially explosive compounds based on molecular vibration information. Advances in instrumentation now allow reliable field - portable measurements to be made. Before the Raman technique can be effectively applied and be accepted within the scientific community, realistic studies must be performed to develop methods, define limitations, and rigorously evaluate its effectiveness. Examples of a variety of chemicals (including neat and diluted chemical warfare [CW] agents, a CW agent precursor, a biological warfare (BW)-related compound, an illicit drug, and explosives) identified using Raman spectroscopy in various types of containers and on surfaces are given, as well as results from a blind field test of 29 unknown samples which included CW agent precursors and/or degradation products, solvents associated with CW agent production, pesticides, explosives, and BW toxins (mostly mycotoxins). Additionally, results of experimental studies to evaluate the analysis of flammable organic solvents, propellants, military explosives, mixtures containing military explosives, shock-sensitive explosives, and gun powders are described with safety guidelines. Spectral masks for screening unknown samples for explosives and nerve agents are given.

  15. Microchips in Medicine: Current and Future Applications.

    PubMed

    Eltorai, Adam E M; Fox, Henry; McGurrin, Emily; Guang, Stephanie

    2016-01-01

    With the objective of improving efficacy and morbidity, device manufacturers incorporate chemicals or drugs into medical implants. Using multiple reservoirs of discrete drug doses, microchips represent a new technology capable of on-demand release of various drugs over long periods of time. Herein, we review drug delivery systems, how microchips work, recent investigations, and future applications in various fields of medicine.

  16. Microchips in Medicine: Current and Future Applications

    PubMed Central

    Eltorai, Adam E. M.; Fox, Henry; McGurrin, Emily; Guang, Stephanie

    2016-01-01

    With the objective of improving efficacy and morbidity, device manufacturers incorporate chemicals or drugs into medical implants. Using multiple reservoirs of discrete drug doses, microchips represent a new technology capable of on-demand release of various drugs over long periods of time. Herein, we review drug delivery systems, how microchips work, recent investigations, and future applications in various fields of medicine. PMID:27376079

  17. Portable narcotics detector and the results obtained in field tests

    NASA Astrophysics Data System (ADS)

    Tumer, Tumay O.; Su, Chih-Wu; Kaplan, Christopher R.; Rigdon, Stephen W.

    1997-02-01

    A compact integrated narcotics detection instrument (CINDI) has been developed at NOVA R&D, Inc. with funding provided by the U.S. Coast Guard. CINDI is designed as a portable sensitive neutron backscatter detector which has excellent penetration for thick and high Z compartment barriers. It also has a highly sensitive detection system for backscattered neutrons and, therefore, uses a very weak californium-252 neutron source. Neutrons backscatter profusely from materials that have a large hydrogen content, such as narcotics. The rate of backscattered neutrons detected is analyzed by a microprocessor and displayed on the control panel. The operator guides the detector along a suspected area and displays in real time the backscattered neutron rate. CINDI is capable of detecting narcotics effectively behind panels made of steel, wood, fiberglass, or even lead-lined materials. This makes it useful for inspecting marine vessels, ship bulkheads, automobiles, structure walls or small sealed containers. The strong response of CINDI to hydrogen-rich materials such as narcotics makes it an effective tool for detecting concealed drugs. Its response has been field tested by NOVA, the U.S. Coast Guard and Brewt Power Systems. The results of the tests show excellent response and specificity to narcotic drugs. Several large shipments of concealed drugs have been discovered during these trials and the results are presented and discussed.

  18. Technology assessment of field portable instrumentation for use at Rocky Mountain Arsenal: Final report

    SciTech Connect

    Jenkins, R.A.; Maskarinec, M.P.; Griest, W.H.; Dyer, F.F.; Moody, R.L.; Buchanan, M.V.

    1988-03-01

    An assessment was made of commercially available field instrumentation for analysis of samples at Rocky Mountain Arsenal. The analytes considered were metals, volatile organics, and semivolatile organics. Colorimetrics tests for metals are recommended for screening, with positives being confirmed by microwave digestion followed by portable atomic absorption. A portable mercury monitor is recommended for this analysis. Portable x-ray fluorescence is recommended for higher levels of inorganics. For volatile organics, purge and trap and heated headspace followed by portable gas chromatography are recommended. For semivolatiles in soil, SOXTEC extraction and gas or thin layer chromatography are recommended. For semivolatiles is water, solvent extraction using a MIXXOR is recommended. 1 fig., 13 tabs.

  19. [Development of innovative methods of electromagnetic field evaluation for portable radio-station].

    PubMed

    Rubtsova, N B; Perov, S Iu; Bogacheva, E V; Kuster, N

    2013-01-01

    The results of portable radio-station "Radiy-301" electromagnetic fields (EMF) emission measurement and specific absorption rate data evaluation has shown that workers' exposure EMF levels may elevate hygienic norms and hereupon can be health risk factor. Possible way of portable radio-station EMF dosimetry enhancement by means of domestic and international approaches harmonization is considered.

  20. Barcoded microchips for biomolecular assays.

    PubMed

    Zhang, Yi; Sun, Jiashu; Zou, Yu; Chen, Wenwen; Zhang, Wei; Xi, Jianzhong Jeff; Jiang, Xingyu

    2015-01-20

    Multiplexed assay of analytes is of great importance for clinical diagnostics and other analytical applications. Barcode-based bioassays with the ability to encode and decode may realize this goal in a straightforward and consistent manner. We present here a microfluidic barcoded chip containing several sets of microchannels with different widths, imitating the commonly used barcode. A single barcoded microchip can carry out tens of individual protein/nucleic acid assays (encode) and immediately yield all assay results by a portable barcode reader or a smartphone (decode). The applicability of a barcoded microchip is demonstrated by human immunodeficiency virus (HIV) immunoassays for simultaneous detection of three targets (anti-gp41 antibody, anti-gp120 antibody, and anti-gp36 antibody) from six human serum samples. We can also determine seven pathogen-specific oligonucleotides by a single chip containing both positive and negative controls.

  1. Portable Remote Imaging Spectrometer (PRISM): Laboratory and Field Calibration

    NASA Technical Reports Server (NTRS)

    Mouroulis, Pantazis; Van Gorp, Byron; Green, Robert O.; Eastwood, Michael; Boardman, Joseph; Richardson, Brandon S.; Rodriguez, Jose I.; Urquiza, Eugenio; Franklin, Brian D.; Gao, Bo-Cai

    2012-01-01

    We report the characteristics of the Portable Remote Imaging Spectrometer, an airborne sensor specifically designed for the challenges of coastal ocean research. PRISM has high signal to noise ratio and uniformity, as well as low polarization sensitivity. Acquisition of high quality data has been demonstrated with the first engineering flight.

  2. AN IMPROVED PORTABLE SURGICAL TABLE FOR THE FIELD AND LABORATORY

    EPA Science Inventory

    I substantially modified a portable surgical table design by Courtois (1981) to increase its durability and utility. The new design incorporated durable plastic components, a nonskid neoprene surgery surface, and surgical tool bins. The system was used to implant fish and amphibi...

  3. ENVIRONMENTAL TECHNOLOGY VERFICATION REPORT - FIELD PORTABLE X-RAY FLUORESCENCE ANALYZER - TN SPECTRACE, TN 9000 AND TN PB FIELD PORTABLE X-RAY FLOURESCENCE ANALYZERS

    EPA Science Inventory

    In April 1995, the U.S. Environmental Protection Agency (EPA) sponsored a demonstration of field portable X-ray fluorescence (FPXRF) analyzers. The primary objectives of this demonstration were to evaluate these analyzers for: (1) their analytical performance relative to standar...

  4. Tackling field-portable Raman spectroscopy of real world samples

    NASA Astrophysics Data System (ADS)

    Shand, Neil C.

    2008-10-01

    A major challenge confronting first responders, customs authorities and other security-related organisations is the accurate, rapid, and safe identification of potentially hazardous chemicals outside a laboratory environment. Currently, a range of hand portable Raman equipment is commercially available that is low cost and increasingly more sophisticated. These systems are generally based on the 785nm Stokes shifted Raman technique with many using dispersive grating spectrometers. This technique offers a broad range of capabilities including the ability to analyse illicit drugs, explosives, chemical weapons and pre-cursors but still has some fundamental constraints. 'Real world' samples, such as those found at a crime scene, will often not be presented in the most accessible manner. Simple issues such as glass fluorescence can make an otherwise tractable sample impossible to analyse in-situ. A new generation of portable Raman equipment is currently being developed to address these issues. Consideration is given to the use of longer wavelength for fluorescence reduction. Alternative optical designs are being tested to compensate for the signal reduction incurred by moving to longer wavelengths. Furthermore, the use of anti-Stokes spectroscopy is being considered as well as investigating the robustness and portability of traditional Fourier Transform interferometer designs along with future advances in detector technology and ultra small spectrometers.

  5. ANOLE Portable Radiation Detection System Field Test and Evaluation Campaign

    SciTech Connect

    Chris A. Hodge

    2007-07-12

    Handheld, backpack, and mobile sensors are elements of the Global Nuclear Detection System for the interdiction and control of illicit radiological and nuclear materials. They are used by the U.S. Department of Homeland Security (DHS) and other government agencies and organizations in various roles for border protection, law enforcement, and nonproliferation monitoring. In order to systematically document the operational performance of the common commercial off-the-shelf portable radiation detection systems, the DHS Domestic Nuclear Detection Office conducted a test and evaluation campaign conducted at the Nevada Test Site from January 18 to February 27, 2006. Named “Anole,” it was the first test of its kind in terms of technical design and test complexities. The Anole test results offer users information for selecting appropriate mission-specific portable radiation detection systems. The campaign also offered manufacturers the opportunity to submit their equipment for independent operationally relevant testing to subsequently improve their detector performance. This paper will present the design, execution, and methodologies of the DHS Anole portable radiation detection system test campaign.

  6. Microchip Analysis of Toxic Metal Ions in Support of DOE's EMSP

    SciTech Connect

    Collins, Greg E.; Lu, Qin; Deng, Gang

    2003-09-10

    The DoE currently has the daunting task of deactivating 7,000 contaminated buildings and decommissioning 900 contaminated buildings that remain from the United States' involvement in nuclear weapons development over the last 50 years. The Environmental Management team has highlighted the need for revolutionizing technologies capable of improving characterization, monitoring and certification of contaminated equipment and facilities with emphasis on real time characterization in the field. We will discuss our efforts to develop a portable, compact microchip capillary electrophoresis unit for rapid characterization and certification of ppb levels of surface and airborne toxic metal contaminants found or originating from scrap metal and building materials in real time within the field.

  7. Implementation of a Portable HPGe for Field Contamination Assay.

    PubMed

    Hayes, Robert Bruce

    2016-06-01

    Using MCNP to construct a detector model based initially on x-ray images of a portable high purity germanium (HPGe) detector followed by normalizing covering material values to also agree with check source responses, a validation of the model was attained. By calibrating the detector parameters using large count spectra, rigorous reproducibility is attained for high activity measurements but does not prevent deviations from normality in error distributions at the very low count events where spectral peaks are not always identifiable. The resulting model was created to allow operational assay of contamination over large areal distributions that could not otherwise be measured, such as the exhaust shaft at the Waste Isolation Pilot Plant (WIPP). Results indicate that contamination levels of activity in the exhaust shaft can be assayed to within a factor of 2. Detection limits are evaluated to be well below the contamination levels, which would constitute a legal environmental release if unfiltered ventilation of the underground facility were used.

  8. Sensitive determination of neurotransmitters in urine by microchip electrophoresis with multiple-concentration approaches combining field-amplified and reversed-field stacking.

    PubMed

    Zhang, Yan; Zhang, Yi; Wang, Guan; Chen, Wujuan; Li, Yi; Zhang, Yating; He, Pingang; Wang, Qingjiang

    2016-07-01

    Microchip electrophoresis (MCE) is particularly attractive as it provides high sensitivity and selectivity, short analysis time and low sample consumption. An on-line preconcentration strategy combining field-amplified stacking (FASS) and reversed-field stacking (RFS) was developed for efficient and sensitive analysis of neurotransmitters in real urine samples by MCE with laser induced fluorescence (LIF) detection. In this study, the multiple-preconcentration strategy greatly improves the sensitivity enhancement and surpass other conventional analytical methods for neurotransmitters detection. Under optimal conditions, the separation of three neurotransmitters (dopamine, norepinephrine and serotonin), was achieved within 3min with limits of detection (S/N=3) of 1.69, 2.35, and 2.73nM, respectively. The detection sensitivities were improved by 201-, 182-, and 292-fold enhancement, for the three neurotransmitters respectively. Other evaluation parameters such as linear correlation coefficients were considered as satisfactory. A real urine sample was analyzed with recoveries of 101.8-106.4%. The proposed FASS-RFS-MCE method was characterized in terms of precision, linearity, accuracy and successfully applied for rapid and sensitive determination of three neurotransmitters in human urine. PMID:27187932

  9. Sensitive determination of neurotransmitters in urine by microchip electrophoresis with multiple-concentration approaches combining field-amplified and reversed-field stacking.

    PubMed

    Zhang, Yan; Zhang, Yi; Wang, Guan; Chen, Wujuan; Li, Yi; Zhang, Yating; He, Pingang; Wang, Qingjiang

    2016-07-01

    Microchip electrophoresis (MCE) is particularly attractive as it provides high sensitivity and selectivity, short analysis time and low sample consumption. An on-line preconcentration strategy combining field-amplified stacking (FASS) and reversed-field stacking (RFS) was developed for efficient and sensitive analysis of neurotransmitters in real urine samples by MCE with laser induced fluorescence (LIF) detection. In this study, the multiple-preconcentration strategy greatly improves the sensitivity enhancement and surpass other conventional analytical methods for neurotransmitters detection. Under optimal conditions, the separation of three neurotransmitters (dopamine, norepinephrine and serotonin), was achieved within 3min with limits of detection (S/N=3) of 1.69, 2.35, and 2.73nM, respectively. The detection sensitivities were improved by 201-, 182-, and 292-fold enhancement, for the three neurotransmitters respectively. Other evaluation parameters such as linear correlation coefficients were considered as satisfactory. A real urine sample was analyzed with recoveries of 101.8-106.4%. The proposed FASS-RFS-MCE method was characterized in terms of precision, linearity, accuracy and successfully applied for rapid and sensitive determination of three neurotransmitters in human urine.

  10. Electric-field assisted immobilization and hybridization of DNA oligomers on thin-film microchips.

    PubMed

    Fixe, F; Branz, H M; Louro, N; Chu, V; Prazeres, D M F; Conde, J P

    2005-10-01

    Single, square voltage pulses in the microsecond timescale result in selective 5'-end covalent bonding (immobilization) of thiolated single-stranded (ss) DNA probes to a modified silicon dioxide flat surface and in specific hybridization of ssDNA targets to the immobilized probe. Immobilization and hybridization rates using microsecond voltage pulses at or below 1 V are at least 10(8) times faster than in the passive control reactions performed without electric field (E), and can be achieved with at least three differently functionalized thin-film surfaces on plastic or glass substrates. The systematic study of the effect of DNA probe and target concentrations, of DNA probe and target length, and the application of asymmetric pulses on E-assisted DNA immobilization and hybridization showed that: (1) the rapidly rising edge of the pulse is most critical to the E-assisted processes, but the duration of the pulse is also important; (2) E-assisted immobilization and hybridization can be performed with micrometre-sized pixels, proving the potential for use on microelectronic length scales, and the applied voltage can be scaled down together with the electrode spacing to as low as 25 mV; and (3) longer DNA chains reduce the yield in the E-assisted immobilization and hybridization because the density of physisorbed single-stranded DNA is reduced. The results show that the E-induced reactions can be used as a general method in DNA microarrays to produce high-density DNA chips (E-immobilization) and speed the microarray-based analysis (E-hybridization). PMID:20817972

  11. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT - FIELD PORTABLE X-RAY FLUORESCENCE ANALYZER - HNU SYSTEMS, SEFA-P

    EPA Science Inventory

    In April 1995, the Environmental Protection Agency (EPA) conducted a demonstration of field portable X-ray fluorescence (FPXRF) Analyzers. The primary objectives of this demonstration were (1) to determine how well FPXRF analyzers perform in comparison to a standard reference m...

  12. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT - FIELD PORTABLE X-RAY FLUORESCENCE ANALYZER - SCITEC, MAP SPECTRUM ANALYZER

    EPA Science Inventory

    In April 1995, the U.S. Environmental Protection Agency (EPA) sponsored a demonstration of field portable X-ray fluorescence (FPXRF) analyzers. The primary objectives of this demonstration were (1) to determine how well FPXRF analyzers perform in comparison to standard reference...

  13. TESTING, PERFORMANCE VALIDATION AND QUALITY ASSURANCE/QUALITY CONTROL OF FIELD-PORTABLE INSTRUMENTATION

    EPA Science Inventory

    New technologies for field-portable monitoring instruments often have a long lead time in development and authorization. Some obstacles to the acceptance of these pilot technologies include concern about liabilities, reluctance to take risks on new technologies, and uncertainty a...

  14. A Field-Portable X-Ray Fluorescence Instrument: Design and Applications

    NASA Astrophysics Data System (ADS)

    Civici, Nikolla

    2007-04-01

    The field portable XRF (FPXRF) spectrometer is composed of a measuring head that holds the detector (Si-PIN) and the excitation sources (Cd-109 and Am-241) and the spectrum acquisition system. The application of this system for the analysis of cultural heritage artifacts will be presented and discussed.

  15. CHARACTERIZATION OF CHROMIUM-CONTAMINATED SOILS USING FIELD-PORTABLE X-RAY FLUORESCENCE

    EPA Science Inventory

    A detailed characterization of the underlying and adjacent soils near a chrome plating shop utilized field-portable X- ray fluorescence (XRF) as a screening tool. XRF permitted real-time acquisition of estimates for total metal content of soils. A trailer-mounted soil coring unit...

  16. Integration of amperometric sensors for microchip capillary electrophoresis application

    NASA Astrophysics Data System (ADS)

    Dicorato, F.; Moore, E.; Glennon, J.

    2011-08-01

    Capillary electrophoresis is a technique for the separation and analysis of chemical compounds. Techniques adopted from the microchip technology knowledge have led to recent developments of electrophoresis system with integration on microchip. Microchip Capillary Electrophoresis (μCE) systems offer a series of advantages as easy integration for Lab-on-a-chip applications, high performance, portability, speed, minimal solvent and sample requirements. A new technological challenge aims at the development of an economic modular microchip capillary electrophoresis systems using separable and independent units concerning the sensor. In this project we worked on the development of an interchangeable amperometric sensor in order to provide a solution to such electrode passivation and facilitating the use of tailored sensors for specific analyte detection besides. Fluidic chips have been machined from cyclic olefin polymer pallets (Zeonor®) using a micro-injection molding machine.

  17. Particle-free microchip processing

    DOEpatents

    Geller, Anthony S.; Rader, Daniel J.

    1996-01-01

    Method and apparatus for reducing particulate contamination in microchip processing are disclosed. The method and apparatus comprise means to reduce particle velocity toward the wafer before the particles can be deposited on the wafer surface. A reactor using electric fields to reduce particle velocity and prevent particulate contamination is disclosed. A reactor using a porous showerhead to reduce particle velocities and prevent particulate contamination is disclosed.

  18. Particle-free microchip processing

    DOEpatents

    Geller, A.S.; Rader, D.J.

    1996-06-04

    Method and apparatus for reducing particulate contamination in microchip processing are disclosed. The method and apparatus comprise means to reduce particle velocity toward the wafer before the particles can be deposited on the wafer surface. A reactor using electric fields to reduce particle velocity and prevent particulate contamination is disclosed. A reactor using a porous showerhead to reduce particle velocities and prevent particulate contamination is disclosed. 5 figs.

  19. Downsizing with VXIbus - Opportunities and limitations in factory, field, and portable environments

    NASA Astrophysics Data System (ADS)

    Desjardin, Larry

    The author examines the technical constraints of downsizing for factory, field, and portable environments and develops metrics for comparing functional densities. Two examples of downsized VXIbus systems are evaluated. One is a C-size system with DC to microwave capability for factory floor or transportable ATE (automatic test equipment) applications. The second is a B-size system that is a lower performance equivalent of the C-size system with the microwave functionality removed; it is applicable for transportable and portable ATE. Actual examples of reduced-size test equipment ranging from battery operated testers to rack mounted, factory-based test systems are shown and evaluated. It is concluded that the VXIbus can deliver substantial reductions in test system size for factory, transportable, and portable ATE. Size reduction averages about 3 to 1 over equivalent HP-IB rack and stack instruments.

  20. General purpose, field-portable cell-based biosensor platform.

    PubMed

    Gilchrist, K H; Barker, V N; Fletcher, L E; DeBusschere, B D; Ghanouni, P; Giovangrandi, L; Kovacs, G T

    2001-09-01

    There are several groups of researchers developing cell-based biosensors for chemical and biological warfare agents based on electrophysiologic monitoring of cells. In order to transition such sensors from the laboratory to the field, a general-purpose hardware and software platform is required. This paper describes the design, implementation, and field-testing of such a system, consisting of cell-transport and data acquisition instruments. The cell-transport module is a self-contained, battery-powered instrument that allows various types of cell-based modules to be maintained at a preset temperature and ambient CO(2) level while in transit or in the field. The data acquisition module provides 32 channels of action potential amplification, filtering, and real-time data streaming to a laptop computer. At present, detailed analysis of the data acquired is carried out off-line, but sufficient computing power is available in the data acquisition module to enable the most useful algorithms to eventually be run real-time in the field. Both modules have sufficient internal power to permit realistic field-testing, such as the example presented in this paper. PMID:11544049

  1. A controlled-release microchip.

    PubMed

    Santini, J T; Cima, M J; Langer, R

    1999-01-28

    Much previous work in methods of achieving complex drug-release patterns has focused on pulsatile release from polymeric materials in response to specific stimuli, such as electric or magnetic fields, exposure to ultrasound, light or enzymes, and changes in pH or temperature. An alternative method for achieving pulsatile release involves using microfabrication technology to develop active devices that incorporate micrometre-scale pumps, valves and flow channels to deliver liquid solutions. Here we report a solid-state silicon microchip that can provide controlled release of single or multiple chemical substances on demand. The release mechanism is based on the electrochemical dissolution of thin anode membranes covering microreservoirs filled with chemicals in solid, liquid or gel form. We have conducted proof-of-principle release studies with a prototype microchip using gold and saline solution as a model electrode material and release medium, and we have demonstrated controlled, pulsatile release of chemical substances with this device.

  2. Portable Analyzer Based on Microfluidics/Nanoengineered Electrochemical Sensors for in Situ Characterization of Mixed Wastes

    SciTech Connect

    Wang, Joseph

    2006-06-01

    This research effort aims at developing a portable analytical system for fast, sensitive, and inexpensive, on-site monitoring of toxic transition metals and radionuclides in contaminated DOE Sites. The portable devices will be based on Microscale Total Analytical systems ( -TAS) or ''Lab-on-a-chip'' in combination with electrochemical (stripping-voltammetric) sensors. The resulting microfluidics/electrochemical sensor system would allow testing for toxic metals to be performed more rapidly, inexpensively, and reliably in a field setting. Progress Summary/Accomplishments: This report summarizes the ASU activity over the second year of the project. In accordance to our original objectives our studies have focused on various fundamental and practical aspects of sensing and microchip devices for monitoring metal contaminants. As described in this section, we have made a substantial progress, and introduced effective routes for improving the on-site detection of toxic metals and for interfacing microchips with the real world.

  3. Field portable low temperature porous layer open tubular cryoadsorption headspace sampling and analysis part II: Applications.

    PubMed

    Harries, Megan; Bukovsky-Reyes, Santiago; Bruno, Thomas J

    2016-01-15

    This paper details the sampling methods used with the field portable porous layer open tubular cryoadsorption (PLOT-cryo) approach, described in Part I of this two-part series, applied to several analytes of interest. We conducted tests with coumarin and 2,4,6-trinitrotoluene (two solutes that were used in initial development of PLOT-cryo technology), naphthalene, aviation turbine kerosene, and diesel fuel, on a variety of matrices and test beds. We demonstrated that these analytes can be easily detected and reliably identified using the portable unit for analyte collection. By leveraging efficiency-boosting temperature control and the high flow rate multiple capillary wafer, very short collection times (as low as 3s) yielded accurate detection. For diesel fuel spiked on glass beads, we determined a method detection limit below 1 ppm. We observed greater variability among separate samples analyzed with the portable unit than previously documented in work using the laboratory-based PLOT-cryo technology. We identify three likely sources that may help explain the additional variation: the use of a compressed air source to generate suction, matrix geometry, and variability in the local vapor concentration around the sampling probe as solute depletion occurs both locally around the probe and in the test bed as a whole. This field-portable adaptation of the PLOT-cryo approach has numerous and diverse potential applications.

  4. Field portable low temperature porous layer open tubular cryoadsorption headspace sampling and analysis part II: Applications.

    PubMed

    Harries, Megan; Bukovsky-Reyes, Santiago; Bruno, Thomas J

    2016-01-15

    This paper details the sampling methods used with the field portable porous layer open tubular cryoadsorption (PLOT-cryo) approach, described in Part I of this two-part series, applied to several analytes of interest. We conducted tests with coumarin and 2,4,6-trinitrotoluene (two solutes that were used in initial development of PLOT-cryo technology), naphthalene, aviation turbine kerosene, and diesel fuel, on a variety of matrices and test beds. We demonstrated that these analytes can be easily detected and reliably identified using the portable unit for analyte collection. By leveraging efficiency-boosting temperature control and the high flow rate multiple capillary wafer, very short collection times (as low as 3s) yielded accurate detection. For diesel fuel spiked on glass beads, we determined a method detection limit below 1 ppm. We observed greater variability among separate samples analyzed with the portable unit than previously documented in work using the laboratory-based PLOT-cryo technology. We identify three likely sources that may help explain the additional variation: the use of a compressed air source to generate suction, matrix geometry, and variability in the local vapor concentration around the sampling probe as solute depletion occurs both locally around the probe and in the test bed as a whole. This field-portable adaptation of the PLOT-cryo approach has numerous and diverse potential applications. PMID:26726934

  5. Technology assessment of field portable instrumentation for use at Rocky Mountain Arsenal. Final report, May 1987-March 1988

    SciTech Connect

    Jenkins, R.A.; Maskarinec, M.P.; Griest, W.H.; Dyer, F.F.; Moody, R.L.

    1988-07-01

    An assessment was made of commercially available field instrumentation for analysis of samples at Rocky Mountain Arsenal. The analytes considered were metals, volatile organics, and semivolatile organics. Colorimetric tests for metals are recommended for screening, with positives being confirmed by microwave digestion followed by portable atomic absorption. A portable mercury monitor is recommended for this analysis. Portable X-ray fluorescence is recommended for higher levels of inorganics. For volatile organics, purge and trap and heated headspace followed by portable gas chromatography are recommended. For semivolatiles in soil, SOXTEC extraction and gas or thin-layer chromatography are recommended. For semivolatiles in water, solvent extraction using a MIXXOR is recommended.

  6. Field-usable portable analyzer for chlorinated organic compounds

    SciTech Connect

    Buttner, W.J.; Penrose, W.R.; Stetter, J.R.

    1995-10-01

    Transducer Research, Inc. (TRI) has been working with the DOE Morgantown Energy Technology Center to develop a new chemical monitor based on a unique sensor which responds selectively to vapors of chlorinated solvents. We are also developing field applications for the monitor in actual DOE cleanup operations. During the initial phase, prototype instruments were built and field tested. Because of the high degree of selectivity that is obtained, no response was observed with common hydrocarbon organic compounds such as BTX (benzene, toluene, xylene) or POLs (petroleum, oil, lubricants), and in fact, no non-halogen-containing chemical has been identified which induces a measurable response. By the end of the Phase I effort, a finished instrument system was developed and test marketed. This instrument, called the RCL MONITOR, was designed to analyze individual samples or monitor an area with automated repetitive analyses. Vapor levels between 0 and 500 ppm can be determined in 90 s with a lower detection limit of 0.2 ppm using the handportable instrument. In addition to the development of the RCL MONITOR, advanced sampler systems are being developed to: (1) extend the dynamic range of the instrument through autodilution of the vapor and (2) allow chemical analyses to be performed on aqueous samples. When interfaced to the samplers, the RCL MONITOR is capable of measuring chlorinated solvent contamination in the vapor phase up to 5000 ppm and in water and other condensed media from 10 to over 10,000 ppb(wt)--without hydrocarbon and other organic interferences.

  7. Field tests of acoustic telemetry for a portable coastal observatory

    USGS Publications Warehouse

    Martini, M.; Butman, B.; Ware, J.; Frye, D.

    2006-01-01

    Long-term field tests of a low-cost acoustic telemetry system were carried out at two sites in Massachusetts Bay. At each site, an acoustic Doppler current profiler mounted on a bottom tripod was fitted with an acoustic modem to transmit data to a surface buoy; electronics mounted on the buoy relayed these data to shore via radio modem. The mooring at one site (24 m water depth) was custom-designed for the telemetry application, with a custom designed small buoy, a flexible electro-mechanical buoy to mooring joint using a molded chain connection to the buoy, quick-release electro-mechanical couplings, and dual hydrophones suspended 7 m above the bottom. The surface buoy at the second site (33 m water depth) was a U.S. Coast Guard (USCG) channel buoy fitted with telemetry electronics and clamps to hold the hydrophones. The telemetry was tested in several configurations for a period of about four years. The custom-designed buoy and mooring provided nearly error-free data transmission through the acoustic link under a variety of oceanographic conditions for 261 days at the 24 m site. The electro mechanical joint, cables and couplings required minimal servicing and were very reliable, lasting 862 days deployed before needing repairs. The acoustic communication results from the USCG buoy were poor, apparently due to the hard cobble bottom, noise from the all-steel buoy, and failure of the hydrophone assembly. Access to the USCG buoy at sea required ideal weather. ??2006 IEEE.

  8. Field-Portable Immunoassay Instruments and Reagents to Measure Chelators and Mobile Forms of Uranium

    SciTech Connect

    Blake, Diane A.

    2001-06-01

    Previous studies from our laboratory have demonstrated the feasibility of immunoassays for identification and quantification of specific metal ions. Our ultimate goal for this project is to (1) isolate and characterize antibodies that recognize the most mobile form of uranium, UO22+; (2) assemble, test, and validate a new field-portable immunosensor based on these antibodies; (3) prepare new monoclonal antibodies to the primary chelators (EDTA and DTPA) found in DOE wastes.

  9. Application of Microchip Electrophoresis for Clinical Tests

    NASA Astrophysics Data System (ADS)

    Yatsushiro, Shouki; Kataoka, Masatoshi

    Microchip electrophoresis has recently attracted much attention in the field of nuclear acid analysis due to its high efficiency, ease of operation, low consumption of samples and reagents, and relatively low costs. In addition, the analysis has expanded to an analytical field like not only the analysis of DNA but also the analysis of RNA, the protein, the sugar chain, and the cellular function, etc. In this report, we showed that high-performance monitoring systems for human blood glucose levels and α-amylase activity in human plasma using microchip electrophoresis.

  10. Photonic Crystal Microchip Laser

    PubMed Central

    Gailevicius, Darius; Koliadenko, Volodymyr; Purlys, Vytautas; Peckus, Martynas; Taranenko, Victor; Staliunas, Kestutis

    2016-01-01

    The microchip lasers, being very compact and efficient sources of coherent light, suffer from one serious drawback: low spatial quality of the beam strongly reducing the brightness of emitted radiation. Attempts to improve the beam quality, such as pump-beam guiding, external feedback, either strongly reduce the emission power, or drastically increase the size and complexity of the lasers. Here it is proposed that specially designed photonic crystal in the cavity of a microchip laser, can significantly improve the beam quality. Experiments show that a microchip laser, due to spatial filtering functionality of intracavity photonic crystal, improves the beam quality factor M2 reducing it by a factor of 2, and increase the brightness of radiation by a factor of 3. This comprises a new kind of laser, the “photonic crystal microchip laser”, a very compact and efficient light source emitting high spatial quality high brightness radiation. PMID:27683066

  11. Photonic Crystal Microchip Laser

    NASA Astrophysics Data System (ADS)

    Gailevicius, Darius; Koliadenko, Volodymyr; Purlys, Vytautas; Peckus, Martynas; Taranenko, Victor; Staliunas, Kestutis

    2016-09-01

    The microchip lasers, being very compact and efficient sources of coherent light, suffer from one serious drawback: low spatial quality of the beam strongly reducing the brightness of emitted radiation. Attempts to improve the beam quality, such as pump-beam guiding, external feedback, either strongly reduce the emission power, or drastically increase the size and complexity of the lasers. Here it is proposed that specially designed photonic crystal in the cavity of a microchip laser, can significantly improve the beam quality. Experiments show that a microchip laser, due to spatial filtering functionality of intracavity photonic crystal, improves the beam quality factor M2 reducing it by a factor of 2, and increase the brightness of radiation by a factor of 3. This comprises a new kind of laser, the “photonic crystal microchip laser”, a very compact and efficient light source emitting high spatial quality high brightness radiation.

  12. Controlled-release microchips.

    PubMed

    Sharma, Sadhana; Nijdam, A Jasper; Sinha, Piyush M; Walczak, Robbie J; Liu, Xuewu; Cheng, Mark M-C; Ferrari, Mauro

    2006-05-01

    Efficient drug delivery remains an important challenge in medicine: continuous release of therapeutic agents over extended time periods in accordance with a predetermined temporal profile; local delivery at a constant rate to the tumour microenvironment to overcome much of the systemic toxicity and to improve antitumour efficacy; improved ease of administration, and increasing patient compliance required are some of the unmet needs of the present drug delivery technology. Microfabrication technology has enabled the development of novel controlled-release microchips with capabilities not present in the current treatment modalities. In this review, the current status and future prospects of different types of controlled-release microchips are summarised and analysed with reference to microneedle-based microchips, as well as providing an in-depth focus on microreservoir-based and nanoporous microchips.

  13. The SeaWiFS Quality Monitor: A Portable Field Calibration Light Source

    NASA Technical Reports Server (NTRS)

    Shaw, Ping-Shine; Johnson, B. Carol; Hooker, Stanford B.; Lynch, Don

    1997-01-01

    A portable and stable source, the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Quality Monitor, has been developed for use as a field instrument. The source can be used with either radiance- or irradiance-measuring sensors to transfer the laboratory calibration to the field so that the stability of the sensors can be monitored during the experiment. Temperature-controlled silicon photodiodes with colored glass filters are used to monitor the stability of the SeaWiFS Quality Monitor.

  14. Recent innovations in protein separation on microchips by electrophoretic methods.

    PubMed

    Peng, Youyuan; Pallandre, Antoine; Tran, N Thuy; Taverna, Myriam

    2008-01-01

    Microchips for analytical purposes have attracted great attention over the last 20 years. In the present review, we focus on the most recent development of microchips for electrophoretic separation of proteins. This review starts with a short recalling about the microchips covering the basic microchip layout for CE and the commercial chips and microchip platforms. A short paragraph is dedicated to the surface treatment of microchips, which is of paramount importance in protein analysis. One section is dedicated to on-line sample pretreatment in microchips and summarizes different strategies to pre-concentrate or to purify proteins from complex matrixes. Most of the common modes used for CE of proteins have already been adapted to the chip format, while multidimensional approaches are still in progress. The different routes to achieve detection in microchip are also presented with a special attention to derivatization or labeling of proteins. Finally, several recent applications are mentioned. They highlight the great potential of electrophoretic separations of proteins in numerous fields such as biological, pharmaceutical or agricultural and food analysis. A bibliography with 151 references is provided covering papers published from 2000 to the early 2007.

  15. Free-solution electrophoretic separations of DNA-drag-tag conjugates on glass microchips with no polymer network and no loss of resolution at increased electric field strength.

    PubMed

    Albrecht, Jennifer Coyne; Kerby, Matthew B; Niedringhaus, Thomas P; Lin, Jennifer S; Wang, Xiaoxiao; Barron, Annelise E

    2011-05-01

    Here, we demonstrate the potential for high-resolution electrophoretic separations of ssDNA-protein conjugates in borosilicate glass microfluidic chips, with no sieving media and excellent repeatability. Using polynucleotides of two different lengths conjugated to moderately cationic protein polymer drag-tags, we measured separation efficiency as a function of applied electric field. In excellent agreement with prior theoretical predictions of Slater et al., resolution is found to remain constant as applied field is increased up to 700 V/cm, the highest field we were able to apply. This remarkable result illustrates the fundamentally different physical limitations of free-solution conjugate electrophoresis (FSCE)-based DNA separations relative to matrix-based DNA electrophoresis. ssDNA separations in "gels" have always shown rapidly declining resolution as the field strength is increased; this is especially true for ssDNA > 400 bases in length. FSCE's ability to decouple DNA peak resolution from applied electric field suggests the future possibility of ultra-rapid FSCE sequencing on chips. We investigated sources of peak broadening for FSCE separations on borosilicate glass microchips, using six different protein polymer drag-tags. For drag-tags with four or more positive charges, electrostatic and adsorptive interactions with poly(N-hydroxyethylacrylamide)-coated microchannel walls led to appreciable band-broadening, while much sharper peaks were seen for bioconjugates with nearly charge-neutral protein drag-tags.

  16. A mobile phone-based retinal camera for portable wide field imaging.

    PubMed

    Maamari, Robi N; Keenan, Jeremy D; Fletcher, Daniel A; Margolis, Todd P

    2014-04-01

    Digital fundus imaging is used extensively in the diagnosis, monitoring and management of many retinal diseases. Access to fundus photography is often limited by patient morbidity, high equipment cost and shortage of trained personnel. Advancements in telemedicine methods and the development of portable fundus cameras have increased the accessibility of retinal imaging, but most of these approaches rely on separate computers for viewing and transmission of fundus images. We describe a novel portable handheld smartphone-based retinal camera capable of capturing high-quality, wide field fundus images. The use of the mobile phone platform creates a fully embedded system capable of acquisition, storage and analysis of fundus images that can be directly transmitted from the phone via the wireless telecommunication system for remote evaluation. PMID:24344230

  17. Portable, battery-operated, fluorescence field microscope for the developing world

    NASA Astrophysics Data System (ADS)

    Miller, Andrew R.; Davis, Gregory; Pierce, Mark; Oden, Z. Maria; Richards-Kortum, Rebecca

    2010-02-01

    In many areas of the world, current methods for diagnosis of infectious diseases such as malaria and tuberculosis involve microscopic evaluation of a patient specimen. Advances in fluorescence microscopy can improve diagnostic sensitivity and reduce time and expertise necessary to interpret diagnostic results. However, modern research-grade microscopes are neither available nor appropriate for use in many settings in the developing world. To address this need, we designed, fabricated, and tested a portable, battery-powered, bright field and fluorescence inverted field microscope, optimized for infrastructural constraints of the developing world. We characterized an initial prototype constructed with rapidprototyping techniques, which utilized low-cost, over-the-counter components such as a battery-powered LED flashlight as the light source. The microscope exhibited suitable spatial resolution (0.8 μm) in fluorescence mode to resolve M. tuberculosis bacilli. In bright field mode, malaria parasites were resolvable at 1000x magnification. The initial prototype cost 480 USD and we estimate that the microscope can be manufactured for 230 USD. While future studies are planned to evaluate ease-of-use and reliability, our current system serves as a proof of concept that combined fluorescence and bright field microscopy is possible in a low-cost and portable system.

  18. New portable photoacoustic and fluorescence photometer for field measurement of photosynthesis

    NASA Astrophysics Data System (ADS)

    Bélanger, Raymond; Paquette, André; N'soukpoé-Kossi, Christophe N.; Leblanc, Roger M.

    1993-05-01

    A new portable photoacoustic and fluorescence photometer has been built. The instrument is especially made for field measurements but can also be used indoors. This new instrument has many advantages. It can measure the photosynthetic O2 evolution and energy storage, and the vitality index in the same sample. The system is very compact, which makes it easy to transport. A small electrical generator satisfies the 110 V power requirement for field applications. All manipulations are computer controlled including the data acquisition and treatment. The photoacoustic signal-to-noise ratio for carbon black is the same under field conditions as in the laboratory (˜2×104) at 130 Hz. Results obtained on declining sugar maple trees in the field are presented. The combination of photoacoustic and fluorescence measurements in one instrument represents a very powerful tool in photosynthesis research.

  19. Portable biochip scanner device

    DOEpatents

    Perov, Alexander; Sharonov, Alexei; Mirzabekov, Andrei D.

    2002-01-01

    A portable biochip scanner device used to detect and acquire fluorescence signal data from biological microchips (biochips) is provided. The portable biochip scanner device employs a laser for emitting an excitation beam. An optical fiber delivers the laser beam to a portable biochip scanner. A lens collimates the laser beam, the collimated laser beam is deflected by a dichroic mirror and focused by an objective lens onto a biochip. The fluorescence light from the biochip is collected and collimated by the objective lens. The fluorescence light is delivered to a photomultiplier tube (PMT) via an emission filter and a focusing lens. The focusing lens focuses the fluorescence light into a pinhole. A signal output of the PMT is processed and displayed.

  20. Assessment of Copper Pollution in Overbank Sediments by In-situ Measurements Using a Field Portable EDXRF Instrument

    NASA Astrophysics Data System (ADS)

    Civici, Nikolla; Tashko, Artan

    2007-04-01

    The application of a field portable EDXRF instrument for the assessment of Mati River overbank sediments pollution is presented. The portable EDXRF spectrometer is based on a Peltier-cooled Si-PIN X-ray detector and a 740 MBq Cd-109 disc radioactive source. The comparison of the laboratory results with the average results of replicate in-situ measurements showed a rather good agreement. This allowed us to assess the pollution level and localize the contaminated `hot spots'.

  1. A portable fluorescence spectroscopy imaging system for automated root phenotyping in soil cores in the field

    PubMed Central

    Wasson, Anton; Bischof, Leanne; Zwart, Alec; Watt, Michelle

    2016-01-01

    Root architecture traits are a target for pre-breeders. Incorporation of root architecture traits into new cultivars requires phenotyping. It is attractive to rapidly and directly phenotype root architecture in the field, avoiding laboratory studies that may not translate to the field. A combination of soil coring with a hydraulic push press and manual core-break counting can directly phenotype root architecture traits of depth and distribution in the field through to grain development, but large teams of people are required and labour costs are high with this method. We developed a portable fluorescence imaging system (BlueBox) to automate root counting in soil cores with image analysis software directly in the field. The lighting system was optimized to produce high-contrast images of roots emerging from soil cores. The correlation of the measurements with the root length density of the soil cores exceeded the correlation achieved by human operator measurements (R 2=0.68 versus 0.57, respectively). A BlueBox-equipped team processed 4.3 cores/hour/person, compared with 3.7 cores/hour/person for the manual method. The portable, automated in-field root architecture phenotyping system was 16% more labour efficient, 19% more accurate, and 12% cheaper than manual conventional coring, and presents an opportunity to directly phenotype root architecture in the field as part of pre-breeding programs. The platform has wide possibilities to capture more information about root health and other root traits in the field. PMID:26826219

  2. Nanoparticle-Based Paper Sensors for Field-Portable Analysis of Antioxidants

    NASA Astrophysics Data System (ADS)

    Sharpe, Erica Marie

    Abstract & Overview: The goal of this thesis was to develop portable nanoparticle-based paper sensors for field analysis, with focus on antioxidant detection. The method introduces a novel concept in the sensing arena that relies on the use of redox active inorganic nanoparticles, primarily cerium oxide, as colorimetric probes to replace commonly used soluble dyes. The sensors have an integrated detection mechanism with all the reagents needed for analysis confined to the sensing platform. Research work in this thesis focuses on the study of the redox and surface chemistry of these particles, their reactivity with target analytes and integration into paper-based platforms. A unique feature of these particles is their ability to replace or stabilize enzymes and extend their operational lifetime providing additional opportunities for improved detection schemes for enzyme-based systems. We demonstrate the above principles for the construction of sensors for detection of analytes such as hydrogen peroxide, glucose, and polyphenolic antioxidants. The advantage of the newly designed system include, in addition to portability and stability, the low production costs, the rapid analysis time, and the ability to provide quantitative information without use of advanced instrumentation. The results of this work opened up new opportunities for designing portable easy-to- use sensors for field analysis. The developed assays are particularly appealing for remote sensing applications where specialized equipment is not available, and also for high throughput analysis of a large number of samples. Our investigation to demonstrate applicability of the system focused primarily on the detection of antioxidants. Therefore, the thesis highlights predominantly this application.

  3. A portable high-field pulsed magnet system for x-ray scattering studies.

    SciTech Connect

    Islam, Z.; Ruff, J.P.C.; Nojiri, H.; Matsuda, Y. H.; Ross, K. A.; Gaulin, B. D.; Qu, Z.; Lang, J. C.

    2009-01-01

    We present a portable pulsed-magnet system for x-ray studies of materials in high magnetic fields (up to 30 T). The apparatus consists of a split-pair of minicoils cooled on a closed-cycle cryostat, which is used for x-ray diffraction studies with applied field normal to the scattering plane. A second independent closed-cycle cryostat is used for cooling the sample to near liquid helium temperatures. Pulsed magnetic fields (- 1 ms in total duration) are generated by discharging a configurable capacitor bank into the magnet coils. Time-resolved scattering data are collected using a combination of a fast single-photon counting detector, a multichannel scaler, and a high-resolution digital storage oscilloscope. The capabilities of this instrument are used to study a geometrically frustrated system revealing strong magnetostrictive effects in the spin-liquid state.

  4. The Development and Field Testing of the Portable Acousto-optic Spectrometer for Astrobiology

    NASA Astrophysics Data System (ADS)

    Chanover, Nancy J.; Uckert, Kyle; Voelz, David; Boston, Penelope

    2014-11-01

    The development of in situ instrumentation for the detection of biomarkers on planetary surfaces is critical for the search for evidence of present or past life in our solar system. In our earlier instrument development efforts we addressed this need through the development of a near-infrared point spectrometer intended for quick-look examinations of samples that could be subsequently analyzed with a laser desorption time-of-flight mass spectrometer. The point spectrometer utilized an acousto-optic tunable filter (AOTF) crystal as the wavelength selecting element. In parallel with the aforementioned development efforts we identified the need for a portable version of the AOTF spectrometer that we could test and demonstrate in a range of field locations on Earth chosen to serve as terrestrial analogs for extreme environments elsewhere in the solar system. Here we describe the development and field testing of the Portable Acousto-optic Spectrometer for Astrobiology (PASA). We demonstrated this instrument in two very different cave environments, a predominantly gypsum and calcite cave in New Mexico and an actively forming cave rich in hydrated sulfates in Tabasco, Mexico. Both of these microbially active environments contain evidence of biologic alteration of minerals, which can be detected using IR spectroscopy. We will describe the instrument operations and present some data acquired with PASA to demonstrate its efficacy as a tool for biomarker detection on planetary surfaces. This work was supported by NASA's EPSCoR program through grant number NNX12AK77A.

  5. Using Field-Metered Data to Quantify Annual Energy Use of Portable Air Conditioners

    SciTech Connect

    Burke, Thomas; Willem, Henry; Ni, Chun Chun; Stratton, Hannah; Chen, Yuting; Ganeshalingam, Mohan; Iyer, Maithili; Price, Sarah; Dunham, Camilla

    2014-12-01

    As many regions of the United States experience rising temperatures, consumers have come to rely increasingly on cooling appliances (including portable air conditioners) to provide a comfortable indoor temperature. Home occupants sometimes use a portable air conditioner (PAC) to maintain a desired indoor temperature in a single room or enclosed space. Although PACs in residential use are few compared to centrally installed and room air conditioning (AC) units, the past few years have witnessed an increase of PACs use throughout the United States. There is, however, little information and few research projects focused on the energy consumption and performance of PACs, particularly studies that collect information from field applications of PACs. The operation and energy consumption of PACs may differ among geographic locations and households, because of variations in cooling load, frequency, duration of use, and other user-selected settings. In addition, the performance of building envelope (thermal mass and air leakage) as well as inter-zonal mixing within the building would substantially influence the ability to control and maintain desirable indoor thermal conditions. Lawrence Berkeley National Laboratory (LBNL) conducted an initial field-metering study aimed at increasing the knowledge and data related to PAC operation and energy consumption in the United States.

  6. Rapid Measurements of Snow Stratigraphy Using A Portable Penetration Field Instrument

    NASA Astrophysics Data System (ADS)

    Foster, Robert; Louge, Michel; Clifford, Kelly; Decker, Rand

    We describe a new field-portable tool for avalanche forecasting and hydrology that can rapidly generate stratigraphic profiles of density, permittivity and temperature through the snow pack. This penetration instrument consists of a wedged capacitance tip mounted at the end of a pole and a mechanical depth gauge. By appropriate place- ment of its reference, guard and sensor conductive surfaces, the instrument sheds hor- izontal electric field lines resolving horizontal snow layers of 2.5mm thickness. The probe was tested under realistically cold conditions at the mountain resort of Alta near Salt Lake City, Utah. There, it recorded the stratigraphy of the real and imaginary parts of the dielectric constant at 3.9kHz and the temperature through a typical winter snow pack. The portable electronics was carried in a small backpack and the depth was recorded using a rotary digital encoder in frictional contact with the pole. The profiles were automatically acquired on a hand-held Personal Digital Assistant. Using independent calibrations, measurements of the real part provided an accurate profile of density later confirmed by the conventional excavation of a detailed snow cover profile. The ratio of the imaginary and real permittivities also revealed the signature of individual snow layers that could be identified in the excavation.

  7. Field portable low temperature porous layer open tubular cryoadsorption headspace sampling and analysis part I: Instrumentation.

    PubMed

    Bruno, Thomas J

    2016-01-15

    Building on the successful application in the laboratory of PLOT-cryoadsorption as a means of collecting vapor (or headspace) samples for chromatographic analysis, in this paper a field portable apparatus is introduced. This device fits inside of a briefcase (aluminum tool carrier), and can be easily transported by vehicle or by air. The portable apparatus functions entirely on compressed air, making it suitable for use in locations lacking electrical power, and for use in flammable and explosive environments. The apparatus consists of four aspects: a field capable PLOT-capillary platform, the supporting equipment platform, the service interface between the PLOT-capillary and the supporting equipment, and the necessary peripherals. Vapor sampling can be done with either a hand piece (containing the PLOT capillary) or with a custom fabricated standoff module. Both the hand piece and the standoff module can be heated and cooled to facilitate vapor collection and subsequent vapor sample removal. The service interface between the support platform and the sampling units makes use of a unique counter current approach that minimizes loss of cooling and heating due to heat transfer with the surroundings (recuperative thermostatting). Several types of PLOT-capillary elements and sampling probes are described in this report. Applications to a variety of samples relevant to forensic and environmental analysis are discussed in a companion paper. PMID:26687166

  8. Biotoxin sensing in food and environment via microchip.

    PubMed

    Zhang, Zhaowei; Yu, Li; Xu, Lin; Hu, Xiaofeng; Li, Peiwu; Zhang, Qi; Ding, Xiaoxia; Feng, Xiaojun

    2014-06-01

    Biotoxin contamination in food and environmental samples has threatened health or life of human and animals. Thus, a rapid lab-independent sensing method for biotoxin determination is urgently required. Microchip sensing system allows a promising rapid and low-cost detection strategy. Herein, the recent development of various microchips, including microfluidic chip and microarray, has been discussed to sense various biotoxins in food and environmental samples (i.e. phytotoxin, animal toxin, marine toxin, and mycotoxin). Microchip can be served as both analyte transportation and sensing platform, via either labeling or labeling-free sensing strategy. Because of its fast sensing time, low sample consumption, ready portability, and high compatibility, it has been extensively employed in biotoxin determination in both academic and industrial circle. With the advances of fabrication strategies and sensing modes, the microchip performance has been dramatically improved, including sensitivity, efficiency, reliability, stability, cost saving, portability. The potential applications can be found wide spread in biotoxin sensing in the near future, while their practical application in real sample need to be addressed.

  9. Moving your laboratories to the field – Advantages and limitations of the use of field portable instruments in environmental sample analysis

    SciTech Connect

    Gałuszka, Agnieszka; Migaszewski, Zdzisław M.; Namieśnik, Jacek

    2015-07-15

    The recent rapid progress in technology of field portable instruments has increased their applications in environmental sample analysis. These instruments offer a possibility of cost-effective, non-destructive, real-time, direct, on-site measurements of a wide range of both inorganic and organic analytes in gaseous, liquid and solid samples. Some of them do not require the use of reagents and do not produce any analytical waste. All these features contribute to the greenness of field portable techniques. Several stationary analytical instruments have their portable versions. The most popular ones include: gas chromatographs with different detectors (mass spectrometer (MS), flame ionization detector, photoionization detector), ultraviolet–visible and near-infrared spectrophotometers, X-ray fluorescence spectrometers, ion mobility spectrometers, electronic noses and electronic tongues. The use of portable instruments in environmental sample analysis gives a possibility of on-site screening and a subsequent selection of samples for routine laboratory analyses. They are also very useful in situations that require an emergency response and for process monitoring applications. However, quantification of results is still problematic in many cases. The other disadvantages include: higher detection limits and lower sensitivity than these obtained in laboratory conditions, a strong influence of environmental factors on the instrument performance and a high possibility of sample contamination in the field. This paper reviews recent applications of field portable instruments in environmental sample analysis and discusses their analytical capabilities. - Highlights: • Field portable instruments are widely used in environmental sample analysis. • Field portable instruments are indispensable for analysis in emergency response. • Miniaturization of field portable instruments reduces resource consumption. • In situ analysis is in agreement with green analytical chemistry

  10. 100-OL-1 Operable Unit Field Portable X-Ray Fluorescence (XRF) Analyzer Pilot Study Plans

    SciTech Connect

    Bunn, Amoret L.; Fritz, Brad G.; Wellman, Dawn M.

    2014-07-15

    A pilot study is being conducted to support the approval of the Remedial Investigation/Feasibility Study (RI/FS) Work Plan to evaluate the 100-OL-1 Operable Unit (OU) pre-Hanford orchard lands. Based on comments received by the U.S. Environmental Protection Agency (EPA) and Washington State Department of Ecology, the pilot study will evaluate the use of field portable X-ray fluorescence (XRF) spectrometry measurements for evaluating lead and arsenic concentrations on the soil surface as an indicator of past use of lead arsenate pesticide residue in the OU. The work will be performed in the field during the summer of 2014, and assist in the planning for the characterization activities in the RI/FS.

  11. Portable Upconversion Nanoparticles-Based Paper Device for Field Testing of Drug Abuse.

    PubMed

    He, Mengyuan; Li, Zhen; Ge, Yiying; Liu, Zhihong

    2016-02-01

    We report the first portable upconversion nanoparticles (UCNPs)-based paper device for road-side field testing of cocaine. Upon the recognition of cocaine by two pieces of rationally designed aptamer fragments, the luminescence of UCNPs immobilized on the paper is quenched by Au nanoparticles (AuNPs), which indicates the cocaine concentration. This device can give quantitative results in a short time with high sensitivity using only a smartphone as the apparatus. Moreover, this device is applicable in human saliva samples, and it also can be used to monitor the cocaine content change in blood samples. The results of this work demonstrate the prospect of developing UCNPs-based paper devices for field testing of drug abuse.

  12. Continuous Monitoring of Nitrate and Sulfate in Aerosols with Microchip Electrophoresis

    NASA Astrophysics Data System (ADS)

    Noblitt, S. D.; Henry, C. S.; Collett, J. L.; Hering, S. V.

    2007-12-01

    Routine monitoring of aerosol composition is important since aerosols can negatively affect both the environment and health. Water-soluble inorganic ions are commonly monitored using the particle-into-liquid-sampler coupled to ion chromatography (PILS-IC). However, a less-expensive, faster, and more portable analysis system is desirable. Here, we present the coupling of microchip capillary electrophoresis (MCE) to a water-based condensation particle counter (WCPC) for rapid and continuous monitoring of chloride, nitrate, and sulfate in atmospheric aerosols. To achieve a working system, several obstacles were overcome. A working interface between the electrophoresis microchip and the WCPC sampler was developed. This interface was designed to remove insoluble particles from the analysis stream and to prevent the sampling-induced pressure gradient from altering flow in the microfluidic device. The electrophoresis separation chemistry was optimized for the small chip size, to be free from potential interfering compounds, and to operate continuously for several hours. In-field performance of the integrated system was tested with ambient aerosols. Anion analyses can be performed in less than two minutes with aerosol detection limits similar to the PILS-IC, but with greater portability and reduced cost. Coupling microfluidic devices to aerosol sampling technology proves successful for inorganic anion analysis and shows potential for faster and more sensitive measurements as well as monitoring of other water- soluble aerosol components such as organic acids, cations, and carbohydrates. The reduced cost and size relative to current technology indicate that greater deployment of monitoring stations or the advent of portable analyzers may be feasible.

  13. Fast high-throughput screening of angiotensin-converting enzyme insertion/deletion polymorphism by variable programmed electric field strength-based microchip electrophoresis.

    PubMed

    Sun, Yucheng; Kim, Su-Kang; Zhang, Peng; Woo, Nain; Kang, Seong Ho

    2016-08-15

    An insertion (I)/deletion (D) polymorphism in angiotensin-converting enzyme (ACE) has been associated with susceptibility to various diseases in numerous studies. Traditionally, slab gel electrophoresis (SGE) after polymerase chain reaction (PCR) has been used to genotype this ACE I/D polymorphism. In this study, single- and multi-channel microchip electrophoresis (ME) methods based on variable programmed electric field strength (PEFS) (i.e., low constant, high constant, (+)/(-) staircase, and random electric field strengths) were developed for fast high-throughput screening of this specific polymorphism. The optimum PEFS conditions were set as 470V/cm for 0-9s, 129V/cm for 9-13s, 470V/cm for 13-13.9s, 294V/cm for 13.9-16s, and 470V/cm for 16-20s for single-channel ME, and 615V/cm for 0-22.5s, 231V/cm for 22.5-28.5s, and 615V/cm for 28.5-40s for multi-channel ME, respectively. In the multi-channel PEFS-ME, target ACE I/D polymorphism DNA fragments (D=190bp and I=490bp) were identified within 25s without loss of resolving power, which was ∼300 times faster than conventional SGE. In addition, PCR products of the ACE gene from human blood samples were detected after only 10 cycles by multi-channel PEFS-ME, but not by SGE. This parallel detection multichannel-based PEFS-ME method offers a powerful tool for fast high-throughput ACE I/D polymorphism screening with high sensitivity. PMID:27322633

  14. Fast high-throughput screening of angiotensin-converting enzyme insertion/deletion polymorphism by variable programmed electric field strength-based microchip electrophoresis.

    PubMed

    Sun, Yucheng; Kim, Su-Kang; Zhang, Peng; Woo, Nain; Kang, Seong Ho

    2016-08-15

    An insertion (I)/deletion (D) polymorphism in angiotensin-converting enzyme (ACE) has been associated with susceptibility to various diseases in numerous studies. Traditionally, slab gel electrophoresis (SGE) after polymerase chain reaction (PCR) has been used to genotype this ACE I/D polymorphism. In this study, single- and multi-channel microchip electrophoresis (ME) methods based on variable programmed electric field strength (PEFS) (i.e., low constant, high constant, (+)/(-) staircase, and random electric field strengths) were developed for fast high-throughput screening of this specific polymorphism. The optimum PEFS conditions were set as 470V/cm for 0-9s, 129V/cm for 9-13s, 470V/cm for 13-13.9s, 294V/cm for 13.9-16s, and 470V/cm for 16-20s for single-channel ME, and 615V/cm for 0-22.5s, 231V/cm for 22.5-28.5s, and 615V/cm for 28.5-40s for multi-channel ME, respectively. In the multi-channel PEFS-ME, target ACE I/D polymorphism DNA fragments (D=190bp and I=490bp) were identified within 25s without loss of resolving power, which was ∼300 times faster than conventional SGE. In addition, PCR products of the ACE gene from human blood samples were detected after only 10 cycles by multi-channel PEFS-ME, but not by SGE. This parallel detection multichannel-based PEFS-ME method offers a powerful tool for fast high-throughput ACE I/D polymorphism screening with high sensitivity.

  15. Portable thin layer chromatography for field detection of explosives and propellants

    NASA Astrophysics Data System (ADS)

    Satcher, Joe H.; Maienschein, Jon L.; Pagoria, Philip F.; Racoveanu, Ana; Carman, M. Leslie; Whipple, Richard E.; Reynolds, John G.

    2012-06-01

    A field deployable detection kit for explosives and propellants using thin layer chromatography (TLC) has been developed at Lawrence Livermore National Laboratory (LLNL). The chemistry of the kit has been modified to allow for field detection of propellants (through propellant stabilizers), military explosives, peroxide explosives, nitrates and inorganic oxidizer precursors. For many of these target analytes, the detection limit is in the μg to pg range. A new miniaturized, bench prototype, field portable TLC (Micro TLC) kit has also been developed for the detection and identification of common military explosives. It has been demonstrated in a laboratory environment and is ready for field-testing. The kit is comprised of a low cost set of commercially available components specifically assembled for rapid identification needed in the field and identifies the common military explosives: HMX, RDX, Tetryl, Explosive D or picric acid, and TNT all on one plate. Additional modifications of the Micro TLC system have been made with fluorescent organosilicon co-polymer coatings to detect a large suite of explosives.

  16. A semi-automated, field-portable microscopy platform for clinical diagnostic applications

    NASA Astrophysics Data System (ADS)

    Jagannadh, Veerendra Kalyan; Srinivasan, Rajesh; Gorthi, Sai Siva

    2015-08-01

    Clinical microscopy is a versatile diagnostic platform used for diagnosis of a multitude of diseases. In the recent past, many microfluidics based point-of-care diagnostic devices have been developed, which serve as alternatives to microscopy. However, these point-of-care devices are not as multi-functional and versatile as clinical microscopy. With the use of custom designed optics and microfluidics, we have developed a versatile microscopy-based cellular diagnostic platform, which can be used at the point of care. The microscopy platform presented here is capable of detecting infections of very low parasitemia level (in a very small quantity of sample), without the use of any additional computational hardware. Such a cost-effective and portable diagnostic device, would greatly impact the quality of health care available to people living in rural locations of the world. Apart from clinical diagnostics, it's applicability to field research in environmental microbiology has also been outlined.

  17. Metal oxide based multisensor array and portable database for field analysis of antioxidants

    PubMed Central

    Sharpe, Erica; Bradley, Ryan; Frasco, Thalia; Jayathilaka, Dilhani; Marsh, Amanda; Andreescu, Silvana

    2014-01-01

    We report a novel chemical sensing array based on metal oxide nanoparticles as a portable and inexpensive paper-based colorimetric method for polyphenol detection and field characterization of antioxidant containing samples. Multiple metal oxide nanoparticles with various polyphenol binding properties were used as active sensing materials to develop the sensor array and establish a database of polyphenol standards that include epigallocatechin gallate, gallic acid, resveratrol, and Trolox among others. Unique charge-transfer complexes are formed between each polyphenol and each metal oxide on the surface of individual sensors in the array, creating distinct optically detectable signals which have been quantified and logged into a reference database for polyphenol identification. The field-portable Pantone/X-Rite© CapSure® color reader was used to create this database and to facilitate rapid colorimetric analysis. The use of multiple metal-oxide sensors allows for cross-validation of results and increases accuracy of analysis. The database has enabled successful identification and quantification of antioxidant constituents within real botanical extractions including green tea. Formation of charge-transfer complexes is also correlated with antioxidant activity exhibiting electron transfer capabilities of each polyphenol. The antioxidant activity of each sample was calculated and validated against the oxygen radical absorbance capacity (ORAC) assay showing good comparability. The results indicate that this method can be successfully used for a more comprehensive analysis of antioxidant containing samples as compared to conventional methods. This technology can greatly simplify investigations into plant phenolics and make possible the on-site determination of antioxidant composition and activity in remote locations. PMID:24610993

  18. Metal oxide based multisensor array and portable database for field analysis of antioxidants.

    PubMed

    Sharpe, Erica; Bradley, Ryan; Frasco, Thalia; Jayathilaka, Dilhani; Marsh, Amanda; Andreescu, Silvana

    2014-03-31

    We report a novel chemical sensing array based on metal oxide nanoparticles as a portable and inexpensive paper-based colorimetric method for polyphenol detection and field characterization of antioxidant containing samples. Multiple metal oxide nanoparticles with various polyphenol binding properties were used as active sensing materials to develop the sensor array and establish a database of polyphenol standards that include epigallocatechin gallate, gallic acid, resveratrol, and Trolox among others. Unique charge-transfer complexes are formed between each polyphenol and each metal oxide on the surface of individual sensors in the array, creating distinct optically detectable signals which have been quantified and logged into a reference database for polyphenol identification. The field-portable Pantone/X-Rite© CapSure® color reader was used to create this database and to facilitate rapid colorimetric analysis. The use of multiple metal-oxide sensors allows for cross-validation of results and increases accuracy of analysis. The database has enabled successful identification and quantification of antioxidant constituents within real botanical extractions including green tea. Formation of charge-transfer complexes is also correlated with antioxidant activity exhibiting electron transfer capabilities of each polyphenol. The antioxidant activity of each sample was calculated and validated against the oxygen radical absorbance capacity (ORAC) assay showing good comparability. The results indicate that this method can be successfully used for a more comprehensive analysis of antioxidant containing samples as compared to conventional methods. This technology can greatly simplify investigations into plant phenolics and make possible the on-site determination of antioxidant composition and activity in remote locations. PMID:24610993

  19. Least Squares Magnetic-Field Optimization for Portable Nuclear Magnetic Resonance Magnet Design

    SciTech Connect

    Paulsen, Jeffrey L; Franck, John; Demas, Vasiliki; Bouchard, Louis-S.

    2008-03-27

    Single-sided and mobile nuclear magnetic resonance (NMR) sensors have the advantages of portability, low cost, and low power consumption compared to conventional high-field NMR and magnetic resonance imaging (MRI) systems. We present fast, flexible, and easy-to-implement target field algorithms for mobile NMR and MRI magnet design. The optimization finds a global optimum ina cost function that minimizes the error in the target magnetic field in the sense of least squares. When the technique is tested on a ring array of permanent-magnet elements, the solution matches the classical dipole Halbach solution. For a single-sided handheld NMR sensor, the algorithm yields a 640 G field homogeneous to 16 100 ppm across a 1.9 cc volume located 1.5 cm above the top of the magnets and homogeneous to 32 200 ppm over a 7.6 cc volume. This regime is adequate for MRI applications. We demonstrate that the homogeneous region can be continuously moved away from the sensor by rotating magnet rod elements, opening the way for NMR sensors with adjustable"sensitive volumes."

  20. Analysis of Anions in Ambient Aerosols by Microchip Capillary Electrophoresis

    SciTech Connect

    Liu, Yan; MacDonald, David A.; Yu, Xiao-Ying; Hering, Susanne V.; Collett, Jeffrey L.; Henry, Charles S.

    2006-10-01

    We describe a microchip capillary electrophoresis method for the analysis of nitrate and sulfate in ambient aerosols. Investigating the chemical composition of ambient aerosol particles is essential for understanding their sources and effects. Significant progress has been made towards developing mass spectrometry-based instrumentation for rapid qualitative analysis of aerosols. Alternative methods for rapid quantification of selected high abundance compounds are needed to augment the capacity for widespread routine analysis. Such methods could provide much higher temporal and spatial resolution than can be achieved currently. Inorganic anions comprise a large percentage of particulate mass with nitrate and sulfate among the most abundant species. While ion chromatography has proven very useful for analyzing extracts of time-integrated ambient aerosol samples collected on filters and for semi-continuous, on-line particle composition measurements, there is a growing need for development of new compact, inexpensive approaches to routine on-line aerosol ion analysis for deployment in spatially dense, atmospheric measurement networks. Microchip capillary electrophoresis provides the necessary speed and portability to address this need. In this report, on-column contact conductivity detection is used with hydrodynamic injection to create a simple microchip instrument for analysis of nitrate and sulfate. On-column contact conductivity detection was achieved using a Pd decoupler placed upstream from the working electrodes. Microchips containing two Au or Pd working electrodes showed a good linear range (5-500 µM) and low limits-of-detection for sulfate and nitrate with Au providing the lowest detection limits (1 µM) for both ions. The completed microchip system was used to analyze ambient aerosol filter samples. Nitrate and sulfate concentrations measured by the microchip matched the concentrations measured by ion chromatography.

  1. Liquid phase chromatography on microchips.

    PubMed

    Kutter, Jörg P

    2012-01-20

    Over the past twenty years, the field of microfluidics has emerged providing one of the main enabling technologies to realize miniaturized chemical analysis systems, often referred to as micro-Total Analysis Systems (uTAS), or, more generally, Lab-on-a-Chip Systems (LOC) [1,2]. While microfluidics was driven forward a lot from the engineering side, especially with respect to ink jet and dispensing technology, the initial push and interest from the analytical chemistry community was through the desire to develop miniaturized sensors, detectors, and, very early on, separation systems. The initial almost explosive development of, in particular, chromatographic separation systems on microchips, has, however, slowed down in recent years. This review takes a closer, critical look at how liquid phase chromatography has been implemented in miniaturized formats over the past several years, what is important to keep in mind when developing or working with separations in a miniaturized format, and what challenges and pitfalls remain.

  2. Design of an ultra-portable field transfer radiometer supporting automated vicarious calibration

    NASA Astrophysics Data System (ADS)

    Anderson, Nikolaus; Thome, Kurtis; Czapla-Myers, Jeffrey; Biggar, Stuart

    2015-09-01

    The University of Arizona Remote Sensing Group (RSG) began outfitting the radiometric calibration test site (RadCaTS) at Railroad Valley Nevada in 2004 for automated vicarious calibration of Earth-observing sensors. RadCaTS was upgraded to use RSG custom 8-band ground viewing radiometers (GVRs) beginning in 2011 and currently four GVRs are deployed providing an average reflectance for the test site. This measurement of ground reflectance is the most critical component of vicarious calibration using the reflectance-based method. In order to ensure the quality of these measurements, RSG has been exploring more efficient and accurate methods of on-site calibration evaluation. This work describes the design of, and initial results from, a small portable transfer radiometer for the purpose of GVR calibration validation on site. Prior to deployment, RSG uses high accuracy laboratory calibration methods in order to provide radiance calibrations with low uncertainties for each GVR. After deployment, a solar radiation based calibration has typically been used. The method is highly dependent on a clear, stable atmosphere, requires at least two people to perform, is time consuming in post processing, and is dependent on several large pieces of equipment. In order to provide more regular and more accurate calibration monitoring, the small portable transfer radiometer is designed for quick, one-person operation and on-site field calibration comparison results. The radiometer is also suited for laboratory calibration use and thus could be used as a transfer radiometer calibration standard for ground viewing radiometers of a RadCalNet site.

  3. Applications of a Compact Portable Raman Spectrometer for the Field Analysis of Pigments in Works of Art

    NASA Astrophysics Data System (ADS)

    Bruni, S.; Guglielmi, V.

    The importance of Raman micro-spectroscopy for the identification of pigments in works of art is well established. In recent times, portable Raman spectrometers have been introduced which allows users to perform field analysis directly where the artefacts are placed (churches, museums, archaeological sites, etc.). The present work reports results obtained by a remarkably compact instrument, in particular, on frescoes and illuminated parchments.

  4. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT - FIELD PORTABLE X-RAY FLUORESCENCE ANALYZER - METOREX, INC. X-MET 920-P AND 940

    EPA Science Inventory

    In April 1995, the U.S. Environmental Protection Agency (EPA) sponsored a demonstration of field portable X-ray fluorescence (FPXRF) analyzers. The primary objectives of this demonstration were (1) to determine how well FPXRF analyzers perform in comparison to standard reference...

  5. Moving your laboratories to the field--Advantages and limitations of the use of field portable instruments in environmental sample analysis.

    PubMed

    Gałuszka, Agnieszka; Migaszewski, Zdzisław M; Namieśnik, Jacek

    2015-07-01

    The recent rapid progress in technology of field portable instruments has increased their applications in environmental sample analysis. These instruments offer a possibility of cost-effective, non-destructive, real-time, direct, on-site measurements of a wide range of both inorganic and organic analytes in gaseous, liquid and solid samples. Some of them do not require the use of reagents and do not produce any analytical waste. All these features contribute to the greenness of field portable techniques. Several stationary analytical instruments have their portable versions. The most popular ones include: gas chromatographs with different detectors (mass spectrometer (MS), flame ionization detector, photoionization detector), ultraviolet-visible and near-infrared spectrophotometers, X-ray fluorescence spectrometers, ion mobility spectrometers, electronic noses and electronic tongues. The use of portable instruments in environmental sample analysis gives a possibility of on-site screening and a subsequent selection of samples for routine laboratory analyses. They are also very useful in situations that require an emergency response and for process monitoring applications. However, quantification of results is still problematic in many cases. The other disadvantages include: higher detection limits and lower sensitivity than these obtained in laboratory conditions, a strong influence of environmental factors on the instrument performance and a high possibility of sample contamination in the field. This paper reviews recent applications of field portable instruments in environmental sample analysis and discusses their analytical capabilities.

  6. Moving your laboratories to the field--Advantages and limitations of the use of field portable instruments in environmental sample analysis.

    PubMed

    Gałuszka, Agnieszka; Migaszewski, Zdzisław M; Namieśnik, Jacek

    2015-07-01

    The recent rapid progress in technology of field portable instruments has increased their applications in environmental sample analysis. These instruments offer a possibility of cost-effective, non-destructive, real-time, direct, on-site measurements of a wide range of both inorganic and organic analytes in gaseous, liquid and solid samples. Some of them do not require the use of reagents and do not produce any analytical waste. All these features contribute to the greenness of field portable techniques. Several stationary analytical instruments have their portable versions. The most popular ones include: gas chromatographs with different detectors (mass spectrometer (MS), flame ionization detector, photoionization detector), ultraviolet-visible and near-infrared spectrophotometers, X-ray fluorescence spectrometers, ion mobility spectrometers, electronic noses and electronic tongues. The use of portable instruments in environmental sample analysis gives a possibility of on-site screening and a subsequent selection of samples for routine laboratory analyses. They are also very useful in situations that require an emergency response and for process monitoring applications. However, quantification of results is still problematic in many cases. The other disadvantages include: higher detection limits and lower sensitivity than these obtained in laboratory conditions, a strong influence of environmental factors on the instrument performance and a high possibility of sample contamination in the field. This paper reviews recent applications of field portable instruments in environmental sample analysis and discusses their analytical capabilities. PMID:26051907

  7. Evaluation of a Portable Automated Serum Chemistry Analyzer for Field Assessment of Harlequin Ducks, Histrionicus histrionicus.

    PubMed

    Stoskopf, Michael K; Mulcahy, Daniel M; Esler, Daniel

    2010-01-01

    A portable analytical chemistry analyzer was used to make field assessments of wild harlequin ducks (Histrionicus histrionicus) in association with telemetry studies of winter survival in Prince William Sound, Alaska. We compared serum chemistry results obtained on-site with results from a traditional laboratory. Particular attention was paid to serum glucose and potassium concentrations as potential indicators of high-risk surgical candidates based on evaluation of the field data. The median differential for glucose values (N = 82) between methods was 0.6 mmol/L (quartiles 0.3 and 0.9 mmol/L) with the median value higher when assayed on site. Analysis of potassium on site returned a median of 2.7 mmol/L (N = 88; quartiles 2.4 and 3.0 mmol/L). Serum potassium values were too low for quantitation by the traditional laboratory. Changes in several serum chemistry values following a three-day storm during the study support the value of on site evaluation of serum potassium to identify presurgical patients with increased anesthetic risk.

  8. Design Considerations for a Portable Raman Probe Spectrometer for Field Forensics

    SciTech Connect

    Kelly, James F.; Blake, Thomas A.; Bernacki, Bruce E.; Johnson, Timothy J.

    2012-01-01

    Raman spectroscopy has been shown to be a viable method for explosives detection. Currently most forensic Raman systems are either large, powerful instruments for laboratory experiments or handheld instruments forin situpoint detection. We have chosen to examine the performance of certain benchtop Raman probe systems with the goal of developing an inexpensive, portable system that could be used to operate in a field forensics laboratory to examine explosives-related residues or samples. To this end, a rugged, low distortion line imaging dispersive Raman spectrograph was configured to work at 830 nm laser excitation and was used to determine whether the composition of thin films of plastic explosives or small (e.g., ≤10 μm) particles of RDX or other explosives or oxidizers can be detected, identified, and quantified in the field. With 300 mW excitation energy, concentrations of RDX and PETN can be detected and reconstructed in the case of thin Semtex smears, but further work is needed to push detection limits of areal dosages to the ~1 μg/cm2level. We describe the performance of several probe/spectrograph combinations and show preliminary data for particle detection, calibration and detection linearity for mixed compounds, and so forth.

  9. Detection of waterborne parasites using field-portable and cost-effective lensfree microscopy†

    PubMed Central

    Mudanyali, Onur; Oztoprak, Cetin; Tseng, Derek; Erlinger, Anthony; Ozcan, Aydogan

    2010-01-01

    Protection of human health and well-being through water quality management is an important goal for both the developed and the developing parts of the world. In the meantime, insufficient disinfection techniques still fail to eliminate pathogenic contaminants in freshwater as well as recreational water resources. Therefore, there is a significant need for screening of water quality to prevent waterborne outbreaks and incidents of water-related diseases. Toward this end, here we investigate the use of a field-portable and cost-effective lensfree holographic microscope to image and detect pathogenic protozoan parasites such as Giardia Lamblia and Cryptosporidium Parvum at low concentration levels. This compact lensless microscope (O. Mudanyali et al., Lab Chip, 2010, 10, 1417–1428), weighing ~46 grams, achieves a numerical aperture of ~0.1–0.2 over an imaging field of view that is more than an order of magnitude larger than a typical 10X objective lens, and therefore may provide an important high-throughput analysis tool for combating waterborne diseases especially in resource limited settings. PMID:20694255

  10. Analysis of munitions constituents in groundwater using a field-portable GC-MS.

    PubMed

    Bednar, A J; Russell, A L; Hayes, C A; Jones, W T; Tackett, P; Splichal, D E; Georgian, T; Parker, L V; Kirgan, R A; MacMillan, D K

    2012-05-01

    The use of munitions constituents (MCs) at military installations can produce soil and groundwater contamination that requires periodic monitoring even after training or manufacturing activities have ceased. Traditional groundwater monitoring methods require large volumes of aqueous samples (e.g., 2-4 L) to be shipped under chain of custody, to fixed laboratories for analysis. The samples must also be packed on ice and shielded from light to minimize degradation that may occur during transport and storage. The laboratory's turn-around time for sample analysis and reporting can be as long as 45 d. This process hinders the reporting of data to customers in a timely manner; yields data that are not necessarily representative of current site conditions owing to the lag time between sample collection and reporting; and incurs significant shipping costs for samples. The current work compares a field portable Gas Chromatograph-Mass Spectrometer (GC-MS) for analysis of MCs on-site with traditional laboratory-based analysis using High Performance Liquid Chromatography with UV absorption detection. The field method provides near real-time (within ~1 h of sampling) concentrations of MCs in groundwater samples. Mass spectrometry provides reliable confirmation of MCs and a means to identify unknown compounds that are potential false positives for methods with UV and other non-selective detectors.

  11. Evaluation of Field Portable X-Ray Fluorescence Performance for the Analysis of Ni in Soil.

    PubMed

    Du, Guo-dong; Lei, Mei; Zhou, Guang-dong; Chen, Tong-bin; Qiu, Rong-liang

    2015-03-01

    As a rapid, in-situ analysis method, Field portable X-ray fluorescence spectrometry (FP-XRF) can be widely applied in soil heavy metals analysis field. Whereas, some factors may affect FP-XRF performance and restrict the application. Studies have proved that FP-XRF has poorer performance when the concentration of target element is low, and soil moisture and particle size will affect FP-XRF performance. But few studies have been conducted in depth. This study took an example of Ni, demonstrated the relationship between Ni concentration and FP-XRF performance on accuracy and precision, and gave a critical value. Effects of soil moisture and particle size on accuracy and precision also had been compared. Results show that, FP-XRF performance is related to Ni concentration and the critical value is 400 mg x kg(-1). Relative standard deviation (RSD) and relative uncertainty decrease while the Ni concentration is below 400 mg x kg(-1), hence FP-XRF performance improves with increasing Ni concentration in this range; RSD and relative uncertainty change little while the Ni concentration is above 400 mg x kg(-1), hence FP-XRF performance does not have correlation with Ni concentration any more. For in-situ analysis, the relative uncertainty contributed by soil moisture is 3.77%, and the relative certainty contributed by particle size is 0.56%. Effect of soil moisture is evidently more serious than particle size both on accuracy and precision.

  12. Portable low-coherence interferometry for quantitatively imaging fast dynamics with extended field of view

    NASA Astrophysics Data System (ADS)

    Shaked, Natan T.; Girshovitz, Pinhas; Frenklach, Irena

    2014-06-01

    We present our recent advances in the development of compact, highly portable and inexpensive wide-field interferometric modules. By a smart design of the interferometric system, including the usage of low-coherence illumination sources and common-path off-axis geometry of the interferometers, spatial and temporal noise levels of the resulting quantitative thickness profile can be sub-nanometric, while processing the phase profile in real time. In addition, due to novel experimentally-implemented multiplexing methods, we can capture low-coherence off-axis interferograms with significantly extended field of view and in faster acquisition rates. Using these techniques, we quantitatively imaged rapid dynamics of live biological cells including sperm cells and unicellular microorganisms. Then, we demonstrated dynamic profiling during lithography processes of microscopic elements, with thicknesses that may vary from several nanometers to hundreds of microns. Finally, we present new algorithms for fast reconstruction (including digital phase unwrapping) of off-axis interferograms, which allow real-time processing in more than video rate on regular single-core computers.

  13. Miniaturized Explosive Preconcentrator for Use in a Man-Portable Field Detection System

    SciTech Connect

    Hannum, David W.; Linker, Kevin L.; Parmeter, John E.; Rhykerd, Charles L.; Varley, Nathan R.

    1999-08-02

    We discuss the design and testing of a miniaturized explosives preconcentrator that can be used to enhance the capabilities of man-portable field detection systems, such as those based on ion mobility spectrometry (IMS). The preconcentrator is a smaller version of a similar device that was developed recently at Sandia National Laboratories for use in a trace detection portal that screens personnel for explosives. Like its predecessor, this preconcentrator is basically a filtering device that allows a small amount of explosive residue in a large incoming airflow to be concentrated into a much smaller air volume via adsorption and resorption, prior to delivery into a chemical detector. We discuss laboratory testing of this preconcentrator interfaced to a commercially available IMS-based detection system, with emphasis on the explosives 2,4,6-trinitrotoluene (TNT) and cyclotrimethylenetrinitramine (RDX). The issues investigated include optimization of the preconcentrator volume and inlet airflow, the use of different types of adsorbing surfaces within the preconcentrator, Wd preconcentrator efficiency and concentration factor. We discuss potential field applications of the preconcentrator, as well as avenues for further investigations and improvements.

  14. Preferred sound levels of portable music players and listening habits among adults: a field study.

    PubMed

    Kähäri, Kim R; Aslund, T; Olsson, J

    2011-01-01

    The main purpose of this descriptive field study was to explore music listening habits and preferred listening levels with portable music players (PMPs). We were also interested in seeing whether any exposure differences could be observed between the sexes. Data were collected during 12 hours at Stockholm Central Station, where people passing by were invited to measure their preferred PMP listening level by using a KEMAR manikin. People were also asked to answer a questionnaire about their listening habits. In all, 60 persons (41 men and 19 women) took part in the questionnaire study and 61 preferred PMP levels to be measured. Forty-one of these sound level measurements were valid to be reported after consideration was taken to acceptable measuring conditions. The women (31 years) and the men (33 years) started to use PMPs on a regular basis in their early 20s. Ear canal headphones/ear buds were the preferred headphone types. Fifty-seven percent of the whole study population used their PMP on a daily basis. The measured LAeq60 sec levels corrected for free field ranged between 73 and 102 dB, with a mean value of 83 dB. Sound levels for different types of headphones are also presented. The results of this study indicate that there are two groups of listeners: people who listen less frequently and at lower, safer sound levels, and people with excessive listening habits that may indeed damage their hearing sensory organ in time.

  15. Microchip-based forensic short tandem repeat genotyping.

    PubMed

    Kim, Yong Tae; Heo, Hyun Young; Oh, Shin Hye; Lee, Seung Hwan; Kim, Do Hyun; Seo, Tae Seok

    2015-08-01

    Micro total analysis system (μTAS) or lab-on-a-chip (LOC) technology has advanced over decades, and the high performance for chemical and biological analysis has been well demonstrated with advantages of low sample consumption, rapid analysis time, high-throughput screening, and portability. In particular, μTAS or LOC based genetic applications have been extensively explored, and the short tandem repeat (STR) typing on a chip has garnered attention in the forensic community due to its special use for human identification in the field of mass disaster and missing person investigation, paternity testing, and perpetrator identification. The STR typing process consists of sample collection, DNA extraction, DNA quantitation, STR loci amplification, capillary electrophoretic separation, and STR profiling. Recent progress of microtechnology shows its ability to substitute the conventional analytical tools, and furthermore demonstrates total integration of the whole STR processes on a single wafer for on-site STR typing. In this review article, we highlighted some representative results for fluorescence labeling techniques, microchip-based DNA purification, on-chip polymerase chain reaction (PCR), a capillary electrophoretic microdevice, and a fully integrated microdevice for STR typing. PMID:25963560

  16. Microchip-based forensic short tandem repeat genotyping.

    PubMed

    Kim, Yong Tae; Heo, Hyun Young; Oh, Shin Hye; Lee, Seung Hwan; Kim, Do Hyun; Seo, Tae Seok

    2015-08-01

    Micro total analysis system (μTAS) or lab-on-a-chip (LOC) technology has advanced over decades, and the high performance for chemical and biological analysis has been well demonstrated with advantages of low sample consumption, rapid analysis time, high-throughput screening, and portability. In particular, μTAS or LOC based genetic applications have been extensively explored, and the short tandem repeat (STR) typing on a chip has garnered attention in the forensic community due to its special use for human identification in the field of mass disaster and missing person investigation, paternity testing, and perpetrator identification. The STR typing process consists of sample collection, DNA extraction, DNA quantitation, STR loci amplification, capillary electrophoretic separation, and STR profiling. Recent progress of microtechnology shows its ability to substitute the conventional analytical tools, and furthermore demonstrates total integration of the whole STR processes on a single wafer for on-site STR typing. In this review article, we highlighted some representative results for fluorescence labeling techniques, microchip-based DNA purification, on-chip polymerase chain reaction (PCR), a capillary electrophoretic microdevice, and a fully integrated microdevice for STR typing.

  17. Open channel electrochromatography on a microchip

    SciTech Connect

    Jacobson, S.C.; Hergenroeder, R.; Koutny, L.B.; Ramsey, J.M. )

    1994-07-15

    A glass microchip having a channel with a cross section of 5.6 [mu]m high and 66 [mu]m wide was fabricated using standard photolithographic and etching techniques. The surface of the channel was chemically modified with octadecylsilane to function as the stationary phase for open channel chromatography. Electroosmotic flow was used to [open quotes]load[close quotes] the sample into the microchip and to [open quotes]pump[close quotes] the mobile phase during the experiments. For electric field strengths in the separation column from 27 to 163 V/cm, the linear velocity for the electroosmotic flow ranged from 0.13 to 0.78 mm/s. Detection was performed using direct fluorescence for separation monitoring and indirect fluorescence for void time measurements. Plate heights as low as 4.1 and 5.0 [mu]m were generated for unretained and retained components, respectively. 28 refs., 6 figs., 2 tabs.

  18. Quantitative assessment of historical coastal landfill contamination using in-situ field portable XRF (FPXRF)

    NASA Astrophysics Data System (ADS)

    O'Shea, Francis; Spencer, Kate; Brasington, James

    2014-05-01

    Historically, waste was deposited on low value, easily accessible coastal land (e.g. marsh land). Within England and Wales alone, there are over 5000 historical landfills situated within coastal areas at risk of flooding at a 1 in 100 year return period (Environment Agency, 2012). Historical sites were constructed prior to relevant legislation, and have no basal or side wall engineering, and the waste constituents are mostly unknown. In theory, contaminant concentrations should be reduced through natural attenuation as the leachate plume migrates through surrounding fine-grained inter-tidal sediments before reaching receptor waters. However, erosion resulting from rising sea level and increased storm intensity may re-distribute these sediments and release associated contaminants into the estuarine and coastal environment. The diffuse discharge from these sites has not been quantified and this presents a problem for those landfill managers who are required to complete EIAs. An earlier detailed field campaign at Newlands landfill site, on the Thames Estuary, UK identified a sub-surface (~2m depth) contaminant plume extending c. 20 m from the landfill boundary into surrounding fine-grained saltmarsh sediments. These saltmarsh sediments are risk of being eroded releasing their contaminant load to the Thames Estuary. The aims of this work were to; 1) assess whether this plume is representative of other historical landfills with similar characteristics and 2) to develop a rapid screening methodology using field portable XRF that could be used to identify potential risk of other coastal landfill sites. GIS was used to select landfill sites of similar age, hydrological regime and sedimentary setting in the UK, for comparison. Collection of sediment samples and analysis by ICP OES is expensive and time-consuming, therefore cores were extracted and analysed with a Niton Goldd XRF in-situ. Contaminant data were available immediately and the sampling strategy could be adapted

  19. Possibility of Microchip Electrophoresis for Biological Application

    NASA Astrophysics Data System (ADS)

    Kataoka, Masatoshi; Kido, Jun-Ichi; Shinohara, Yasuo

    Microchip electrophoresis has recently attracted much attention in the field of nuclear acid analysis due to its high efficiency, ease of operation, low consumption of samples and reagents, and relatively low costs. Nucleic acid fragments are separated by capillary electrophoresis in a chip with microfabricated channels, with automated detection as well as on-line data evaluation. Microfabricated devices are forecast to be fundamental to the postgenome era, especially in the field of genetics and medicine. However, although there are many reports of the use of these instruments to evaluate standard DNA, DNA ladders, PCR products, and commercially available plasmid digests, little information is available their use with biological material. In this report, we showed the accuracy of sizing and quantification of endonuclease-digested plasmid DNA. We also showed the feasibility of on-microchip endonuclease treatment of plasmid DNA and sequential analysis as an additional application for DNA analysis. Furthermore, to evaluate the possibility of microchip electrophoresis for biological application, the results of the examination of blood sugar in human plasma and mitochondrial membrane potential were shown.

  20. Using Field-Metered Data to Quantify Annual Energy Use of Portable Air Conditioners

    SciTech Connect

    Burke, Thomas; Willem, Henry; Ni, Chun Chun; Stratton, Hannah; Chen, Yuting; Ganeshalingam, Mohan; Iyer, Maithili; Price, Sarah; Dunham, Camilla

    2014-12-12

    As many regions of the United States experience rising temperatures, consumers have come to rely increasingly on cooling appliances (including portable air conditioners) to provide a comfortable indoor temperature. Home occupants sometimes use a portable air conditioner (PAC) to maintain a desired indoor temperature in a single room or enclosed space. Although PACs in residential use are few compared to centrally installed and room air conditioning (AC) units, the past few years have witnessed an increase of PACs use throughout the United States. There is, however, little information and few research projects focused on the energy consumption and performance of PACs, particularly studies that collect information from field applications of PACs. The operation and energy consumption of PACs may differ among geographic locations and households, because of variations in cooling load, frequency, duration of use, and other user-selected settings. In addition, the performance of building envelope (thermal mass and air leakage) as well as inter-zonal mixing within the building would substantially influence the ability to control and maintain desirable indoor thermal conditions. Lawrence Berkeley National Laboratory (LBNL) conducted an initial field-metering study aimed at increasing the knowledge and data related to PAC operation and energy consumption in the United States. LBNL performed its field-metering study from mid-April to late October 2014. The study, which monitored 19 sites in the Northeastern United States (4 in upstate New York and 15 near Philadelphia), collected real-time data on PAC energy consumption along with information regarding housing characteristics, consumer behavior, and environmental conditions that were expected to affect PAC performance. Given the limited number of test sites, this study was not intended to be statistically representative of PAC users in the United States but rather to understand the system response to the cooling demand and to

  1. Field portable mobile phone based fluorescence microscopy for detection of Giardia lamblia cysts in water samples

    NASA Astrophysics Data System (ADS)

    Ceylan Koydemir, Hatice; Gorocs, Zoltan; McLeod, Euan; Tseng, Derek; Ozcan, Aydogan

    2015-03-01

    Giardia lamblia is a waterborne parasite that causes an intestinal infection, known as giardiasis, and it is found not only in countries with inadequate sanitation and unsafe water but also streams and lakes of developed countries. Simple, sensitive, and rapid detection of this pathogen is important for monitoring of drinking water. Here we present a cost-effective and field portable mobile-phone based fluorescence microscopy platform designed for automated detection of Giardia lamblia cysts in large volume water samples (i.e., 10 ml) to be used in low-resource field settings. This fluorescence microscope is integrated with a disposable water-sampling cassette, which is based on a flow-through porous polycarbonate membrane and provides a wide surface area for fluorescence imaging and enumeration of the captured Giardia cysts on the membrane. Water sample of interest, containing fluorescently labeled Giardia cysts, is introduced into the absorbent pads that are in contact with the membrane in the cassette by capillary action, which eliminates the need for electrically driven flow for sample processing. Our fluorescence microscope weighs ~170 grams in total and has all the components of a regular microscope, capable of detecting individual fluorescently labeled cysts under light-emitting-diode (LED) based excitation. Including all the sample preparation, labeling and imaging steps, the entire measurement takes less than one hour for a sample volume of 10 ml. This mobile phone based compact and cost-effective fluorescent imaging platform together with its machine learning based cyst counting interface is easy to use and can even work in resource limited and field settings for spatio-temporal monitoring of water quality.

  2. Field analyses of (238)U and (226)Ra in two uranium mill tailings piles from Niger using portable HPGe detector.

    PubMed

    Déjeant, Adrien; Bourva, Ludovic; Sia, Radia; Galoisy, Laurence; Calas, Georges; Phrommavanh, Vannapha; Descostes, Michael

    2014-11-01

    The radioactivities of (238)U and (226)Ra in mill tailings from the U mines of COMINAK and SOMAÏR in Niger were measured and quantified using a portable High-Purity Germanium (HPGe) detector. The (238)U and (226)Ra activities were measured under field conditions on drilling cores with 600s measurements and without any sample preparation. Field results were compared with those obtained by Inductive Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) and emanometry techniques. This comparison indicates that gamma-ray absorption by such geological samples does not cause significant deviations. This work shows the feasibility of using portable HPGe detector in the field as a preliminary method to observe variations of radionuclides concentration with the aim of identifying samples of interest. The HPGe is particularly useful for samples with strong secular disequilibrium such as mill tailings. PMID:25036918

  3. Nanofocus of tenth of joules and a portable plasma focus of few joules for field applications

    SciTech Connect

    Soto, Leopoldo; Pavez, Cristian; Moreno, Jose; Tarifeno, Ariel; Pedreros, Jose; Altamirano, Luis

    2009-01-21

    A repetitive pinch plasma focus that works with stored energy less than 1 J per shot has be developed at the Chilean Nuclear Energy Commission. The main features of this device, repetitive Nanofocus, are 5 nF of capacity, 5 nH of inductance, 5-10 kV charging voltage, 60-250 mJ stored energy, 5-10 kA current peak, per shot. The device has been operated at 20 Hz in hydrogen and deuterium. X-ray radiographs of materials of different thickness were obtained. Neutrons were detected using a system based upon {sup 3}He proportional counter in chare integrated mode. However, the reproducibility of this miniaturized device is low and several technological subjects have to be previously solved in order to produce neutrons for periods greater than minutes. Further studies in the Nanofocus are being carried out. In addition, a device with a stored energy of a few joules is being explored. A preliminary compact, low weight (3 kg), portable PF device (25 cmx5 cmx5 cm) for field applications has been designed. This device was designed to operate with few kilovolts (10 kV or less) with a stored energy of 2 J and a repetition rate of 10 Hz without cooling. A neutron flux of the order of 10{sup 4}-10{sup 5} n/s is expected.

  4. Field-Portable Immunoassay Instruments and Reagents to Measure Chelators and Mobile Forms of Uranium

    SciTech Connect

    Blake, Diane A.

    2006-01-23

    Progress Report Date: 01/23/06 (report delayed due to Hurricane Katrina) Report of results to date: The goals of this 3-year project are to: (1) update and successfully deploy our present immunosensors at DOE sites; (2) devise immunosensor-based assays for Pb(II), Hg(II), chelators, and/or Cr(III) in surface and groundwater; and (3) develop new technologies in antibody engineering that will enhance this immunosensor program. Note: Work on this project was temporarily disrupted when Hurricane Katrina shut down the University on August 29, 2005. While most of the reagents stored in our refrigerators and freezers were destroyed, all of our hybridoma cell lines were saved because they had been stored in liquid nitrogen. We set up new tissue culture reactors with the hybridomas that synthesize the anti-uranium antibodies, and are purifying new monoclonal antibodies from these culture supernatants. Both the in-line and the field-portable sensor were rescued from our labs in New Orleans in early October, and we continued experiments with these sensors in the temporary laboratory we set up in Hammond, LA at Southeastern Louisiana University.

  5. Field assessment of noncontact stream gauging using portable surface velocity radars (SVR)

    NASA Astrophysics Data System (ADS)

    Welber, Matilde; Le Coz, Jérôme; Laronne, Jonathan B.; Zolezzi, Guido; Zamler, Daniel; Dramais, Guillaume; Hauet, Alexandre; Salvaro, Martino

    2016-02-01

    The applicability of a portable, commercially available surface velocity radar (SVR) for noncontact stream gauging was evaluated through a series of field-scale experiments carried out in a variety of sites and deployment conditions. Comparisons with various concurrent techniques showed acceptable agreement with velocity profiles, with larger uncertainties close to the banks. In addition to discharge error sources shared with intrusive velocity-area techniques, SVR discharge estimates are affected by flood-induced changes in the bed profile and by the selection of a depth-averaged to surface velocity ratio, or velocity coefficient (α). Cross-sectional averaged velocity coefficients showed smaller fluctuations and closer agreement with theoretical values than those computed on individual verticals, especially in channels with high relative roughness. Our findings confirm that α = 0.85 is a valid default value, with a preferred site-specific calibration to avoid underestimation of discharge in very smooth channels (relative roughness ˜ 0.001) and overestimation in very rough channels (relative roughness > 0.05). Theoretically derived and site-calibrated values of α also give accurate SVR-based discharge estimates (within 10%) for low and intermediate roughness flows (relative roughness 0.001 to 0.05). Moreover, discharge uncertainty does not exceed 10% even for a limited number of SVR positions along the cross section (particularly advantageous to gauge unsteady flood flows and very large floods), thereby extending the range of validity of rating curves.

  6. Advances in field-portable ion trap GC/MS instrumentation

    NASA Astrophysics Data System (ADS)

    Diken, Eric G.; Arno, Josep; Skvorc, Ed; Manning, David; Andersson, Greger; Judge, Kevin; Fredeen, Ken; Sadowski, Charles; Oliphant, Joseph L.; Lammert, Stephen A.; Jones, Jeffrey L.; Waite, Randall W.; Grant, Chad; Lee, Edgar D.

    2012-06-01

    The rapid and accurate detection and identification of chemical warfare agents and toxic industrial chemicals can be critical to the protection of military and civilian personnel. The use of gas chromatography (GC) - mass spectrometry (MS) can provide both the sensitivity and selectivity required to identify unknown chemicals in complex (i.e. real-world) environments. While most widely used as a laboratory-based technique, recent advances in GC, MS, and sampling technologies have led to the development of a hand-portable GC/MS system that is more practical for field-based analyses. The unique toroidal ion trap mass spectrometer (TMS) used in this instrument has multiple benefits related to size, weight, start-up time, ruggedness, and power consumption. Sample separation is achieved in record time (~ 3 minutes) and with high resolution using a state-of-the-art high-performance low-thermal-mass GC column. In addition to providing a system overview highlighting its most important features, the presentation will focus on the chromatographic and mass spectral performance of the system. Results from exhaustive performance testing of the new instrument will be introduced to validate its unique robustness and ability to identify targeted and unknown chemicals.

  7. Operational field evaluation of the PAC-MAG man-portable magnetometer array

    NASA Astrophysics Data System (ADS)

    Keranen, Joe; Topolosky, Zeke; Schultz, Gregory; Miller, Jonathan

    2013-06-01

    Detection and discrimination of unexploded ordnance (UXO) in areas of prior conflict is of high importance to the international community and the United States government. For humanitarian applications, sensors and processing methods need to be robust, reliable, and easy to train and implement using indigenous UXO removal personnel. This paper describes system characterization, system testing, and a continental United States (CONUS) Operational Field Evaluations (OFE) of the PAC-MAG man-portable UXO detection system. System testing occurred at a government test facility in June, 2010 and December, 2011 and the OFE occurred at the same location in June, 2012. NVESD and White River Technologies personnel were present for all testing and evaluation. The PAC-MAG system is a manportable magnetometer array for the detection and characterization of ferrous UXO. System hardware includes four Cesium vapor magnetometers for detection, a Real-time Kinematic Global Position System (RTK-GPS) for sensor positioning, an electronics module for merging array data and WiFi communications and a tablet computer for transmitting and logging data. An odometer, or "hipchain" encoder, provides position information in GPS-denied areas. System software elements include data logging software and post-processing software for detection and characterization of ferrous anomalies. The output of the post-processing software is a dig list containing locations of potential UXO(s), formatted for import into the system GPS equipment for reacquisition of anomalies. Results from system characterization and the OFE will be described.

  8. Apparatus and method for performing electrodynamic focusing on a microchip

    DOEpatents

    Ramsey, J.M.; Jacobson, S.C.

    1999-01-12

    A microchip device includes a focusing channel, in which an electric field strength established in the focusing channel is controlled relative to an electric field strength established in a material transport channel segment to spatially focus the material traversing the material transport channel segment. 22 figs.

  9. Apparatus and method for performing electrodynamic focusing on a microchip

    DOEpatents

    Ramsey, John Michael; Jacobson, Stephen C.

    1999-01-01

    A microchip device includes a focusing channel, in which an electric field strength established in the focusing channel is controlled relative to an electric field strength established in a material transport channel segment to spatially focus the material traversing the material transport channel segment.

  10. Longevity of radiofrequency identification device microchips in citrus trees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Long-term identification of individual plants in the field is an important part of many types of botanical and horticultural research. In a previous report, we described methods for using implanted radiofrequency (RFID) microchips to tag citrus trees for field research. This report provides an upd...

  11. Analysis of the elemental composition of marine litter by field-portable-XRF.

    PubMed

    Turner, Andrew; Solman, Kevin R

    2016-10-01

    Marine litter represents a pervasive environmental problem that poses direct threats to wildlife and habitats. Indirectly, litter can also act as a vehicle for the exposure and bioaccumulation of chemicals that are associated with manufactured or processed solids. In this study, we describe the use of a Niton field-portable-x-ray fluorescence (FP-XRF) spectrometer to determine the content of 17 elements in beached plastics, foams, ropes and painted items. The instrument was used in a 'plastics' mode configured for complex, low density materials, and employed a thickness correction algorithm to account for varying sample depth. Accuracy was evaluated by analysing two reference polyethylene discs and was better than 15% for all elements that had been artificially impregnated into the polymer. Regarding the litter samples, limits of detection for a 120s counting time varied between the different material categories and among the elements but were generally lowest for plastics and painted items with median concentrations of less than 10μgg(-1) for As, Bi, Br, Cr, Hg, Ni, Pb, Se and Zn. Concentrations returned by the XRF were highly sensitive to the thickness correction applied for certain elements (Ba, Cl, Cr, Cu, Fe, Sb, Ti, Zn) in all matrices tested, indicating that accurate measurement and application of the correct thickness is critical for acquiring reliable results. An independent measure of the elemental content of selected samples by ICP spectrometry following acid digestion returned concentrations that were significantly correlated with those returned by the XRF, and with an overall slope of [XRF]/[ICP]=0.85. Within the FP-XRF operating conditions, Cl, Cr, Fe, Ti and Zn were detected in more than 50% and Hg and Se in less than 1% of the 376 litter samples analysed. Significant from an environmental perspective were concentrations of the hazardous elements, Cd, Br and Pb, that exceeded several thousand μgg(-1) in many cases. PMID:27474307

  12. Analysis of the elemental composition of marine litter by field-portable-XRF.

    PubMed

    Turner, Andrew; Solman, Kevin R

    2016-10-01

    Marine litter represents a pervasive environmental problem that poses direct threats to wildlife and habitats. Indirectly, litter can also act as a vehicle for the exposure and bioaccumulation of chemicals that are associated with manufactured or processed solids. In this study, we describe the use of a Niton field-portable-x-ray fluorescence (FP-XRF) spectrometer to determine the content of 17 elements in beached plastics, foams, ropes and painted items. The instrument was used in a 'plastics' mode configured for complex, low density materials, and employed a thickness correction algorithm to account for varying sample depth. Accuracy was evaluated by analysing two reference polyethylene discs and was better than 15% for all elements that had been artificially impregnated into the polymer. Regarding the litter samples, limits of detection for a 120s counting time varied between the different material categories and among the elements but were generally lowest for plastics and painted items with median concentrations of less than 10μgg(-1) for As, Bi, Br, Cr, Hg, Ni, Pb, Se and Zn. Concentrations returned by the XRF were highly sensitive to the thickness correction applied for certain elements (Ba, Cl, Cr, Cu, Fe, Sb, Ti, Zn) in all matrices tested, indicating that accurate measurement and application of the correct thickness is critical for acquiring reliable results. An independent measure of the elemental content of selected samples by ICP spectrometry following acid digestion returned concentrations that were significantly correlated with those returned by the XRF, and with an overall slope of [XRF]/[ICP]=0.85. Within the FP-XRF operating conditions, Cl, Cr, Fe, Ti and Zn were detected in more than 50% and Hg and Se in less than 1% of the 376 litter samples analysed. Significant from an environmental perspective were concentrations of the hazardous elements, Cd, Br and Pb, that exceeded several thousand μgg(-1) in many cases.

  13. Programmable shunt valves: in vitro assessment of safety of the magnetic field generated by a portable game machine.

    PubMed

    Nakashima, Koji; Nakajo, Takato; Kawamo, Michiari; Kato, Akihito; Ishigaki, Seiichiro; Murakami, Hidetomo; Imaizumi, Yohichi; Izumiyama, Hitoshi

    2011-01-01

    Cerebrospinal fluid (CSF) shunts are frequently used to treat hydrocephalus. The use of a programmable shunt valve allows physicians to easily change the opening pressure. Since patients with adjustable CSF shunt valves may use portable game machines, the permanent magnets in these machines may alter the shunt valve programmed settings or permanently damage the device. This study investigated the risk of unintentional valve adjustment associated with the use of game machines in patients with programmable CSF shunt valves. Four adjustable valves from 4 different manufacturers, Sophysa Polaris model SPV (Polaris valve), Miethke proGAV (proGAV), Codman Hakim programmable valve (CHPV), and Strata II small valve (Strata valve), were evaluated. Magnetic field interactions were determined using the portable game machine, Nintendo DS Lite (DS). The maximum distance between the valve and the DS that affected the valve pressure setting was measured by x-ray cinematography. The Polaris valve and proGAV were immune to unintentional reprogramming by the DS. However, the settings of the CHPV and Strata valves were randomly altered by the DS. Patients with an implanted shunt valve should be made aware of the risks posed by the magnetic fields associated with portable game machines and commonly used home electronics. PMID:21946726

  14. Species-Level Identification of Orthopoxviruses with an Oligonucleotide Microchip

    PubMed Central

    Lapa, Sergey; Mikheev, Maxim; Shchelkunov, Sergei; Mikhailovich, Vladimir; Sobolev, Alexander; Blinov, Vladimir; Babkin, Igor; Guskov, Alexander; Sokunova, Elena; Zasedatelev, Alexander; Sandakhchiev, Lev; Mirzabekov, Andrei

    2002-01-01

    A method for species-specific detection of orthopoxviruses pathogenic for humans and animals is described. The method is based on hybridization of a fluorescently labeled amplified DNA specimen with the oligonucleotide DNA probes immobilized on a microchip (MAGIChip). The probes identify species-specific sites within the crmB gene encoding the viral analogue of tumor necrosis factor receptor, one of the most important determinants of pathogenicity in this genus of viruses. The diagnostic procedure takes 6 h and does not require any sophisticated equipment (a portable fluorescence reader can be used). PMID:11880388

  15. Measurement capability of field portable organic vapor monitoring instruments under different experimental conditions.

    PubMed

    Coffey, Christopher C; Pearce, Terri A; Lawrence, Robert B; Hudnall, Judith B; Slaven, James E; Martin, Stephen B

    2009-01-01

    The performance of field portable direct-reading organic vapor monitors (DROVMs) was evaluated under a variety of experimental conditions. Four of the DROVMs had photoionization detectors (ppbRAE, IAQRAE, MultiRAE, and Century Toxic Vapor Analyzer), one had a flame ionization detector (Century Toxic Vapor Analyzer), and one was a single-beam infrared spectrophotometer (SapphIRe). Four of each DROVM (two Century Toxic Vapor Analyzers and SapphIRes) were tested. The DROVMs were evaluated at three temperatures (4 degrees C, 21 degrees C, and 38 degrees C), three relative humidities (30%, 60%, and 90%), and two hexane concentrations (5 ppm and 100 ppm). These conditions were selected to provide a range within the operational parameters of all the instruments. At least four replicate trials were performed across the 18 experimental conditions (3 temperatures x 3 relative humidities x 2 concentrations). To evaluate performance, the 4-hr time-weighted average readings from the DROVMs in a given trial were compared with the average of two charcoal tube concentrations using pairwise comparison. The pairwise comparison criterion was +/-25% measurement agreement between each individual DROVM and the DROVMs as a group and the average charcoal tube concentration. The ppbRAE group performed the best with 40% of all readings meeting the comparison criterion followed by the SapphIRe group at 39%. Among individual DROVMs, the best performer was a SapphIRe, with 57% of its readings meeting the criterion. The data was further analyzed by temperature, humidity, and concentration. The results indicated the performance of some DROVMs may be affected by temperature, humidity, and/or concentration. The ppbRAE group performed best at 21 degrees C with the percentage of readings meeting the criterion increasing to 63%. At the 5 ppm concentration, 44% of the ppbRAE group readings met the criterion, while at 100 ppm, only 35% did. The results indicate that monitors can be used as survey tools

  16. Measurement capability of field portable organic vapor monitoring instruments under different experimental conditions.

    PubMed

    Coffey, Christopher C; Pearce, Terri A; Lawrence, Robert B; Hudnall, Judith B; Slaven, James E; Martin, Stephen B

    2009-01-01

    The performance of field portable direct-reading organic vapor monitors (DROVMs) was evaluated under a variety of experimental conditions. Four of the DROVMs had photoionization detectors (ppbRAE, IAQRAE, MultiRAE, and Century Toxic Vapor Analyzer), one had a flame ionization detector (Century Toxic Vapor Analyzer), and one was a single-beam infrared spectrophotometer (SapphIRe). Four of each DROVM (two Century Toxic Vapor Analyzers and SapphIRes) were tested. The DROVMs were evaluated at three temperatures (4 degrees C, 21 degrees C, and 38 degrees C), three relative humidities (30%, 60%, and 90%), and two hexane concentrations (5 ppm and 100 ppm). These conditions were selected to provide a range within the operational parameters of all the instruments. At least four replicate trials were performed across the 18 experimental conditions (3 temperatures x 3 relative humidities x 2 concentrations). To evaluate performance, the 4-hr time-weighted average readings from the DROVMs in a given trial were compared with the average of two charcoal tube concentrations using pairwise comparison. The pairwise comparison criterion was +/-25% measurement agreement between each individual DROVM and the DROVMs as a group and the average charcoal tube concentration. The ppbRAE group performed the best with 40% of all readings meeting the comparison criterion followed by the SapphIRe group at 39%. Among individual DROVMs, the best performer was a SapphIRe, with 57% of its readings meeting the criterion. The data was further analyzed by temperature, humidity, and concentration. The results indicated the performance of some DROVMs may be affected by temperature, humidity, and/or concentration. The ppbRAE group performed best at 21 degrees C with the percentage of readings meeting the criterion increasing to 63%. At the 5 ppm concentration, 44% of the ppbRAE group readings met the criterion, while at 100 ppm, only 35% did. The results indicate that monitors can be used as survey tools

  17. Micellar electrokinetic chromatography on microchips.

    PubMed

    Kitagawa, Fumihiko; Otsuka, Koji

    2008-03-01

    This review highlights the methodological and instrumental developments in microchip micellar EKC (MCMEKC) from 1995. The combination of higher separation efficiencies in micellar EKC (MEKC) with high-speed separation in microchip electrophoresis (MCE) should provide high-throughput and high-performance analytical systems. The chip-based separation technique has received considerable attention due to its integration ability without any connector. This advantage allows the development of a multidimensional separation system. Several types of 2-D separation microchips are described in the review. Since complicated channel configurations can easily be fabricated on planar substrates, various sample manipulations can be carried out prior to MCMEKC separations. For example, mixing for on-chip reactions, on-line sample preconcentration, on-chip assay, etc., have been integrated on MEKC microchips. The application of on-line sample preconcentration to MCMEKC can provide not only sensitivity enhancement but also the elucidation of the preconcentration mechanism due to the visualization ability of MCE. The characteristics of these sample manipulations on MEKC microchips are presented in this review. The scope of applications in MCMEKC covers mainly biogenic compounds such as amino acids, peptides, proteins, biogenic amines, DNA, and oestrogens. This review provides a comprehensive table listing the applications in MCMEKC in relation to detection methods.

  18. Field comparison of portable and stationary instruments for outdoor urban air exposure assessments

    NASA Astrophysics Data System (ADS)

    Viana, M.; Rivas, I.; Reche, C.; Fonseca, A. S.; Pérez, N.; Querol, X.; Alastuey, A.; Álvarez-Pedrerol, M.; Sunyer, J.

    2015-12-01

    The performance of three portable monitors (micro-aethalometer AE51, DiscMini, Dusttrak DRX) was assessed for outdoor air exposure assessment in a representative Southern European urban environment. The parameters evaluated were black carbon, particle number concentration, alveolar lung-deposited surface area, mean particle diameter, PM10, PM2.5 and PM1. The performance was tested by comparison with widely used stationary instruments (MAAP, CPC, SMPS, NSAM, GRIMM aerosol spectrometer). Results evidenced a good agreement between most portable and stationary instruments, with R2 values mostly >0.80. Relative differences between portable and stationary instruments were mostly <20%, and <10% between different units of the same instrument. The only exception was found for the Dusttrak DRX measurements, for which occasional concentration jumps in the time series were detected. Our results validate the performance of the black carbon, particle number concentration, particle surface area and mean particle diameter monitors as indicative instruments (tier 2) for outdoor air exposure assessment studies.

  19. Portable raman explosives detection

    SciTech Connect

    Moore, David Steven; Scharff, Robert J

    2008-01-01

    Recent advances in portable Raman instruments have dramatically increased their application to emergency response and forensics, as well as homeland defense. This paper reviews the relevant attributes and disadvantages of portable Raman spectroscopy, both essentially and instrumentally, to the task of explosives detection in the field.

  20. Sensitization of a stray-field NMR to vibrations: a potential for MR elastometry with a portable NMR sensor.

    PubMed

    Mastikhin, Igor; Barnhill, Marie

    2014-11-01

    An NMR signal from a sample in a constant stray field of a portable NMR sensor is sensitized to vibrations. The CPMG sequence is synchronized to vibrations so that the constant gradient becomes an "effective" square-wave gradient, leading to the vibration-induced phase accumulation. The integrating nature of the spot measurement, combined with the phase distribution due to a non-uniform gradient and/or a wave field, leads to a destructive interference, the drop in the signal intensity and changes in the echo train shape. Vibrations with amplitudes as small as 140 nm were reliably detected with the permanent gradient of 12.4 T/m. The signal intensity depends on the phase offset between the vibrations and the pulse sequence. This approach opens the way for performing elastometry and micro-rheology measurements with portable NMR devices beyond the walls of a laboratory. Even without synchronization, if a vibration frequency is comparable to 1/2TE of the CPMG sequence, the signal can be severely affected, making it important for potential industrial applications of stray-field NMR.

  1. A portable high-field pulsed-magnet system for single-crystal x-ray scattering studies

    SciTech Connect

    Islam, Zahirul; Lang, Jonathan C.; Ruff, Jacob P. C.; Ross, Kathryn A.; Gaulin, Bruce D.; Nojiri, Hiroyuki; Matsuda, Yasuhiro H.; Qu Zhe

    2009-11-15

    We present a portable pulsed-magnet system for x-ray studies of materials in high magnetic fields (up to 30 T). The apparatus consists of a split-pair of minicoils cooled on a closed-cycle cryostat, which is used for x-ray diffraction studies with applied field normal to the scattering plane. A second independent closed-cycle cryostat is used for cooling the sample to near liquid helium temperatures. Pulsed magnetic fields ({approx}1 ms in total duration) are generated by discharging a configurable capacitor bank into the magnet coils. Time-resolved scattering data are collected using a combination of a fast single-photon counting detector, a multichannel scaler, and a high-resolution digital storage oscilloscope. The capabilities of this instrument are used to study a geometrically frustrated system revealing strong magnetostrictive effects in the spin-liquid state.

  2. A portable high-field pulsed-magnet system for single-crystal x-ray scattering studies.

    PubMed

    Islam, Zahirul; Ruff, Jacob P C; Nojiri, Hiroyuki; Matsuda, Yasuhiro H; Ross, Kathryn A; Gaulin, Bruce D; Qu, Zhe; Lang, Jonathan C

    2009-11-01

    We present a portable pulsed-magnet system for x-ray studies of materials in high magnetic fields (up to 30 T). The apparatus consists of a split-pair of minicoils cooled on a closed-cycle cryostat, which is used for x-ray diffraction studies with applied field normal to the scattering plane. A second independent closed-cycle cryostat is used for cooling the sample to near liquid helium temperatures. Pulsed magnetic fields (approximately 1 ms in total duration) are generated by discharging a configurable capacitor bank into the magnet coils. Time-resolved scattering data are collected using a combination of a fast single-photon counting detector, a multichannel scaler, and a high-resolution digital storage oscilloscope. The capabilities of this instrument are used to study a geometrically frustrated system revealing strong magnetostrictive effects in the spin-liquid state. PMID:19947737

  3. Field evaluation of a prototype man-portable GC/MS

    SciTech Connect

    Arnold, N.S.; Hall, D.L.; Du, W.H.; Sheya, S.A.; Mihamou, H.; Dworzanski, J.; McClennen, W.H.; Meuzelaar, H.L.C.

    1995-12-31

    In recent years, a man-portable gas chromatography/mass spectrometry (GC/MS) system has been developed based on a Hewlett Packard 5971 MSD and a unique automated vapor sampling (AVS) transfer-line (TL) GC system for direct sampling of ambient chemical vapors. The vacuum system and power supplies were replaced to facilitate operation on 24 Vdc batteries for up to 4 hours after startup on a transportable docking station. The gas chromatography was performed on a short (2 m) capillary column under isothermal conditions in a small oven to minimize power usage. Repetitive samples were taken at 10 to 60 s intervals using an automated vapor sampling inlet. In initial testing, the prototype system has been used for monitoring of gasoline vapors. Ambient levels of 6.0 ppm benzene, 4.1 ppm toluene, 0.22 ppm ethylbenzene, 1.1 ppm m- and p-xylene and 0.25 ppm o-xylene were measured near a busy gas station. The gradient mapping or source tracking capabilities of the backpack mounted system have also been demonstrated in tests with a simulated gasoline leak. This paper will describe recent work to further evaluate the capabilities and limitations of the prototype system. Results will be described in terms of the practical utility of portable GC/MS for identification and quantitation of unknown vapors.

  4. Transverse modes in microchip lasers

    SciTech Connect

    Sanchez, F.; Chardon, A.

    1996-12-01

    Two analytical sets of transverse eigenmodes are proposed for microchip lasers in one-dimensional geometry. Each set is associated with a particular pump profile. The eigenfunctions are expressed as Bessel or modified Bessel functions. {copyright} {ital 1996 Optical Society of America.}

  5. Analytical Chemistry and the Microchip.

    ERIC Educational Resources Information Center

    Lowry, Robert K.

    1986-01-01

    Analytical techniques used at various points in making microchips are described. They include: Fourier transform infrared spectrometry (silicon purity); optical emission spectroscopy (quantitative thin-film composition); X-ray photoelectron spectroscopy (chemical changes in thin films); wet chemistry, instrumental analysis (process chemicals);…

  6. Use of field-portable XRF analyzers for rapid screening of toxic elements in FDA-regulated products.

    PubMed

    Palmer, Peter T; Jacobs, Richard; Baker, Peter E; Ferguson, Kelly; Webber, Siri

    2009-04-01

    Analytical instrumentation continues its amazing evolution, especially in regard to generating ever more sensitive, faster, and reliable measurements. Perhaps the most difficult challenges are making these instruments small enough to use in the field, equipping them with well-designed software that facilitates and simplifies their use by nonexperts while preserving enough of their analytical capabilities to render them useful for a wide variety of applications. Perhaps the most impressive and underappreciated example of instruments that meet these criteria are field-portable X-ray fluorescence (XRF) analyzers. In the past, these analyzers have been routinely used for environmental applications (lead in paint and soil, metal particulates in air samples collected onto filters), geology studies (ore and soil analysis, precious metal identification), and recycling industries (alloy identification). However, their use in the analysis of toxic elements in food, food ingredients, dietary supplements, and medicinal and herbal products, especially within the FDA and regulatory environments, has been surprisingly limited to date. Although XRF will not replace atomic spectrometry techniques such as ICP-MS for sub-parts per million level analyses, it offers a number of significant advantages including minimal sample preparation, high sample throughputs, rapid and definitive identification of many toxic elements, and accurate quantitative results. As should be obvious from many recent news reports on elevated levels of toxic elements in children's lunchboxes, toys, and supplements, field-portable XRF analyzers can fill a very important niche and are becoming increasingly popular for a wide variety of elemental analysis applications. This perspective begins with a brief review of the theory of XRF to highlight the underlying principle, instrumentation, and spectra. It includes a discussion of various analytical figures of merit of XRF to illustrate its strengths and limitations

  7. Fused quartz substrates for microchip electrophoresis

    SciTech Connect

    Jacobson, S.C.; Moore, A.W.; Ramsey, J.M.

    1995-07-01

    A fused quartz microchip is fabricated to perform capillary electrophoresis of metal ions complexed with 8-hydroxyquinoline-5-sulfonic acid (HQS). The channel manifold on the quartz substrate is fabricated using standard photolithographic, etching, and deposition techniques. By incorporating a direct bonding technique during the fabrication of the microchip, the substrate and cover plate can be fused together below the melting temperature for fused quartz. To enhance the resolution for the separation, the electroosmotic flow is minimized by covalently bonding polyacrylamide to the channel walls. A separation length of 16.5 mm and separation field strength of 870 V/cm enable separations to be performed in {<=}15 s. By increasing the concentration of HQS from 5 mM to 20 mM, the separation efficiency improves by approximately 3 times. The low background signal from the fused quartz substrate results in mass detection limits of 85, 61, and 134 amol and concentration detection limits of 46, 57, and 30 ppb for Zn, Cd, and Al, respectively. 30 refs., 6 figs., 2 tabs.

  8. Contactless conductivity detector for microchip capillary electrophoresis

    NASA Technical Reports Server (NTRS)

    Pumera, Martin; Wang, Joseph; Opekar, Frantisek; Jelinek, Ivan; Feldman, Jason; Lowe, Holger; Hardt, Steffen; Svehla, D. (Principal Investigator)

    2002-01-01

    A microfabricated electrophoresis chip with an integrated contactless conductivity detection system is described. The new contactless conductivity microchip detector is based on placing two planar sensing aluminum film electrodes on the outer side of a poly(methyl methacrylate) (PMMA) microchip (without contacting the solution) and measuring the impedance of the solution in the separation channel. The contactless route obviates problems (e.g., fouling, unwanted reactions) associated with the electrode-solution contact, offers isolation of the detection system from high separation fields, does not compromise the separation efficiency, and greatly simplifies the detector fabrication. Relevant experimental variables, such as the frequency and amplitude of the applied ac voltage or the separation voltage, were examined and optimized. The detector performance was illustrated by the separation of potassium, sodium, barium, and lithium cations and the chloride, sulfate, fluoride, acetate, and phosphate anions. The response was linear (over the 20 microM-7 mM range) and reproducible (RSD = 3.4-4.9%; n = 10), with detection limits of 2.8 and 6.4 microM (for potassium and chloride, respectively). The advantages associated with the contactless conductivity detection, along with the low cost of the integrated PMMA chip/detection system, should enhance the power and scope of microfluidic analytical devices.

  9. Final Report on Portable Laser Coating Removal Systems Field Demonstrations and Testing

    NASA Technical Reports Server (NTRS)

    Rothgeb, Matthew J.; McLaughlin, Russell L.

    2008-01-01

    Processes currently used throughout the National Aeronautics and Space Administration (NASA) to remove corrosion and coatings from structures, ground service equipment and small components results in waste streams consisting of toxic chemicals, spent media blast materials, and waste water. When chemicals are used in these processes they are typically high in volatile organic compounds (VOC) and are considered hazardous air pollutants (HAP). When blast media is used, the volume of hazardous waste generated is increased significantly. Many of the coatings historically used within NASA contain toxic metals such as hexavalent chromium, and lead. These materials are highly regulated and restrictions on worker exposure continue to increase. Most recently the EPA reduced the permissible exposure limit (PEL) for hexavalent chromium. The new standard lowers OSHA's PEL for hexavalent chromium from 52 to 5 micrograms of Cr(V1) per cubic meter of air as an 8-hour time-weighted average. Hexavalent chromium is found in the pretreatment and primer coatings used within the Shuttle Program. In response to the need to continue to protect assets within the agency and the growing concern over these new regulations, NASA is researching different ways to continue the required maintenance of both facility and flight equipment in a safe, efficient and environmentally preferable manner. The use of laser energy to remove prepare surfaces for a variety of processes, such as corrosion and coating removal, weld preparation and non destructive evaluation is a relatively new technology that has shown itself to be environmentally preferable and in many cases less labor intensive than currently used removal methods. The development of a Portable Laser Coating Removal System (PLCRS) started as the goal of a Joint Group on Pollution Prevention (JG-PP) project, led by the Air Force, where several types of lasers in several configurations were thoroughly evaluated. Following this project, NASA decided

  10. Portable fuel cell systems for America's army: technology transition to the field

    NASA Astrophysics Data System (ADS)

    Patil, Ashok S.; Dubois, Terry G.; Sifer, Nicholas; Bostic, Elizabeth; Gardner, Kristopher; Quah, Michael; Bolton, Christopher

    The US Army Communications, Electronics Research Development and Engineering Center (CERDEC) envisions three thrust areas for portable fuel cell systems for military applications. These areas include soldier power (<500 W), sensor power (0-100 W), and auxiliary power units or APUs (0.5-10 kW). Soldier and sensor fuel cell systems may be man-portable/backpackable while APUs could be employed as squad battery chargers or as 'Silent Watch' APUs where low signature (acoustic, thermal, etc.) operation is a requirement. The Army's research and development efforts are focusing on methods of either storing or generating hydrogen on the battlefield. Hydrogen storage technology is considered critical to small military and/or commercial fuel cell systems, and is being pursued in a host of commercial and government programs. CERDEC, in a joint effort with the Army Research Office (ARO) and the Defense Advanced Research Projects Agency (DARPA), is developing several promising hydrogen generating technologies. The goal of this program is a safe, reliable hydrogen source that can provide rates up to 100 W with an energy density of greater than 1000 Wh/kg. For larger fuel cell units (>500 W), it is imperative that the fuel cell power units be able to operate on fuels within the military logistics chain [DOD 4140.25-M, DOD Directive 4140.25 (1993)]. CERDEC is currently conducting research on catalysts and microchannel fuel reformers that offer great promise for the reforming of diesel and JP-8 fuels into hydrogen. In addition to research work on PEM fuel cells and enabling technologies, the Army is also conducting research on direct methanol and solid oxide fuel cells, and combined heat and power applications utilizing new high temperature fuel cells.

  11. Observations of the Wind Field in Tornadoes, Funnel Clouds, and Wall Clouds with a Portable Doppler Radar.

    NASA Astrophysics Data System (ADS)

    Bluestein, H. B.; Unruh, W. P.

    1989-12-01

    A severe-storm intercept field program was held in Oklahoma and nearby parts of Texas during the 1987-38 spring seasons. The purpose of the experiment was to use, for the first time, a low-power, portable, continuous-wave (CW), 3-cm Doppler radar to obtain wind spectra in tornadoes from a distance of less than 10 km.We discuss measurements of spectra we recorded in a tornado, a funnel cloud, and two wall clouds. Photographic documentation is also given to aid in the interpretation of our data. Wind speeds as high as 60 m s1 were measured in the tornado. It was found that deploying the portable Doppler radar from a storm-intercept vehicle may increase substantially the number of measurements of wind speeds in tornadoes.The radar has recently been modified so that it has frequency modulation (FM) capability, and hence can obtain wind spectra within range bins. A plan is presented for using the radar to find the source of vorticity in tornadoes.

  12. Development of a field-portable small-size impedance analyzer for structural health monitoring using the electromechanical impedance technique

    NASA Astrophysics Data System (ADS)

    Giurgiutiu, Victor; Xu, Buli

    2004-07-01

    Electromechanical (E/M) impedance method is emerging as an effective and powerful technique for structural health monitoring. The E/M impedance method utilizes as its main apparatus an impedance analyzer that reads the in-situ E/M impedance of piezoelectric wafer active sensors (PWAS) attached to the monitored structure. Laboratory-type impedance analyzers (e.g. HP4194) are bulky, heavy, and expensive. They cannot be easily carried into the field for on-site structural health monitoring. To address this issue, means of to reduce the size of the impedance analyzer making the impedance analyzer more compact and field-portable are explored. In this paper, we present a systematic approach to the development of a field-portable small-size impedance analyzer for structural health monitoring using the electromechanical impedance technique. Our approach consists of several developmental stages. First, we perform a simulation of the E/M Impedance technique and develop the software tools for analyzing the signal in a fast and efficient way while maintaining the desired accuracy. The objective of this signal processing part is to obtain the complex impedance, ZR+iZI)=|Z| angle arg Z, at a number of frequencies in a predetermined range. Several signal processing methods were explored such as: (a) integration method; (b) correlation method; (c) Discrete Fourier transform (DFT) method. Second, we discuss the hardware issues associated with the implementation of this approach. The hardware system architecture consists of several blocks: (a) reference signal generation; (b) voltage and current measurements; and (c) digital signal acquisition and processing. Practical results obtained during proof-of-concept experiments are presented and comparatively examined.

  13. Biological cell controllable patch-clamp microchip

    NASA Astrophysics Data System (ADS)

    Penmetsa, Siva; Nagrajan, Krithika; Gong, Zhongcheng; Mills, David; Que, Long

    2010-12-01

    A patch-clamp (PC) microchip with cell sorting and positioning functions is reported, which can avoid drawbacks of random cell selection or positioning for a PC microchip. The cell sorting and positioning are enabled by air bubble (AB) actuators. AB actuators are pneumatic actuators, in which air pressure is generated by microheaters within sealed microchambers. The sorting, positioning, and capturing of 3T3 cells by this type of microchip have been demonstrated. Using human breast cancer cells MDA-MB-231 as the model, experiments have been demonstrated by this microchip as a label-free technical platform for real-time monitoring of the cell viability.

  14. Radially polarized cylindrical vector beams from a monolithic microchip laser

    NASA Astrophysics Data System (ADS)

    Naidoo, Darryl; Fromager, Michael; Ait-Ameur, Kamel; Forbes, Andrew

    2015-11-01

    Monolithic microchip lasers consist of a thin slice of laser crystal where the cavity mirrors are deposited directly onto the end faces. While this property makes such lasers very compact and robust, it prohibits the use of intracavity laser beam shaping techniques to produce complex light fields. We overcome this limitation and demonstrate the selection of complex light fields in the form of vector-vortex beams directly from a monolithic microchip laser. We employ pump reshaping and a thermal gradient across the crystal surface to control both the intensity and polarization profile of the output mode. In particular, we show laser oscillation on a superposition of Laguerre-Gaussian modes of zero radial and nonzero azimuthal index in both the scalar and vector regimes. Such complex light fields created directly from the source could find applications in fiber injection, materials processing and in simulating quantum processes.

  15. Small field of view, high-resolution, portable γ-camera for axillary sentinel node detection

    NASA Astrophysics Data System (ADS)

    Soluri, A.; Massari, R.; Trotta, C.; Tofani, A.; Di Santo, G.; Di Pietro, B.; Di Paolo, M. L.; Roncacci, A.; Amanti, C.; Scopinaro, F.

    2006-12-01

    Sentinel node (SN) biopsy is an established method for breast cancer staging. Many authors suggested lymphoscintigraphy (LS) in order to indicate the sentinel node; others adopted the vital dye method together with radiocolloids, but only with γ-probe detection during operation without preliminary Anger camera LS. The second method is more simple and fast when compared with LS plus radioguided surgery. The Imaging Probe (IP) is a portable, hand held, high-resolution mini γ-camera studied by our group since 1998. Initial studies on sentinel node biopsy were carried out by us with IP on small series of patients to validate and to demonstrate the effectiveness and usefulness of IP against conventional probes. The aim of the present study is to show that surgeon removes the mammary sentinel node quicker and safer when using IP and conventional γ-probe together than conventional probe only. The results of our study not only show that our device makes quicker and safer SN biopsy, but also that the number of detected nodes is larger with our method than with conventional diagnostic and surgical techniques.

  16. Microchip technology in drug delivery.

    PubMed

    Santini, J T; Richards, A C; Scheidt, R A; Cima, M J; Langer, R S

    2000-09-01

    The realization that the therapeutic efficacy of certain drugs can be affected dramatically by the way in which they are delivered has created immense interest in controlled drug delivery systems. Much previous work in drug delivery focused on achieving sustained drug release rates over time, while a more recent trend is to make devices that allow the release rate to be varied over time. Advances in microfabrication technology have made an entirely new type of drug delivery device possible. Proof-of-principle experiments have shown that silicon microchips have the ability to store and release multiple chemicals on demand. Future integration of active control electronics, such as microprocessors, remote control units, or biosensors, could lead to the development of a 'pharmacy on a chip,' ie 'smart' microchip implants or tablets that release drugs into the body automatically when needed.

  17. Use of a field portable X-Ray fluorescence analyzer to determine the concentration of lead and other metals in soil samples.

    PubMed

    Clark, S; Menrath, W; Chen, M; Roda, S; Succop, P

    1999-01-01

    Field portable methods are often needed in risk characterization, assessment and management to rapidly determine metal concentrations in environmental samples. Examples are for determining: "hot spots" of soil contamination, whether dust wipe lead levels meet housing occupancy standards, and worker respiratory protection levels. For over 30 years portable X-Ray Fluorescence (XRF) analyzers have been available for the in situ, non-destructive, measurement of lead in paint. Recent advances made possible their use for analysis of airborne dust filter samples, soil, and dust wipes. Research at the University of Cincinnati with the NITON 700 Series XRF instrument (40 millicurie Cadmium 109 source, L X-Rays) demonstrated its proficiency on air sample filters (NIOSH Method No. 7702, "Lead by Field Portable XRF; limit of detection 6 microg per sample; working range 17-1,500 microg/m3 air). Research with lead dust wipe samples from housing has also shown promising results. This XRF instrument was used in 1997 in Poland on copper smelter area soil samples with the cooperation of the Wroclaw Medical Academy and the Foundation for the Children from the Copper Basin (Legnica). Geometric mean soil lead concentrations were 200 ppm with the portable XRF, 201 ppm with laboratory-based XRF (Kevex) and 190 ppm using atomic absorption (AA). Correlations of field portable XRF and AA results were excellent for samples sieved to less than 125 micrometers with R-squared values of 0.997, 0.957, and 0.976 for lead, copper and zinc respectively. Similarly, correlations were excellent for soil sieved to less than 250 micrometers, where R-squared values were 0. 924, 0.973, and 0.937 for lead, copper and zinc, respectively. The field portable XRF instrument appears to be useful for the determination of soil pollution by these metals in industrial regions.

  18. Preliminary Results from the Portable Imagery Quality Assessment Test Field (PIQuAT) of Uav Imagery for Imagery Reconnaissance Purposes

    NASA Astrophysics Data System (ADS)

    Dabrowski, R.; Orych, A.; Jenerowicz, A.; Walczykowski, P.

    2015-08-01

    The article presents a set of initial results of a quality assessment study of 2 different types of sensors mounted on an unmanned aerial vehicle, carried out over an especially designed and constructed test field. The PIQuAT (Portable Imagery Quality Assessment Test Field) field had been designed especially for the purposes of determining the quality parameters of UAV sensors, especially in terms of the spatial, spectral and radiometric resolutions and chosen geometric aspects. The sensor used include a multispectral framing camera and a high-resolution RGB sensor. The flights were conducted from a number of altitudes ranging from 10 m to 200 m above the test field. Acquiring data at a number of different altitudes allowed the authors to evaluate the obtained results and check for possible linearity of the calculated quality assessment parameters. The radiometric properties of the sensors were evaluated from images of the grayscale target section of the PIQuAT field. The spectral resolution of the imagery was determined based on a number of test samples with known spectral reflectance curves. These reference spectral reflectance curves were then compared with spectral reflectance coefficients at the wavelengths registered by the miniMCA camera. Before conducting all of these experiments in field conditions, the interior orientation parameters were calculated for the MiniMCA and RGB sensor in laboratory conditions. These parameters include: the actual pixel size on the detector, distortion parameters, calibrated focal length (CFL) and the coordinates of the principal point of autocollimation (miniMCA - for each of the six channels separately.

  19. Final Report on NASA Portable Laser Coating Removal Systems Field Demonstrations and Testing

    NASA Technical Reports Server (NTRS)

    Rothgeb, Matthew J; McLaughlin, Russell L.

    2008-01-01

    Portable Laser Coating Removal System (PLCRS) started as the goal of a Joint Group on Pollution Prevention (JG-PP) project, led by the Air Force, where several types of lasers in several configurations were thoroughly evaluated. Following this project, NASA decided to evaluate the best performers on processes and coatings specific to the agency. Laser systems used during this project were all of a similar design, between 40 and 500 Watts, most of which had integrated vacuum systems in order to collect materials removed from substrate surfaces during operation.

  20. Production of Microchips from Polystyrene Plates

    ERIC Educational Resources Information Center

    Pace, Sarah Lindsey

    2009-01-01

    Currently manufactured microchips are expensive to make, require specialized equipment, and leave a large environmental footprint. To counter this, an alternative procedure that is cheaper and leaves a smaller environmental footprint should be made. The goal of this research project is to develop a process that creates microchips from polystyrene…

  1. Disposable polyester-toner electrophoresis microchips for DNA analysis.

    PubMed

    Duarte, Gabriela R M; Coltro, Wendell K T; Borba, Juliane C; Price, Carol W; Landers, James P; Carrilho, Emanuel

    2012-06-01

    Microchip electrophoresis has become a powerful tool for DNA separation, offering all of the advantages typically associated with miniaturized techniques: high speed, high resolution, ease of automation, and great versatility for both routine and research applications. Various substrate materials have been used to produce microchips for DNA separations, including conventional (glass, silicon, and quartz) and alternative (polymers) platforms. In this study, we perform DNA separation in a simple and low-cost polyester-toner (PeT)-based electrophoresis microchip. PeT devices were fabricated by a direct-printing process using a 600 dpi-resolution laser printer. DNA separations were performed on PeT chip with channels filled with polymer solutions (0.5% m/v hydroxyethylcellulose or hydroxypropylcellulose) at electric fields ranging from 100 to 300 V cm(-1). Separation of DNA fragments between 100 and 1000 bp, with good correlation of the size of DNA fragments and mobility, was achieved in this system. Although the mobility increased with increasing electric field, separations showed the same profile regardless of the electric field. The system provided good separation efficiency (215,000 plates per m for the 500 bp fragment) and the separation was completed in 4 min for 1000 bp fragment ladder. The cost of a given chip is approximately $0.15 and it takes less than 10 minutes to prepare a single device.

  2. Characterisation of a high resolution small field of view portable gamma camera.

    PubMed

    Bugby, S L; Lees, J E; Bhatia, B S; Perkins, A C

    2014-05-01

    A handheld, high-resolution small field of view (SFOV) pinhole gamma camera has been characterised using a new set of protocols adapted from standards previously developed for large field of view (LFOV) systems. Parameters investigated include intrinsic and extrinsic spatial resolution, spatial linearity, uniformity, sensitivity, count rate capability and energy resolution. Camera characteristics are compared to some clinical LFOV gamma cameras and also to other SFOV cameras in development.

  3. A laboratory and field evaluation of a portable immunoassay test for triazine herbicides in environmental water samples

    USGS Publications Warehouse

    Schulze, P.A.; Capel, P.D.; Squillace, P.J.; Helsel, D.R.

    1993-01-01

    The usefulness and sensitivity, of a portable immunoassay test for the semiquantitative field screening of water samples was evaluated by means of laboratory and field studies. Laboratory results indicated that the tests were useful for the determination of atrazine concentrations of 0.1 to 1.5 μg/L. At a concentration of 1 μg/L, the relative standard deviation in the difference between the regression line and the actual result was about 40 percent. The immunoassay was less sensitive and produced similar errors for other triazine herbicides. After standardization, the test results were relatively insensitive to ionic content and variations in pH (range, 4 to 10), mildly sensitive to temperature changes, and quite sensitive to the timing of the final incubation step, variances in timing can be a significant source of error. Almost all of the immunoassays predicted a higher atrazine concentration in water samples when compared to results of gas chromatography. If these tests are used as a semiquantitative screening tool, this tendency for overprediction does not diminish the tests' usefulness. Generally, the tests seem to be a valuable method for screening water samples for triazine herbicides.

  4. Rapid and nondestructive measurement of labile Mn, Cu, Zn, Pb and As in DGT by using field portable-XRF.

    PubMed

    Chen, Zheng; Williams, Paul N; Zhang, Hao

    2013-09-01

    The technique of diffusive gradients in thin films (DGT) is often employed to quantify labile metals in situ; however, it is a challenge to perform the measurements in-field. This study evaluated the capability of field-portable X-ray fluorescence (FP-XRF) to swiftly generate elemental speciation information with DGT. Biologically available metal ions in environmental samples passively preconcentrate in the thin films of DGT devices, providing an ideal and uniform matrix for XRF nondestructive detection. Strong correlation coefficients (r > 0.992 for Mn, Cu, Zn, Pb and As) were obtained for all elements during calibration. The limits of quantitation (LOQ) for the investigated elements of FP-XRF on DGT devices are 2.74 for Mn, 4.89 for Cu, 2.89 for Zn, 2.55 for Pb, and 0.48 for As (unit: μg cm(-2)). When Pb and As co-existed in the solution trials, As did not interfere with Pb detection when using Chelex-DGT. However, there was a significant enhancement of the Pb reading attributed to As when ferrihydrite binding gels were tested, consistent with Fe-oxyhydroxide surfaces absorbing large quantities of As. This study demonstrates the value of the FP-XRF technique to rapidly and nondestructively detect the metals accumulated in DGT devices, providing a new and simple diagnostic tool for on-site environmental monitoring of labile metals/metalloids.

  5. Microchip ELISA coupled with cell phone to detect ovarian cancer HE4 biomarker in urine.

    PubMed

    Wang, ShuQi; Akbas, Ragip; Demirci, Utkan

    2015-01-01

    Ovarian cancer is a leading cause of death from gynecologic cancers in the USA, and early diagnosis can potentially increase 5-year survival rate. Detection of biomarkers derived from hyperplasia of epithelial tissue by enzyme-linked immunosorbent assay (ELISA) proves to be a practical way of early diagnosis of ovarian cancer. However, ELISA is commonly performed in a laboratory setting, and it cannot be used in a clinical setting for on-site consultation. We have shown a microchip ELISA that detects HE4, an ovarian cancer biomarker, from urine using a cell phone integrated with a mobile application for imaging and data analysis. In microchip ELISA, HE4 from urine was first absorbed on the surface; the primary and secondary antibodies were subsequently anchored on the surface via immuno-reaction; and addition of substrate led to color development because of enzymatic labeling. The microchip after color development was imaged using a cell phone, and the color intensity was analyzed by an integrated mobile application. By comparing with an ELISA standard curve, the concentration of HE4 was reported on the cell phone screen. The presented microchip ELISA coupled with a cell phone is portable as opposed to traditional ELISA, and this method can facilitate the detection of ovarian cancer at the point-of-care (POC). PMID:25626535

  6. Microchip ELISA coupled with cell phone to detect ovarian cancer HE4 biomarker in urine.

    PubMed

    Wang, ShuQi; Akbas, Ragip; Demirci, Utkan

    2015-01-01

    Ovarian cancer is a leading cause of death from gynecologic cancers in the USA, and early diagnosis can potentially increase 5-year survival rate. Detection of biomarkers derived from hyperplasia of epithelial tissue by enzyme-linked immunosorbent assay (ELISA) proves to be a practical way of early diagnosis of ovarian cancer. However, ELISA is commonly performed in a laboratory setting, and it cannot be used in a clinical setting for on-site consultation. We have shown a microchip ELISA that detects HE4, an ovarian cancer biomarker, from urine using a cell phone integrated with a mobile application for imaging and data analysis. In microchip ELISA, HE4 from urine was first absorbed on the surface; the primary and secondary antibodies were subsequently anchored on the surface via immuno-reaction; and addition of substrate led to color development because of enzymatic labeling. The microchip after color development was imaged using a cell phone, and the color intensity was analyzed by an integrated mobile application. By comparing with an ELISA standard curve, the concentration of HE4 was reported on the cell phone screen. The presented microchip ELISA coupled with a cell phone is portable as opposed to traditional ELISA, and this method can facilitate the detection of ovarian cancer at the point-of-care (POC).

  7. Development of a microchip Europium nanoparticle immunoassay for sensitive point-of-care HIV detection.

    PubMed

    Liu, Jikun; Du, Bingchen; Zhang, Panhe; Haleyurgirisetty, Mohan; Zhao, Jiangqin; Ragupathy, Viswanath; Lee, Sherwin; DeVoe, Don L; Hewlett, Indira K

    2014-11-15

    Rapid, sensitive and specific diagnostic assays play an indispensable role in determination of HIV infection stages and evaluation of efficacy of antiretroviral therapy. Recently, our laboratory developed a sensitive Europium nanoparticle-based microtiter-plate immunoassay capable of detecting target analytes at subpicogram per milliliter levels without the use of catalytic enzymes and signal amplification processes. Encouraged by its sensitivity and simplicity, we continued to miniaturize this assay to a microchip platform for the purpose of converting the benchtop assay technique to a point-of-care test. It was found that detection capability of the microchip platform could be readily improved using Europium nanoparticle probes. We were able to routinely detect 5 pg/mL (4.6 attomoles) of HIV-1 p24 antigen at a signal-to-blank ratio of 1.5, a sensitivity level reasonably close to that of microtiter-plate Europium nanoparticle assay. Meanwhile, use of the microchip platform effectively reduced sample/reagent consumption 4.5 fold and shortened total assay time 2 fold in comparison with microtiter plate assays. Complex matrix substance in plasma negatively affected the microchip assays and the effects could be minimized by diluting the samples before loading. With further improvements in sensitivity, reproducibility, usability, assay process simplification, and incorporation of portable time-resolved fluorescence reader, Europium nanoparticle immunoassay technology could be adapted to meet the challenges of point-of-care diagnosis of HIV or other health-threatening pathogens at bedside or in resource-limited settings.

  8. Recent advances in the analysis of therapeutic proteins by capillary and microchip electrophoresis.

    PubMed

    Creamer, Jessica S; Oborny, Nathan J; Lunte, Susan M

    2014-07-01

    The development of therapeutic proteins and peptides is an expensive and time-intensive process. Biologics, which have become a multi-billion dollar industry, are chemically complex products that require constant observation during each stage of development and production. Post-translational modifications along with chemical and physical degradation from oxidation, deamidation, and aggregation, lead to high levels of heterogeneity that affect drug quality and efficacy. The various separation modes of capillary electrophoresis (CE) are commonly utilized to perform quality control and assess protein heterogeneity. This review attempts to highlight the most recent developments and applications of CE separation techniques for the characterization of protein and peptide therapeutics by focusing on papers accepted for publication in the in the two-year period between January 2012 and December 2013. The separation principles and technological advances of CE, capillary gel electrophoresis, capillary isoelectric focusing, capillary electrochromatography and CE-mass spectrometry are discussed, along with exciting new applications of these techniques to relevant pharmaceutical issues. Also included is a small selection of papers on microchip electrophoresis to show the direction this field is moving with regards to the development of inexpensive and portable analysis systems for on-site, high-throughput analysis.

  9. Recent advances in the analysis of therapeutic proteins by capillary and microchip electrophoresis

    PubMed Central

    Creamer, Jessica S.; Oborny, Nathan J.; Lunte, Susan M.

    2014-01-01

    The development of therapeutic proteins and peptides is an expensive and time-intensive process. Biologics, which have become a multi-billion dollar industry, are chemically complex products that require constant observation during each stage of development and production. Post-translational modifications along with chemical and physical degradation from oxidation, deamidation, and aggregation, lead to high levels of heterogeneity that affect drug quality and efficacy. The various separation modes of capillary electrophoresis (CE) are commonly utilized to perform quality control and assess protein heterogeneity. This review attempts to highlight the most recent developments and applications of CE separation techniques for the characterization of protein and peptide therapeutics by focusing on papers accepted for publication in the in the two-year period between January 2012 and December 2013. The separation principles and technological advances of CE, capillary gel electrophoresis, capillary isoelectric focusing, capillary electrochromatography and CE-mass spectrometry are discussed, along with exciting new applications of these techniques to relevant pharmaceutical issues. Also included is a small selection of papers on microchip electrophoresis to show the direction this field is moving with regards to the development of inexpensive and portable analysis systems for on-site, high-throughput analysis. PMID:25126117

  10. Detection of hexavalent uranium with inline and field-portable immunosensors

    SciTech Connect

    Melton, Scott J.; Yu, Haini; Ali, Mehnaaz F.; Williams, Kenneth H; Wilkins, Michael J.; Long, Philip E.; Blake, Diane A.

    2008-10-02

    An antibody that recognizes a chelated form of hexavalent uranium was used in the development of two different immunosensors for uranium detection. Specifically, these sensors were utilized for the analysis of groundwater samples collected during a 2007 field study of in situ bioremediation in a aquifer located at Rifle, CO. The antibody-based sensors provided data comparable to that obtained using Kinetic Phosphorescence Analysis (KPA). Thus, these novel instruments and associated reagents should provide field researchers and resource managers with valuable new tools for on-site data acquisition.

  11. DETECTION AND IDENTIFICATION OF TOXIC AIR POLLUTANTS USING FIELD PORTABLE AND AIRBORNE REMOTE IMAGING SYSTEMS

    EPA Science Inventory

    Remote sensing technologies are a class of instrument and sensor systems that include laser imageries, imaging spectrometers, and visible to thermal infrared cameras. These systems have been successfully used for gas phase chemical compound identification in a variety of field e...

  12. Field portable detection of VOCs using a SAW/GC system

    SciTech Connect

    Staples, E.J.

    1995-10-01

    This paper describes research on a fast gas chromatography (GC) vapor analysis system which uses a new type of Surface Acoustic Wave detector technology to characterize organic contamination in soil and groundwater. The project was sponsored by the Department of Energy, Morgantown Energy Technology Center. The instrument was field tested at the Savannah River Plant.

  13. Technical design issues for a field-portable supercritical fluid extractor

    SciTech Connect

    Wright, B.W.; Zemanian, T.S.; Robins, W.H.; Wright, C.W.

    1995-01-01

    Supercritical fluid extraction is gaining acceptance as an alternative sample preparation method for trace organic analysis. The development of SFE instrumentation optimized for field use requires taking several technical design issues including size and weight requirements, user-friendly operation, and technical performance capabilities into consideration. Parameters associated with a prototype SFE instrument under development for potential use in conducting on-site inspections of the Chemical Weapons Convention and its preliminary technical and operational performance are described.

  14. Practical considerations for the field application of miniaturized portable Raman instrumentation for the identification of minerals.

    PubMed

    Vítek, Petr; Jehlička, Jan; Edwards, Howell G M

    2013-07-01

    The nondestructive identification of both inorganic and organic compounds without the need for chemical or mechanical sample preparation is an advantage of the Raman spectroscopic analytical technique when applied in situ using miniaturized equipment for the geosciences. This is critically assessed here for several real life geoscientific scenarios in which several groups of minerals were analyzed with emphasis on evaporites, carbonates, and selected types of dark minerals and weak Raman scatterers. The role of individual analytical instrumental parameters such as focal plane precision, exposure time, and ambient light conditions that can affect the acquisition and interpretation of spectroscopic data from these specimens in field conditions was also evaluated. PMID:23816130

  15. Practical considerations for the field application of miniaturized portable Raman instrumentation for the identification of minerals.

    PubMed

    Vítek, Petr; Jehlička, Jan; Edwards, Howell G M

    2013-07-01

    The nondestructive identification of both inorganic and organic compounds without the need for chemical or mechanical sample preparation is an advantage of the Raman spectroscopic analytical technique when applied in situ using miniaturized equipment for the geosciences. This is critically assessed here for several real life geoscientific scenarios in which several groups of minerals were analyzed with emphasis on evaporites, carbonates, and selected types of dark minerals and weak Raman scatterers. The role of individual analytical instrumental parameters such as focal plane precision, exposure time, and ambient light conditions that can affect the acquisition and interpretation of spectroscopic data from these specimens in field conditions was also evaluated.

  16. Optical low-cost and portable arrangement for full field 3D displacement measurement using a single camera

    NASA Astrophysics Data System (ADS)

    López-Alba, E.; Felipe-Sesé, L.; Schmeer, S.; Díaz, F. A.

    2016-11-01

    In the current paper, an optical low-cost system for 3D displacement measurement based on a single camera and 3D digital image correlation is presented. The conventional 3D-DIC set-up based on a two-synchronized-cameras system is compared with a proposed pseudo-stereo portable system that employs a mirror system integrated in a device for a straightforward application achieving a novel handle and flexible device for its use in many scenarios. The proposed optical system splits the image by the camera into two stereo images of the object. In order to validate this new approach and quantify its uncertainty compared to traditional 3D-DIC systems, solid rigid in and out-of-plane displacements experiments have been performed and analyzed. The differences between both systems have been studied employing an image decomposition technique which performs a full image comparison. Therefore, results of all field of view are compared with those using a stereoscopy system and 3D-DIC, discussing the accurate results obtained with the proposed device not having influence any distortion or aberration produced by the mirrors. Finally, the adaptability of the proposed system and its accuracy has been tested performing quasi-static and dynamic experiments using a silicon specimen under high deformation. Results have been compared and validated with those obtained from a conventional stereoscopy system showing an excellent level of agreement.

  17. Portable light-emitting diode-based photometer with one-shot optochemical sensors for measurement in the field.

    PubMed

    Palma, A J; Ortigosa, J M; Lapresta-Fernández, A; Fernández-Ramos, M D; Carvajal, M A; Capitán-Vallvey, L F

    2008-10-01

    This report describes the electronics of a portable, low-cost, light-emitting diode (LED)-based photometer dedicated to one-shot optochemical sensors. Optical detection is made through a monolithic photodiode with an on-chip single-supply transimpedance amplifier that reduces some drawbacks such as leakage currents, interferences, and parasitic capacitances. The main instrument characteristics are its high light source stability and thermal correction. The former is obtained by means of the optical feedback from the LED polarization circuit, implementing a pseudo-two light beam scheme from a unique light source with a built-in beam splitter. The feedback loop has also been used to adjust the LED power in several ranges. Moreover, the low-thermal coefficient achieved (-90 ppm/degrees C) is compensated by thermal monitoring and calibration function compensation in the digital processing. The hand-held instrument directly gives the absorbance ratio used as the analytical parameter and the analyte concentration after programming the calibration function in the microcontroller. The application of this photometer for the determination of potassium and nitrate, using one-shot sensors with ionophore-based chemistries is also demonstrated, with a simple analytical methodology that shortens the analysis time, eliminating some calibrating solutions (HCl, NaOH, and buffer). Therefore, this compact instrument is suitable for real-time analyte determination and operation in the field. PMID:19044700

  18. Performance evaluation of currently used portable X ray fluorescence instruments for measuring the lead content of paint in field samples.

    PubMed

    Muller, Yan; Favreau, Philippe; Kohler, Marcel

    2014-01-01

    Field-portable X-ray fluorescence (FP-XRF) instruments are important for non-destructive, rapid and convenient measurements of lead in paint, in view of potential remediation. Using real-life paint samples, we compared measurements from three FP-XRF instruments currently used in Switzerland with laboratory measurements using inductively coupled plasma mass spectrometry after complete sample dissolution. Two FP-XRF devices that functioned by lead L shell excitation frequently underestimated the lead concentration of samples. Lack of accuracy correlated with lead depth and/or the presence of additional metal elements (Zn, Ba or Ti). A radioactive source emitter XRF that enabled the additional K shell excitation showed higher accuracy and precision, regardless of the depth of the lead layer in the sample or the presence of other elements. Inspection of samples by light and electron microscopy revealed the diversity of real-life samples, with multi-layered paints showing various depths of lead and other metals. We conclude that the most accurate measurements of lead in paint are currently obtained with instruments that provide at least sufficient energy for lead K shell excitation.

  19. Metals in boat paint fragments from slipways, repair facilities and abandoned vessels: an evaluation using field portable XRF.

    PubMed

    Turner, Andrew; Comber, Sean; Rees, Aldous B; Gkiokas, Dimitrios; Solman, Kevin

    2015-01-01

    Paint flaking off abandoned vessels or generated during boat repair is hazardous to human health and wildlife. In this study, a means of screening paint fragments using a field portable-X-ray fluorescence (FP-XRF) spectrometer is described. The technique is capable of delivering rapid, surficial measurements of Ba, Cu, Pb and Zn down to concentrations less than 150 μg g(-1), and Sn and Cr to concentrations of a few hundred μg g(-1). Application of the technique to fragments collected from slipways, yards, hardstandings, abandoned boats and ships undergoing maintenance throughout the EU reveal highly variable concentrations of metals among samples from the same environment or from the same region of a given boat; in many cases, variability is also evident in different areas or on different surfaces of the same fragment. Of particular concern are elevated concentrations of substances that have been restricted or banned (e.g. Sn, an indicator of organotin, and up to concentrations of 40,000 μg g(-1), and Pb up to concentrations of 200,000 μg g(-1)). Although FP-XRF can rapidly screen samples whose composition and origin are unknown and can assist in instantaneous decision making, a full risk assessment will rely on additional analyses of the precise species (including organo-forms) of the metals present.

  20. Analysis of beverages for Hg, As, Pb, and Cd with a field portable X-ray fluorescence analyzer.

    PubMed

    Anderson, David L

    2010-01-01

    Analytical capabilities of a handheld X-ray tube analyzer for analysis of beverages were evaluated. Sets of standard solutions for the elements Hg, As, Pb, and Cd were prepared with mass fractions up to 5000 mg/kg. A thirst quencher beverage was spiked with these elements up to mass fractions of 2500 mg/kg. Portions of these solutions were placed in standard X-ray fluorescence (XRF) cells, as well as the original container, and analyzed by using a field portable Innov-X alpha-6000s XRF tube-type analyzer. Uncorrected analyzer output usually yielded qualitative or semiquantitative results for the spiked beverages in X-ray cells. Average correction factors applied to analyzer output yielded accurate (in terms of z-scores) quantitative results for As above 20 mg/kg and qualitative or semiquantitative results for the other elements. Weighted quadratic fit calibrations provided accurate quantitative or semiquantitative results for all elements at levels above 20 mg/kg. The instrument's preset X-ray overlap correction algorithm worked well for the beverage spiked with all four elements. Spiked beverages analyzed through the wall of the original polyethylene terephthalate container produced accurate results within measurement uncertainties after application of "container wall" correction factors.

  1. [Determination of Cr, Cu, Zn, Pb and As in soil by field portable X-ray fluorescence spectrometry].

    PubMed

    Lu, An-xiang; Wang, Ji-hua; Pan, Li-gang; Han, Ping; Han, Ying

    2010-10-01

    Total concentrations of Cr, Cu, Zn, Pb and As were determined in soil samples from Beijing, Xinjiang, Heilongjiang, Yunnan, and Jiangsu provinces, using field portable X-ray fluorescence spectrometry (XRF). The relationship between XRF analysis results and the concentration of heavy metals in soils was established. The influence of soil particle size and humidity was also considered. Experiments showed that the particle size of soil affected XRF performance. While particle size decreased from 420 to 180 microm, the relative standard deviation (RSD) of XRF detect results reduced from 15.6% to 6.9%. Soil humidity mainly affected the counts of XRF measured. As the soil water content increased from 5% to 252, the analysis result's relative ratio of humid soil samples to oven dried soil samples decreased from 86% to 69%, according with the equation I = 100e(0.015c), where I means relative ratio, and c means water content (R2 = 0.83, n=30). A high degree of linearity was found for all the five heavy metals with the XRF measurement in the range of 0 to 1500 mg x kg(-1). But the linearity equation was not the same among these soils. The linearity equation established with Yunnan soil has a small slope because of higher Fe concentration in soil. The performance of instrument was assessed by comparing XRF analysis result with the standard sample reference, and the result showed that XRF is an effective tool for rapid, quantitative monitoring of soil metal contamination.

  2. Feasibility of a portable morphological scene change detection security system for field programmable gate arrays (FPGA)

    NASA Astrophysics Data System (ADS)

    Tickle, Andrew J.; Smith, Jeremy S.; Wu, Q. Henry

    2008-04-01

    In this paper, there is an investigation into the possibility of executing a Morphological Scene Change Detection (MSCD) system on a Field Programmable Gate Array (FPGA), which would allow its set up in virtually any location, with its purpose to detect intruders and raise an alarm to call security personal, and a signal to initial a lockdown of the local area. This paper will include how the system was scaled down from the full building multi-computer system, to an FPGA without losing any functionality using Altera's DSP Builder development tool. Also included is the analysis of the different situations which the system would encounter in the field, and their respective alarm triggering levels, these include indoors, outdoors, close-up, distance, high-brightness, low-light, bad weather, etc. The triggering mechanism is a pixel counter and threshold system, and its adaptive design will be included. All the results shown in this paper, will also be verified by MATLAB m-files running on a full desktop PC, to show that the results obtained from the FPGA based system are accurate.

  3. Field-Portable Immunoassay Instruments and Reagents to Measure Chelators and Mobile Forms of Uranium

    SciTech Connect

    Blake, Diane A.

    2003-06-01

    The goals for the 3-year project period are (1) to test and validate the present uranium sensor and develop protocols for its use at the NABIR Field Research Center; (2) to develop new reagents that will provide superior performance for the present hand-held immunosensor; and (3) to develop new antibodies that will permit this sensor to also measure other environmental contaminants (chromium, mercury, and/or DTPA). Sensor design modifications are underway via international collaborations. New reagents that will provide superior performance for the present hand-held immunosensor are being prepared and tested. New methods have been developed, to produce recombinant forms of metal-specific monoclonal antibodies for use with the sensor. Site-directed mutagenesis experiments are underway to determine the mechanisms of binding. Immunization experiments with sheep and rabbits to develop new recombinant forms of antibodies to metal-chelate complexes (chromium, mercury, and/or DTPA) have been initiated.

  4. Recent developments in optical detection methods for microchip separations.

    PubMed

    Götz, Sebastian; Karst, Uwe

    2007-01-01

    This paper summarizes the features and performances of optical detection systems currently applied in order to monitor separations on microchip devices. Fluorescence detection, which delivers very high sensitivity and selectivity, is still the most widely applied method of detection. Instruments utilizing laser-induced fluorescence (LIF) and lamp-based fluorescence along with recent applications of light-emitting diodes (LED) as excitation sources are also covered in this paper. Since chemiluminescence detection can be achieved using extremely simple devices which no longer require light sources and optical components for focusing and collimation, interesting approaches based on this technique are presented, too. Although UV/vis absorbance is a detection method that is commonly used in standard desktop electrophoresis and liquid chromatography instruments, it has not yet reached the same level of popularity for microchip applications. Current applications of UV/vis absorbance detection to microchip separations and innovative approaches that increase sensitivity are described. This article, which contains 85 references, focuses on developments and applications published within the last three years, points out exciting new approaches, and provides future perspectives on this field. PMID:17031620

  5. Field-usable portable analyzer for chlorinated organic compounds. Topical report, September 1992--May 1994

    SciTech Connect

    Buttner, W.J.; Williams, R.D.

    1995-05-01

    Through a U.S. DOE-funded program, an advanced chlorinated organic (RCL) vapor monitor has been built and tested in actual hazardous waste site operations. The monitor exploits the analytical capabilities of a solid-state sensor which was recently developed and has remarkable selectivity for chlorinated organic vapors at sub-parts-per-million sensitivity. The basic design goal of a user-friendly, reliable, instrument with a broad dynamic range for the selective detection of chlorinated solvent vapors was demonstrated. To date, no non-halogen-containing compound has been identified that induces a measurable response on the sensor, including commonly encountered contaminants such as BTXs (benzene, toluene, and xylenes) or POLs (petroleum, oils, lubricants). In addition to the development of the RCL MONITOR, advanced sampler systems were developed to further extend the analytical capability of this instrument, allowing chemical analyses to be performed for both vapor phase and condensed contamination. The sampling methods include fixed dilution, preconcentration, and closed-loop air stripping for condensed media. With uniform success, these different series of field tests were conducted at DOE facilities on several types of samples. Independent cost-benefit analysis has concluded that significant cost savings can be achieved using the RCL MONITOR in DOE applications. This effort provides a sound fundamental technology base for the development of advanced analytical methods that are needed by the US DOE. In addition, advanced methods for detecting chlorinated hydrocarbons that are made possible by this technology will save time, reduce costs, and improve human health and safety in restoration operations. To fully achieve all possible cost savings, continued effort is necessary to develop validated methods for the use of the RCL MONITOR. The development of methods through case studies is the theme of the Phase II effort, which is currently underway.

  6. Field detection of avian influenza virus in wild birds: evaluation of a portable rRT-PCR system and freeze-dried reagents

    USGS Publications Warehouse

    Takekawa, John Y.; Iverson, Samuel A.; Schultz, Annie K.; Hill, Nichola J.; Cardona, Carol J.; Boyce, Walter M.; Dudley, Joseph P.

    2010-01-01

    Wild birds have been implicated in the spread of highly pathogenic avian influenza (HPAIV) of the H5N1 subtype, prompting surveillance along migratory flyways. Sampling of wild birds is often conducted in remote regions, but results are often delayed because of limited local analytical capabilities, difficulties with sample transportation and permitting, or problems keeping samples cold in the field. In response to these challenges, the performance of a portable real-time, reverse transcriptase-polymerase chain reaction (rRT-PCR) unit (RAPID(Registered), Idaho Technologies, Salt Lake City, UT) that employed lyophilized reagents (Influenza A Target 1 Taqman; ASAY-ASY-0109, Idaho Technologies) was compared to virus isolation combined with real-time RT-PCR conducted in a laboratory. This study included both field and experimental-based sampling. Field samples were collected from migratory shorebirds captured in northern California, while experimental samples were prepared by spiking fecal material with an H6N2 AIV isolate. Results indicated that the portable rRT-PCR unit had equivalent specificity to virus isolation with no false positives, but sensitivity was compromised at low viral titers. Use of portable rRT-PCR with lyophilized reagents may expedite surveillance results, paving the way to a better understanding of wild bird involvement in HPAIV H5N1 transmission.

  7. Field Analysis of Polychlorinated Biphenyls (PCBs) in Soil Using Solid-Phase Microextraction (SPME) and a Portable Gas Chromatography-Mass Spectrometry System.

    PubMed

    Zhang, Mengliang; Kruse, Natalie A; Bowman, Jennifer R; Jackson, Glen P

    2016-05-01

    An expedited field analysis method was developed for the determination of polychlorinated biphenyls (PCBs) in soil matrices using a portable gas chromatography-mass spectrometry (GC-MS) instrument. Soil samples of approximately 0.5 g were measured with a portable scale and PCBs were extracted by headspace solid-phase microextraction (SPME) with a 100 µm polydimethylsiloxane (PDMS) fiber. Two milliliters of 0.2 M potassium permanganate and 0.5 mL of 6 M sulfuric acid solution were added to the soil matrices to facilitate the extraction of PCBs. The extraction was performed for 30 min at 100 ℃ in a portable heating block that was powered by a portable generator. The portable GC-MS instrument took less than 6 min per analysis and ran off an internal battery and helium cylinder. Six commercial PCB mixtures, Aroclor 1016, 1221, 1232, 1242, 1248, 1254, and 1260, could be classified based on the GC chromatograms and mass spectra. The detection limit of this method for Aroclor 1260 in soil matrices is approximately 10 ppm, which is sufficient for guiding remediation efforts in contaminated sites. This method was applicable to the on-site analysis of PCBs with a total analysis time of 37 min per sample. However, the total analysis time could be improved to less than 7 min per sample by conducting the rate-limiting extraction step for different samples in parallel. PMID:27170778

  8. Field Analysis of Polychlorinated Biphenyls (PCBs) in Soil Using Solid-Phase Microextraction (SPME) and a Portable Gas Chromatography-Mass Spectrometry System.

    PubMed

    Zhang, Mengliang; Kruse, Natalie A; Bowman, Jennifer R; Jackson, Glen P

    2016-05-01

    An expedited field analysis method was developed for the determination of polychlorinated biphenyls (PCBs) in soil matrices using a portable gas chromatography-mass spectrometry (GC-MS) instrument. Soil samples of approximately 0.5 g were measured with a portable scale and PCBs were extracted by headspace solid-phase microextraction (SPME) with a 100 µm polydimethylsiloxane (PDMS) fiber. Two milliliters of 0.2 M potassium permanganate and 0.5 mL of 6 M sulfuric acid solution were added to the soil matrices to facilitate the extraction of PCBs. The extraction was performed for 30 min at 100 ℃ in a portable heating block that was powered by a portable generator. The portable GC-MS instrument took less than 6 min per analysis and ran off an internal battery and helium cylinder. Six commercial PCB mixtures, Aroclor 1016, 1221, 1232, 1242, 1248, 1254, and 1260, could be classified based on the GC chromatograms and mass spectra. The detection limit of this method for Aroclor 1260 in soil matrices is approximately 10 ppm, which is sufficient for guiding remediation efforts in contaminated sites. This method was applicable to the on-site analysis of PCBs with a total analysis time of 37 min per sample. However, the total analysis time could be improved to less than 7 min per sample by conducting the rate-limiting extraction step for different samples in parallel.

  9. Can field portable X-ray fluorescence (pXRF) produce high quality data for application in environmental contamination research?

    PubMed

    Rouillon, Marek; Taylor, Mark P

    2016-07-01

    This research evaluates the analytical capabilities of a field portable X-ray fluorescence spectrometer (pXRF) for the measurement of contaminated soil samples using a matrix-matched calibration. The calibrated pXRF generated exceptional data quality from the measurement of ten soil reference materials. Elemental recoveries improved for all 11 elements post-calibration with reduced measurement variation and detection limits in most cases. Measurement repeatability of reference values ranged between 0.2 and 10% relative standard deviation, while the majority (82%) of reference recoveries were between 90 and 110%. Definitive data quality, the highest of the US EPA's three level quality ranking, was achieved for 15 of 19 elemental datasets. Measurement comparability against inductively coupled plasma atomic emission spectrometry (ICP-AES) values was excellent for most elements (e.g, r(2) 0.999 for Mn and Pb, r(2) > 0.995 for Cu, Zn and Cd). Parallel measurement of reference materials revealed ICP-AES and ICP-MS measured Ti and Cr poorly when compared to pXRF. Individual recoveries of soil reference materials by both ICP-AES and pXRF showed that pXRF was equivalent to or better than ICP-AES values for all but two elements (Ni, As). This study demonstrates pXRF as a suitable alternative to ICP-AES analysis in the measurement of Ti, Cr, Mn, Fe, Cu, Zn, Sr, Cd, and Pb in metal-contaminated soils. Where funds are limited, pXRF provides a low-cost, high quality solution to increasing sample density for a more complete geochemical investigation.

  10. FieldSpec: A field portable mass spectrometer prototype for high frequency measurements of δ (2) H and δ (18) O ratios in water

    NASA Astrophysics Data System (ADS)

    López Días, Veneranda; Quang Hoang, Hung; Martínez-Carreras, Núria; Barnich, François; Wirtz, Tom; Pfister, Laurent; McDonnell, Jeffrey

    2016-04-01

    Hydrological studies relying on stable water isotopes to better understand water sources, flowpaths and transit times are currently limited by the coarse temporal resolution of sampling and analysis protocols. At present, two kinds of lab-based instruments are used : (i) the standard isotope ratio mass spectrometers (IRMS) [1] and (ii) the laser-based instruments [2, 3]. In both cases, samples need to be collected in the field and then transferred to the laboratory for the water isotopic ratio measurements (even further complex sample preparation is required for the IRMS). Hence, past and ongoing research targets the development of field deployable instruments for measuring stable water isotopes at high temporal frequencies. While recent studies have demonstrated that laser-based instruments may be taken to the field [4, 5], their size and power consumption still restrict their use to sites equipped with mains power or generators. Here, we present progress on the development of a field portable mass spectrometer (FieldSpec) for direct high frequency measurements of δ2H and δ18O ratios in water. The FieldSpec instrument is based upon the use of a double focusing magnetic sector mass spectrometer in combination with an electron impact ion source and a membrane dual inlet system. The instrument directly collects liquid water samples in the field, which are then converted into water vapour before being injected into the mass spectrometer for the stable isotope analysis. δ2H and δ18O are derived from the measured mass spectra. All the components are arranged in a vacuum case having a suit case type dimension with portable electronics and battery. Proof-of-concept experiments have been carried out to characterize the instrument. The results show that the FieldSpec instrument has good linearity (R2 = 0.99). The reproducibility of the instrument ranges between 1 and 4 ‰ for δ2H and between 0.1 and 0.4 ‰ for δ18O isotopic ratio measurements. A measurement

  11. In situ monitoring (field screening) and assessment of lead and arsenic contaminants in the greater New Orleans area using a portable X-ray fluorescence analyser.

    PubMed

    Chou, Ju; Elbers, Don; Clement, Garrett; Bursavich, Bradley; Tian, Tian; Zhang, Wendy; Yang, Ke

    2010-09-01

    This paper reports environmental assessment and identification of environmental contaminants caused by exposure to toxic metals such as Pb and As after Hurricane Katrina using an onsite analysis method. Concentrations of lead (Pb) and arsenic (As) detected in many soil samples after Hurricane Katrina were reported to exceed EPA allowable value. Toxic metals mentioned above were measured by a portable X-ray fluorescence analyzer (XRF) in the greater New Orleans area. The portable XRF analyzer provides rapid data collection in the field. Distribution of Pb in New Orleans is displayed in a regional map using geographic information system (GIS). The map provides an updated image of environmental exposure to Pb contamination in the greater New Orleans area after Hurricane Katrina and also shows Pb contaminated areas where Pb concentrations exceed the EPA allowable level. The portable XRF provides a rapid analysis method for toxic metals and can be used for the field screening of soils at any place and for identifying contamination areas rapidly. PMID:20601988

  12. In situ monitoring (field screening) and assessment of lead and arsenic contaminants in the greater New Orleans area using a portable X-ray fluorescence analyser.

    PubMed

    Chou, Ju; Elbers, Don; Clement, Garrett; Bursavich, Bradley; Tian, Tian; Zhang, Wendy; Yang, Ke

    2010-09-01

    This paper reports environmental assessment and identification of environmental contaminants caused by exposure to toxic metals such as Pb and As after Hurricane Katrina using an onsite analysis method. Concentrations of lead (Pb) and arsenic (As) detected in many soil samples after Hurricane Katrina were reported to exceed EPA allowable value. Toxic metals mentioned above were measured by a portable X-ray fluorescence analyzer (XRF) in the greater New Orleans area. The portable XRF analyzer provides rapid data collection in the field. Distribution of Pb in New Orleans is displayed in a regional map using geographic information system (GIS). The map provides an updated image of environmental exposure to Pb contamination in the greater New Orleans area after Hurricane Katrina and also shows Pb contaminated areas where Pb concentrations exceed the EPA allowable level. The portable XRF provides a rapid analysis method for toxic metals and can be used for the field screening of soils at any place and for identifying contamination areas rapidly.

  13. Impact of portable air filtration units on exposure of haematology-oncology patients to airborne Aspergillus fumigatus spores under field conditions.

    PubMed

    Engelhart, S; Hanfland, J; Glasmacher, A; Krizek, L; Schmidt-Wolf, I G H; Exner, M

    2003-08-01

    We undertook a one-year study to investigate the impact of the NSA model 7100A/B portable air filtration unit on exposure of haematology-oncology patients to airborne Aspergillus fumigatus spores under field conditions. Weekly measurements for airborne A. fumigatus were conducted in indoor and outdoor air, and surveillance for invasive aspergillosis was based on a combination of ward liaison, targeted chart review and consultation with the medical staff. The mean indoor A. fumigatus counts (8.1 cfu/m3; range, <0.8 to 42 cfu/m3) reflected the fungal load of outdoor air (9.4 cfu/m3; range, <0.8 to 50 cfu/m3), and were reduced by only about one third in rooms with portable air filtration units (5.3 cfu/m3; range, <0.8 to 41 cfu/m3). During the study period, a total of five cases (incidence density, 0.8 per 1000 patient-days) of invasive aspergillosis (one proven case, four suspected cases; case fatality rate 40%) were recorded. None of these five patients was allocated to a room with portable air filtration unit, however, the difference between incidence densities in rooms with and without portable air filtration units was non-significant (Fisher's exact test, P=0.33). Due to the noise level and thermal discomfort, patient compliance with the air filtration units was poor. We conclude that under field conditions this air filtration unit cannot be recommended for prevention of invasive aspergillosis in neutropenic haematology-oncology patients.

  14. A review of microdialysis coupled to microchip electrophoresis for monitoring biological events.

    PubMed

    Saylor, Rachel A; Lunte, Susan M

    2015-02-20

    Microdialysis is a powerful sampling technique that enables monitoring of dynamic processes in vitro and in vivo. The combination of microdialysis with chromatographic or electrophoretic methods with selective detection yields a "separation-based sensor" capable of monitoring multiple analytes in near real time. For monitoring biological events, analysis of microdialysis samples often requires techniques that are fast (<1 min), have low volume requirements (nL-pL), and, ideally, can be employed on-line. Microchip electrophoresis fulfills these requirements and also permits the possibility of integrating sample preparation and manipulation with detection strategies directly on-chip. Microdialysis coupled to microchip electrophoresis has been employed for monitoring biological events in vivo and in vitro. This review discusses technical considerations for coupling microdialysis sampling and microchip electrophoresis, including various interface designs, and current applications in the field. PMID:25637011

  15. A review of microdialysis coupled to microchip electrophoresis for monitoring biological events

    PubMed Central

    Saylor, Rachel A.; Lunte, Susan M.

    2015-01-01

    Microdialysis is a powerful sampling technique that enables monitoring of dynamic processes in vitro and in vivo. The combination of microdialysis with chromatographic or electrophoretic methods yields along with selective detection methods yields a “separation-based sensor” capable of monitoring multiple analytes in near real time. Analysis of microdialysis samples requires techniques that are fast (<1 min), have low volume requirements (nL–pL), and, ideally, can be employed on-line. Microchip electrophoresis fulfills these requirements and also permits the possibility of integrating sample preparation and manipulation with detection strategies directly on-chip. Microdialysis coupled to microchip electrophoresis has been employed for monitoring biological events in vivo and in vitro. This review discusses technical considerations for coupling microdialysis sampling and microchip electrophoresis, including various interface designs, and current applications in the field. PMID:25637011

  16. A review of microdialysis coupled to microchip electrophoresis for monitoring biological events.

    PubMed

    Saylor, Rachel A; Lunte, Susan M

    2015-02-20

    Microdialysis is a powerful sampling technique that enables monitoring of dynamic processes in vitro and in vivo. The combination of microdialysis with chromatographic or electrophoretic methods with selective detection yields a "separation-based sensor" capable of monitoring multiple analytes in near real time. For monitoring biological events, analysis of microdialysis samples often requires techniques that are fast (<1 min), have low volume requirements (nL-pL), and, ideally, can be employed on-line. Microchip electrophoresis fulfills these requirements and also permits the possibility of integrating sample preparation and manipulation with detection strategies directly on-chip. Microdialysis coupled to microchip electrophoresis has been employed for monitoring biological events in vivo and in vitro. This review discusses technical considerations for coupling microdialysis sampling and microchip electrophoresis, including various interface designs, and current applications in the field.

  17. Application of field portable X-ray fluorescence spectrometry to rapidly measure metal distributions in sediment cores

    NASA Astrophysics Data System (ADS)

    Kenna, T. C.; Nitsche, F. O.; Sands, E.; Bell, R. E.; Ryan, W. B.; Chillrud, S. N.; Ross, J. M.

    2006-12-01

    This paper describes a technique to rapidly assess sediment deposition on split, wet sediment cores shortly after collection and prior to the commencement of further analyses. To identify sediments impacted by twentieth century activities, we use down-core sediment distributions of lead as a proxy to identify sediments deposited within the last ~100 years. Increases in the concentration of lead and other industrial metals have been used in numerous studies to provide constraints on deposition timing. The timing of the majority of industrial activities generally overlaps with the period of the 20th century. As a result, elevated lead concentrations in sediments also allow the identification of sediments that likely contain other anthropogenic particle-reactive contaminants of concern. Our approach entails the measurement of lead and several other elements using an Innov-X Field Portable x- ray fluorescence spectrometer (XRF). Measurements are made at 5-10cm increments on split, wet sediment cores. Using in-situ wet-bulk density estimates obtained from our core logging system, we are able to calculate water content and correct XRF measurements to a dry weight basis. Confirmatory analyses performed on discrete sub-samples using established protocols that employ wet/dry determinations for water content, homogenization by grinding, total-digestion, and determination by ICP-MS indicate good agreement between the two techniques (r2 = 0.9183; n=24; p<0.0001). Based on deposition chronologies provided by excess Pb-210 and Cs-137, we use the presence of lead concentrations in sediments above natural background levels (~20ppm) as a proxy for identifying those sediments impacted by 20th century activities. Results from a sediment core collected in Haverstraw Bay indicate that environmental lead levels began to rise above natural background in the 1930s. Work to evaluate the instrument's suitability with regard to measuring additional elements in both wet and dry sediments and

  18. Field Test Report: NETL Portable Raman Gas Composition Monitor - Initial Industrial tests at NETL and General Electric (GE)

    SciTech Connect

    Michael, Buric; Jessica, Mullen; Steven, Woodruff; Ben, Chorpening

    2012-02-24

    NETL has developed new technology which enables the use of Raman spectroscopy in the real-time measurement of gas mixtures. This technology uses a hollow reflective metal-lined capillary waveguide as a gas sampling cell which contains the sample gas, and efficiently collects optical Raman scattering from the gas sample, for measurement with a miniature spectrometer. The result is an optical Raman “fingerprint” for each gas which is tens or hundreds of times larger than that which can be collected with conventional free-space optics. In this manner, the new technology exhibits a combination of measurement speed and accuracy which is unprecedented for spontaneous Raman measurements of gases. This makes the system especially well-suited to gas turbine engine control based on a-priori measurement of incoming fuel composition. The system has been developed to produce a measurement of all of the common components of natural gas, including the lesser nitrogen, oxygen, carbon-dioxide, and carbon monoxide diluents to better than 1% concentration accuracy each second. The objective of this task under CRADA 10-N100 was to evaluate the capability of a laser Raman capillary gas sensor for combustion fuels. A portable version of the Raman gas sensor, constructed at NETL, was used for field-trials conducted in a cooperative research effort at a GE facility. Testing under the CRADA was performed in 5 parts. Parts 1-4 were successful in testing of the Raman Gas Composition Monitor with bottled calibration gases, and in continuous monitoring of several gas streams at low pressure, in comparison with an online mass spectrometer. In part 5, the Raman Gas Composition Monitor was moved outdoors for testing with high pressure gas supplies. Some difficulties were encountered during industrial testing including the condensation of heavy hydrocarbons inside the sample cell (in part 5), communication with the GE data collection system, as well as some drift in the optical noise

  19. Evaluation of field-portable X-ray fluorescence spectrometry for the determination of lead contamination on small-arms firing ranges

    SciTech Connect

    Schneider, J.F.; Taylor, J.D.; Bass, D.A.; Zellmer, D.; Rieck, M.

    1995-02-01

    Field analytical methods for the characterization of lead contamination in soil are being developed. In this study, the usefulness of a commercially available, field-portable energy-dispersive X-ray fluorescence spectrometer (XRF) is evaluated for determining the extent of lead contamination in soils on small-arms firing ranges at a military installation. This field screening technique provides significant time and cost savings for the study of sites with lead-contaminated soil. Data obtained with the XRF unit in the field are compared with data obtained from soil samples analyzed in an analytical laboratory by inductively coupled plasma atomic emission spectroscopy. Results indicate that the field-portable XRF unit evaluated in this study provides data that are useful in determining the extent and relative magnitude of lead contamination. For the commercial unit used in this study, improvements in the spectral resolution and in the limit of detection would be required to make the unit more than just a screening tool.

  20. Application of portable gas chromatography-photo ionization detector combined with headspace sampling for field analysis of benzene, toluene, ethylbenzene, and xylene in soils.

    PubMed

    Zhou, You-Ya; Yu, Ji-Fang; Yan, Zeng-Guang; Zhang, Chao-Yan; Xie, Ya-Bo; Ma, Li-Qiang; Gu, Qing-Bao; Li, Fa-Sheng

    2013-04-01

    A method based on headspace (HS) sampling coupling with portable gas chromatography (GC) with photo ionization detector (PID) was developed for rapid determination of benzene, toluene, ethylbenzene, and xylenes (BTEX) in soils. Optimal conditions for HS gas sampling procedure were determined, and the influence of soil organic matter on the recovery of BTEX from soil was investigated using five representative Chinese soils. The results showed that the HS-portable-GC-PID method could be effectively operated at ambient temperature, and the addition of 15 ml of saturated NaCl solution in a 40-ml sampling vial and 60 s of shaking time for sample solution were optimum for the HS gas sampling procedure. The recoveries of each BTEX in soils ranged from 87.2 to 105.1 %, with relative standard deviations varying from 5.3 to 7.8 %. Good linearity was obtained for all BTEX compounds, and the detection limits were in the 0.1 to 0.8 μg kg(-1) range. Soil organic matter was identified as one of the principal elements that affect the HS gas sampling of BTEX in soils. The HS-portable-GC-PID method was successfully applied for field determination of benzene and toluene in soils of a former chemical plant in Jilin City, northeast China. Considering its satisfactory repeatability and reproducibility and particular suitability to be operated in ambient environment, HS sampling coupling with portable GC-PID is, therefore, recommended to be a suitable screening tool for rapid on-site determination of BTEX in soils.

  1. Portable Analyzer Based on Microfluidics, Nanoengineered Electrochemical Sensors

    SciTech Connect

    Wang, Joseph

    2003-06-01

    This report summarizes the NMSU activity over the first year of the project (i.e., the 11/03-8/04 period). This research effort aims at developing a portable analytical system for fast, sensitive, and inexpensive, on-site monitoring of toxic transition metals and radionuclides in contaminated DOE Sites. In accordance to our original objectives our studies have focused on various fundamental and practical aspects of microchip devices for monitoring metal contaminants. As described in this section, we have made a substantial progress, and introduced effective routes for improving the reliability of devices for field screening of toxic metals. This 11-mos activity has already resulted in 2 research papers (published or in press in major journals), and several invited presentations in major meetings. (Several more publications are expected in the late part of 2004.) The electrochemical sensors being investigated rely on the highly sensitive adsorptive stripping voltammetry (AdSV) technique to detect metal ions of interest to the DOE, particularly uranium and chromium.

  2. Monitoring microbial community structure and dynamics during in situ U(VI) bioremediation with a field-portable microarray analysis system.

    PubMed

    Chandler, Darrell P; Kukhtin, Alexander; Mokhiber, Rebecca; Knickerbocker, Christopher; Ogles, Dora; Rudy, George; Golova, Julia; Long, Phil; Peacock, Aaron

    2010-07-15

    The objective of this study was to develop and validate a simple, field-portable, microarray system for monitoring microbial community structure and dynamics in groundwater and subsurface environments, using samples representing site status before acetate injection, during Fe-reduction, in the transition from Fe- to SO(4)(2-)-reduction, and into the SO(4)(2-)-reduction phase. Limits of detection for the array are approximately 10(2)-10(3) cell equivalents of DNA per reaction. Sample-to-answer results for the field deployment were obtained in 4 h. Retrospective analysis of 50 samples showed the expected progression of microbial signatures from Fe- to SO(4)(2-) -reducers with changes in acetate amendment and in situ field conditions. The microarray response for Geobacter was highly correlated with qPCR for the same target gene (R(2) = 0.84). Microarray results were in concordance with quantitative PCR data, aqueous chemistry, site lithology, and the expected microbial community response, indicating that the field-portable microarray is an accurate indicator of microbial presence and response to in situ remediation of a uranium-contaminated site.

  3. Recent advances in microchip electrophoresis for amino acid analysis.

    PubMed

    Ou, Gaozhi; Feng, Xiaojun; Du, Wei; Liu, Xin; Liu, Bi-Feng

    2013-10-01

    With the maturation of microfluidic technologies, microchip electrophoresis has been widely employed for amino acid analysis owing to its advantages of low sample consumption, reduced analysis time, high throughput, and potential for integration and automation. In this article, we review the recent progress in amino acid analysis using microchip electrophoresis during the period from 2007 to 2012. Innovations in microchip materials, surface modification, sample introduction, microchip electrophoresis, and detection methods are documented, as well as nascent applications of amino acid analysis in single-cell analysis, microdialysis sampling, food analysis, and extraterrestrial exploration. Without doubt, more applications of microchip electrophoresis in amino acid analysis may be expected soon.

  4. Recent advances in microchip electrophoresis for amino acid analysis.

    PubMed

    Ou, Gaozhi; Feng, Xiaojun; Du, Wei; Liu, Xin; Liu, Bi-Feng

    2013-10-01

    With the maturation of microfluidic technologies, microchip electrophoresis has been widely employed for amino acid analysis owing to its advantages of low sample consumption, reduced analysis time, high throughput, and potential for integration and automation. In this article, we review the recent progress in amino acid analysis using microchip electrophoresis during the period from 2007 to 2012. Innovations in microchip materials, surface modification, sample introduction, microchip electrophoresis, and detection methods are documented, as well as nascent applications of amino acid analysis in single-cell analysis, microdialysis sampling, food analysis, and extraterrestrial exploration. Without doubt, more applications of microchip electrophoresis in amino acid analysis may be expected soon. PMID:23436170

  5. Microchip-associated fibrosarcoma in a cat.

    PubMed

    Carminato, Antonio; Vascellari, Marta; Marchioro, Wendy; Melchiotti, Erica; Mutinelli, Franco

    2011-12-01

    A 9-year-old, neutered male cat was presented for a subcutaneous mass on the neck. After surgical removal of the mass, a pet identification microchip was found within the tumour. Histological examination of the mass revealed typical features of the feline postinjection sarcoma. The cat had never received injections at the tumour site; all routine vaccinations were administered in the hindlimbs. Few cases of sarcomas developing at the site of microchip application have been reported in animals, although the contributory role of vaccine administrations has not been ruled out. This is the first report of a microchip-associated fibrosarcoma in a cat. Adherence to American Association of Feline Practitioners vaccination guidelines, avoiding the interscapular area, enabled confirmation of the definitive aetiology of the neoplasia.

  6. Portable nucleic acid thermocyclers.

    PubMed

    Almassian, David R; Cockrell, Lisa M; Nelson, William M

    2013-11-21

    A nucleic acid thermal cycler is considered to be portable if it is under ten pounds, easily carried by one individual, and battery powered. Nucleic acid amplification includes both polymerase chain reaction (e.g. PCR, RT-PCR) and isothermal amplification (e.g. RPA, HDA, LAMP, NASBA, RCA, ICAN, SMART, SDA). There are valuable applications for portable nucleic acid thermocyclers in fields that include clinical diagnostics, biothreat detection, and veterinary testing. A system that is portable allows for the distributed detection of targets at the point of care and a reduction of the time from sample to answer. The designer of a portable nucleic acid thermocycler must carefully consider both thermal control and the detection of amplification. In addition to thermal control and detection, the designer may consider the integration of a sample preparation subsystem with the nucleic acid thermocycler. There are a variety of technologies that can achieve accurate thermal control and the detection of nucleic acid amplification. Important evaluation criteria for each technology include maturity, power requirements, cost, sensitivity, speed, and manufacturability. Ultimately the needs of a particular market will lead to user requirements that drive the decision between available technologies.

  7. Determination of the feasibility of using a portable X-ray fluorescence (XRF) analyzer in the field for measurement of lead content of sieved soil.

    PubMed

    Markey, Andrea M; Clark, C Scott; Succop, Paul A; Roda, Sandra

    2008-03-01

    Soil samples collected in housing areas with potential lead contamination generally are analyzed with flame atomic absorption spectrometry (FAAS) or other laboratory methods. Previous work indicates that field-portable X-ray fluorescence (XRF) analysis is capable of detecting soil lead levels comparable to those detected by FAAS in samples sieved to less than 125 microm in a laboratory. A considerable savings, both economical and in laboratory reporting time, would occur if a practical field method could be developed that does not require laboratory digestion and analysis. The XRF method also would provide immediate results that would facilitate the provision of information to residents and other interested parties more quickly than is possible with conventional laboratory methods. The goal of the study reported here was to determine the practicality of using the field-portable XRF analyzer for analysis of lead in soil samples that were sieved in the field. The practicality of using the XRF was determined by the amount of time it took to prepare and analyze the samples in the field and by the ease with which the procedure could be accomplished on site. Another objective of the study was to determine the effects of moisture on the process of sieving the soil. Seventy-eight samples were collected from 30 locations near 10 houses and were prepared and analyzed at the locations where they were collected. Mean soil lead concentrations by XRF were 816 ppm before drying and 817 ppm after drying, and by laboratory FAAS were 1,042 ppm. Correlation of field-portable XRF and FAAS results was excellent for samples sieved to less than 125 microm, with R2 values of .9902 and .992 before and after drying, respectively. The saturation ranged from 10 percent to 90 percent. At 65 percent saturation or higher, it was not feasible to sieve the soil in the field without a thorough drying step, since the soil would not pass through the sieve. Therefore the field method with sieving was

  8. Portable Analyzer Based on Microfluidics/Nanoengineered Electrochemical Sensors for in Situ Characterization of Mixed Wastes

    SciTech Connect

    Wang, Joseph

    2006-06-01

    Portable Analyzer Based on Microfluidic/Nanoengineered Electrochemical Sensors for in Situ Characterization of Mixed Wastes PI: Dr. Joseph Wang (In Collaboration with the PNNL PI Dr. Y. Lin). Objective of Research: This research effort aims at developing a portable analytical system for fast, sensitive, and inexpensive, on-site monitoring of toxic transition metals and radionuclides in contaminated DOE Sites. The portable devices will be based on Microscale Total Analytical systems ( -TAS) or 'Lab-on-a-chip' in combination with electrochemical (stripping-voltammetric) sensors. The resulting microfluidics/electrochemical sensor system would allow testing for toxic metals to be performed more rapidly, inexpensively, and reliably in a field setting. Progress Summary/Accomplishments: This report summarizes the ASU activity over the second year of the project. In accordance to our original objectives our studies have focused on various fundamental and practical aspects of sensing and microchip devices for monitoring metal contaminants. As described in this section, we have made a substantial progress, and introduced effective routes for improving the on-site detection of toxic metals and for interfacing microchips with the real world. This activity has already resulted in 7 research papers (published or in press in major international journals). The electrochemical sensors being developed rely on the highly sensitive adsorptive stripping voltammetry (AdSV) technique to detect metal ions of interest to the DOE, particularly uranium and chromium. Traditionally, AdSV measurements of U and Cr require the use of mercury electrodes which are not suitable attractive for field deployment. Our initial goal was thus to replace these toxic mercury electrodes with 'environmentally-friendly' sensor materials. In particular, we demonstrated recently that bismuth-film electrodes offer high-quality measurements of heavy metals that compare favorably with that of mercury electrodes

  9. Screening for volatile organic compounds in soil and groundwater by use of a portable gas chromatograph during field investigations at an Air Force installation in Ohio

    USGS Publications Warehouse

    Parnell, James M.

    1995-01-01

    The use of the portable gas chromatograph for screening of soil and water samples in the field was part of the drilling program for the installation of monitoring wells for a basewide ground-water monitoring program at Wright-Patterson Air Force Base, Ohio. Selected soil and ground-water samples were screened in the field for volatile organic compounds to determine if contamination was present, to define the vertical and lateral extent of contamination, and to aid in the placement of the well screens for optimal interception of contaminants. This report describes the screening methods, sample-collection, quality-assurance/quality-control methods, and data-interpretation procedures necessary for screening of soil and ground-water samples in the field during the water resources investigations.

  10. Evaluation of microchip material and surface treatment options for IEF of allergenic milk proteins on microchips.

    PubMed

    Poitevin, Martine; Shakalisava, Yuliya; Miserere, Sandrine; Peltre, Gabriel; Viovy, Jean-Louis; Descroix, Stephanie

    2009-12-01

    The use of glass and PDMS microchips has been investigated to perform rapid and efficient separation of allergenic whey proteins by IEF. To decrease EOF and to limit protein adsorption, two coating procedures have been compared. The first one consists in immobilizing hydroxypropyl cellulose (HPC) and the second one poly(dimethylacrylamide-co-allyl glycidyl ether) (PDMA-AGE). EOF limitation has been evaluated using frontal electrophoresis of a fluorescent marker of known effective mobility. EOF velocity was decreased by a factor about 100 and 30, respectively. pH gradient formation has been evaluated for each microchip using fluorescent pI markers. It was demonstrated that as expected a coating was essential to avoid pH gradient drift. Both coatings were efficient on glass microchips, but only PDMA-AGE allowed satisfying focusing of pI markers on PDMS microchips. Fluorescent covalent and noncovalent labelings of milk proteins have been compared by IEF on slab-gels. IEF separation of three major allergenic whey proteins [beta-lactoglobulin A (pI 5.25) and B (pI 5.35) and alpha-lactalbumin (pI 4.2-4.5)] was performed in both microchips. Milk proteins were separated with better resolution and shorter analysis time than by classical CIEF. Finally, better resolutions for milk allergens separation were obtained on glass microchips.

  11. Integration of cell phone imaging with microchip ELISA to detect ovarian cancer HE4 biomarker in urine at the point-of-care.

    PubMed

    Wang, Shuqi; Zhao, Xiaohu; Khimji, Imran; Akbas, Ragip; Qiu, Weiliang; Edwards, Dale; Cramer, Daniel W; Ye, Bin; Demirci, Utkan

    2011-10-21

    Ovarian cancer is asymptomatic in the early stages and most patients present with advanced levels of disease. The lack of cost-effective methods that can achieve frequent, simple and non-invasive testing hinders early detection and causes high mortality in ovarian cancer patients. Here, we report a simple and inexpensive microchip ELISA-based detection module that employs a portable detection system, i.e., a cell phone/charge-coupled device (CCD) to quantify an ovarian cancer biomarker, HE4, in urine. Integration of a mobile application with a cell phone enabled immediate processing of microchip ELISA results, which eliminated the need for a bulky, expensive spectrophotometer. The HE4 level detected by a cell phone or a lensless CCD system was significantly elevated in urine samples from cancer patients (n = 19) than healthy controls (n = 20) (p < 0.001). Receiver operating characteristic (ROC) analyses showed that the microchip ELISA coupled with a cell phone running an automated analysis mobile application had a sensitivity of 89.5% at a specificity of 90%. Under the same specificity, the microchip ELISA coupled with a CCD had a sensitivity of 84.2%. In conclusion, integration of microchip ELISA with cell phone/CCD-based colorimetric measurement technology can be used to detect HE4 biomarker at the point-of-care (POC), paving the way to create bedside technologies for diagnostics and treatment monitoring.

  12. Advances in Automation and Throughput of the Mars Organic Analyzer Microchip Capillary Electrophoresis System

    NASA Astrophysics Data System (ADS)

    Haldeman, B. J.; Skelley, A. M.; Scherer, J. R.; Jayarajah, C.; Mathies, R. A.

    2005-12-01

    We have previously demonstrated the design, construction and testing of a portable microchip capillary electrophoresis (CE) instrument called the Mars Organic Analyzer (MOA) for analysis of amino acids and amine containing organic molecules (1). This instrument is designed to accept organic compounds isolated from samples by sublimation or by subcritical water extraction, to label the amine groups with fluorescamine, and to perform high resolution electrophoretic analysis. The CE instrument has shown remarkable robustness during successful field tests last year in the Panoche Valley, CA (1) and more recently in the Atacama Desert, Chile (2). For successful operation on Mars, however, it is necessary to operate autonomously and to analyze large numbers of samples, blanks, and standards. Toward this end we present here two advances in the MOA system that test key aspects of an eventual flight prototype. First, we have developed an automated microfluidic system and method for the autonomous loading, running and cleaning of the CE chip on the single channel MOA instrument. The integration of microfabricated PDMS valves and pumps with all-glass separation channels in a multilayer design enabled creation of structures for complex fluidic routing. Twenty sequential analyses of an amino acid standard were performed with an automated cleaning procedure between runs. In addition, dilutions were performed on-chip, and blanks were run to demonstrate the elimination of carry-over from run to run. These results demonstrate an important advance of the technology readiness level of the MOA. Second, we have designed, constructed and successfully tested a lab version of the multichannel instrument we initially proposed for the MSL opportunity. The portable Multi-Channel Mars Organic Analyzer (McMOA, 25 by 30 by 15 cm), was designed to sequentially interrogate eight radially oriented CE separation channels on a single wafer. Since each channel can be used to analyze 20 or more

  13. A novel portable device to measure the temperature of both the inner and the outer tubes of a parabolic receiver in the field

    NASA Astrophysics Data System (ADS)

    Hermoso, J. L. Navarro; Espinosa-Rueda, Guillermo; Martinez, Noelia; Heras, Carlos; Osta, Marta

    2016-05-01

    The performance of parabolic trough (PT) receiver tubes (RT) has a direct impact on Solar Thermal Energy (STE) plant production. As a result, one major need of operation and maintenance (O&M) in STE plants is to monitor the state of the receiver tube as a key element in the solar field. However the lack of specific devices so far has limited the proper evaluation of operating receiver tubés thermal performance. As a consequence non-accurate approximations have been accepted until now using infrared thermal images of the glass outer tube. In order to fulfill this need, Abengoa has developed a unique portable device for evaluating the thermal performance and vacuum state of parabolic trough receiver tubes placed in the field. The novel device described in this paper, simultaneously provides the temperature of both the inner steel tube and the outer glass tube enabling a check on manufacturers specifications. The on-field evaluation of any receiver tube at any operating temperature has become possible thanks to this new measuring device. The features and usability of this new measurement system as a workable portable device in operating solar fields provide a very useful tool for all companies in the sector contributing to technology progress. The originality of the device, patent pending P201431969, is not limited to the CSP sector, also having scientific significance in the general measuring instruments field. This paper presents the work carried out to develop and validate the device, also detailing its functioning properties and including the excellent results obtained in the laboratory to determine its accuracy and standard deviation. This information was validated with data collected by O&M teams using this instrument in a commercial CSP plant. The relevance of the device has been evidenced by evaluating a wide sample of RT and the results are discussed in this paper. Finally, all the on field collected data is used to demonstrate the high impact that using

  14. On-Campus Projects: Inventing a Microchip.

    ERIC Educational Resources Information Center

    Basta, Nicholas

    1985-01-01

    In response to growth of microelectronics and changes in microchip design/manufacturing technology, universities are supporting class projects for students. Approximately 50 schools now conduct such programs which have resulted from earlier National Science Foundation sponsorship. Major advantages for the students include designing experience,…

  15. Elastomeric Microchip Electrospray Emitter for Stable Cone-Jet Mode Operation in the Nanoflow Regime.

    SciTech Connect

    Kelly, Ryan T.; Tang, Keqi; Irimia, Daniel; Toner, Mehmet; Smith, Richard D.

    2008-05-15

    Despite widespread interest in applying lab-on-a-chip technologies to mass spectrometry (MS)-based analyses, the coupling of microfluidics to electrospray ionization (ESI)-MS remains challenging. We report a robust, integrated poly(dimethylsiloxane) microchip interface for ESI-MS using simple and widely accessible microfabrication procedures. The interface uses an auxiliary channel to provide electrical contact in the Taylor cone of the electrospray without sample loss or dilution. The electric field at the channel terminus is enhanced by two vertical cuts that cause the interface to taper to a line rather than to a point, and the formation of small Taylor cones at the channel exit ensures sub-nL post-column dead volumes. While comparable ESI-MS sensitivities were achieved using both microchip and conventional fused silica capillary emitters, stable cone-jet mode electrospray could be established over a far broader range of flow rates (from 50–1000 nL/min) and applied potentials using the microchip emitters. This special feature of the microchip emitter should minimize the fine tuning required for electrospray optimization and make the stable electrospray more resistant to external perturbations.

  16. Recent applications of microchip electrophoresis to biomedical analysis.

    PubMed

    Nuchtavorn, Nantana; Suntornsuk, Worapot; Lunte, Susan M; Suntornsuk, Leena

    2015-09-10

    Many separation methods have been developed for biomedical analysis, including chromatographic (e.g. high performance liquid chromatography (HPLC) and gas chromatography (GC)) and electrophoretic methods (e.g. gel electrophoresis and capillary electrophoresis (CE)). Among these techniques, CE provides advantages in terms of high separation efficiency, simplicity, low sample and solvent volume consumption, short analysis time and applicability to a wide range of biomedically important substances. Microchip electrophoresis (ME) is a miniaturized platform of CE and is now considered as a simpler and more convenient alternative, which has demonstrated potential in analytical chemistry. High-throughput, cost-effective and portable analysis systems can be developed using ME. The current review describes different separation modes and detectors that have been employed in ME to analyze various classes of biomedical analytes (e.g. pharmaceuticals and related substances, nucleic acids, amino acids, peptides, proteins, antibodies and antigens, carbohydrates, cells, cell components and lysates). Recent applications (during 2010-2014) in these areas are presented in tables and some significant findings are highlighted. PMID:25840947

  17. Implementation of microchip electrophoresis instrumentation for future spaceflight missions.

    PubMed

    Willis, Peter A; Creamer, Jessica S; Mora, Maria F

    2015-09-01

    We present a comprehensive discussion of the role that microchip electrophoresis (ME) instrumentation could play in future NASA missions of exploration, as well as the current barriers that must be overcome to make this type of chemical investigation possible. We describe how ME would be able to fill fundamental gaps in our knowledge of the potential for past, present, or future life beyond Earth. Despite the great promise of ME for ultrasensitive portable chemical analysis, to date, it has never been used on a robotic mission of exploration to another world. We provide a current snapshot of the technology readiness level (TRL) of ME instrumentation, where the TRL is the NASA systems engineering metric used to evaluate the maturity of technology, and its fitness for implementation on missions. We explain how the NASA flight implementation process would apply specifically to ME instrumentation, and outline the scientific and technology development issues that must be addressed for ME analyses to be performed successfully on another world. We also outline research demonstrations that could be accomplished by independent researchers to help advance the TRL of ME instrumentation for future exploration missions. The overall approach described here for system development could be readily applied to a wide range of other instrumentation development efforts having broad societal and commercial impact.

  18. Recent applications of microchip electrophoresis to biomedical analysis.

    PubMed

    Nuchtavorn, Nantana; Suntornsuk, Worapot; Lunte, Susan M; Suntornsuk, Leena

    2015-09-10

    Many separation methods have been developed for biomedical analysis, including chromatographic (e.g. high performance liquid chromatography (HPLC) and gas chromatography (GC)) and electrophoretic methods (e.g. gel electrophoresis and capillary electrophoresis (CE)). Among these techniques, CE provides advantages in terms of high separation efficiency, simplicity, low sample and solvent volume consumption, short analysis time and applicability to a wide range of biomedically important substances. Microchip electrophoresis (ME) is a miniaturized platform of CE and is now considered as a simpler and more convenient alternative, which has demonstrated potential in analytical chemistry. High-throughput, cost-effective and portable analysis systems can be developed using ME. The current review describes different separation modes and detectors that have been employed in ME to analyze various classes of biomedical analytes (e.g. pharmaceuticals and related substances, nucleic acids, amino acids, peptides, proteins, antibodies and antigens, carbohydrates, cells, cell components and lysates). Recent applications (during 2010-2014) in these areas are presented in tables and some significant findings are highlighted.

  19. Field application of the Numobag as a portable disposable isolation unit and for treating chemical, radiological or biologically induced wounds.

    SciTech Connect

    Miller, Keith A.; Felton, Robert; Vaughan, Courtenay Thomas

    2005-04-01

    Numotech Inc. has developed the Numobag{trademark}, a disposable, lightweight, wound healing device which produces Topical Hyperbaric Oxygen Therapy (THOT). The Numobag{trademark} is cost effective and has been clinically validated to heal large skin lesions rapidly and has proven to arrest wound advancement from several insidious forms of biological attack including dermal anthrax, small pox, necrotizing fasciitis etc. The Numobag{trademark} can treat mass casualties wounded by chemical/radiological burns or damaging biological exposures. The Numobag{trademark} can be a frontline tool as an isolation unit, reducing cross-contamination and infection of medical personnel. The heightened oxygen content kills organisms on the skin and in the wound, avoids expensive hospital trash disposal procedures, and helps the flesh heal. The Numobag{trademark} requires high purity oxygen. Numotech Inc. is teaming with Sandia National Laboratories and Spektr Conversion in Russia to develop a cost effective, portable, low power oxygen generator.

  20. Comparison of surface and hydrogel-based protein microchips.

    PubMed

    Zubtsov, D A; Savvateeva, E N; Rubina, A Yu; Pan'kov, S V; Konovalova, E V; Moiseeva, O V; Chechetkin, V R; Zasedatelev, A S

    2007-09-15

    Protein microchips are designed for high-throughput evaluation of the concentrations and activities of various proteins. The rapid advance in microchip technology and a wide variety of existing techniques pose the problem of unified approach to the assessment and comparison of different platforms. Here we compare the characteristics of protein microchips developed for quantitative immunoassay with those of antibodies immobilized on glass surfaces and in hemispherical gel pads. Spotting concentrations of antibodies used for manufacturing of microchips of both types and concentrations of antigen in analyte solution were identical. We compared the efficiency of antibody immobilization, the intensity of fluorescence signals for both direct and sandwich-type immunoassays, and the reaction-diffusion kinetics of the formation of antibody-antigen complexes for surface and gel-based microchips. Our results demonstrate higher capacity and sensitivity for the hydrogel-based protein microchips, while fluorescence saturation kinetics for the two types of microarrays was comparable.

  1. Microchip capillary electrophoresis-electrospray ionization-mass spectrometry of intact proteins using uncoated Ormocomp microchips.

    PubMed

    Sikanen, Tiina; Aura, Susanna; Franssila, Sami; Kotiaho, Tapio; Kostiainen, Risto

    2012-01-20

    We present rapid (<5 min) and efficient intact protein analysis by mass spectrometry (MS) using fully microfabricated and monolithically integrated capillary electrophoresis-electrospray ionization (CE-ESI) microchips. The microchips are fabricated fully of commercial inorganic-organic hybrid material, Ormocomp, by UV-embossing and adhesive Ormocomp-Ormocomp bonding (CE microchannels). A sheath-flow ESI interface is monolithically integrated with the UV-embossed separation channels by cutting a rectangular emitter tip in the end with a dicing saw. As a result, electrospray was produced from the corner of chip with good reproducibility between parallel tips (stability within 3.8-9.2% RSD). Thanks to its inherent biocompatibility and stable (negative) surface charge, Ormocomp microchips enable efficient intact protein analysis with up to ∼10(4) theoretical separation plates per meter without any chemical or physical surface modification before analysis. The same microchip setup is also feasible for rapid peptide sequencing and mass fingerprinting and shows excellent migration time repeatability from run to run for both peptides (5.6-5.9% RSD, n=4) and intact proteins (1.3-7.5% RSD, n=3). Thus, the Ormocomp microchips provide a versatile new tool for MS-based proteomics. Particularly, the feasibility of the Ormocomp chips for rapid analysis of intact proteins with such a simple setup is a valuable increment to the current technology.

  2. Portable shift register

    SciTech Connect

    Halbig, J.K.; Bourret, S.C.; Hansen, W.J.; Hicks, D.V.; Klosterbuer, S.F.; Krick, M.S.

    1994-01-01

    An electronics package for a small, battery-operated, self-contained, neutron coincidence counter based on a portable shift-register (PSR) has been developed. The counter was developed for applications not adequately addressed by commercial packages, including in-plant measurements to demonstrate compliance with regulations (domestic and international), in-plant process control, and in-field measurements (environmental monitoring or safeguards). Our package's features, which address these applications, include the following: Small size for portability and ease of installation;battery or mains operation; a built-in battery to power the unit and a typical detector such as a small sample counter, for over 6 h if power lines are bad or noisy, if there is a temporary absence of power, or if portability is desired; complete support, including bias, for standard neutron detectors; a powerful communications package to easily facilitate robust external control over a serial port; and a C-library to simplify creating external control programs in computers or other controllers. Whereas the PSR specifically addresses the applications mentioned above, it also performs all the measurements made by previous electronics packages for neutron coincidence counters developed at Los Alamos and commercialized. The PSR electronics package, exclusive of carrying handle, is 8 by 10 by 20 cm; it contains the circuit boards, battery, and bias supply and weighs less than 2 kg. This instrument package is the second in an emerging family of portable measurement instruments being developed; the first was the Miniature and Modular Multichannel Analyzer (M[sup 3]CA). The PSR makes extensive use of hardware and software developed for the M[sup 3]CA; like the M[sup 3]CA, it is intended primarily for use with an external controller interfaced over a serial channel.

  3. Protein microchips : use for immunoassay and enzymatic reactions.

    SciTech Connect

    Arenkov, P.; Kukhtin, A.; Gemmell, A.; Voloschuk, S.; Chupeeva, V.; Mirzabekov, A.; Biochip Technology Center; Russian Academy of Sciences

    2000-02-15

    Different proteins such as antibodies, antigens, and enzymes were immobilized within the 100 x 100 x 20-{mu}m gel pads of protein microchips. A modified polyacrylamide gel has been developed to accommodate proteins of a size up to 400,000 daltons. Electrophoresis in the microchip reaction chamber speeded up antigen-antibody interactions within the gel. Protein microchips were used in immunoassays for detection of antigens or antibodies, as well as to carry out enzymatic reactions and to measure their kinetics in the absence or presence of an inhibitor. A protein microchip can be used several times in different immunoassays and enzymatic kinetic measurements.

  4. Comparison of digital rectal and microchip transponder thermometry in cats.

    PubMed

    Quimby, Jessica M; Olea-Popelka, Francisco; Lappin, Michael R

    2009-07-01

    This study compares the use of traditional rectal thermometry with an implantable microchip temperature transponder in cats. The microchip transponder was implanted over the shoulder blades and was programmed with cat identification information. Concurrently, the cats were involved in a study in which they were infected experimentally with feline herpesvirus 1; this situation enabled temperature comparisons in both normal and abnormal ranges. Results from the microchip transponder technique were compared with rectal thermometry by using a concordance test of agreement. These data revealed close agreement between rectal and microchip transponder thermometry in the cat at both normal and abnormal temperature ranges.

  5. Air-stable supported membranes for single-cell cytometry on PDMS microchips.

    PubMed

    Phillips, K Scott; Kang, Kyung Mo; Licata, Louise; Allbritton, Nancy L

    2010-04-01

    Protein-reinforced supported bilayer membranes (rSBMs) composed of phosphatidylcholine (PC), biotin-PE and Neutravidin were used to coat hybrid microchips composed of polydimethylsiloxane (PDMS) and glass. Since the coatings required a freshly oxidized, hydrophilic substrate, a novel method to rapidly connect reservoirs using plasma oxidation was first developed and found to support up to 5.2 N cm(-2) (1.5 N) pull-off force. rSBMs were then assembled in the oxidized hydrophilic channels. The electroosmotic mobility (mu(eo)) of rSBM-coated channels was measured over a 3 h time to evaluate the stability of the coatings for microchip electrophoresis. rSBM-coated microchips with a simple cross-design had excellent properties for microchip separations, yielding efficiencies of up to 700,000 plates m(-1) for fluorescent dyes and peptides. The separation performance of rSBM and PC-coated channels was evaluated after repeatedly drying and rehydrating the channels. The separation efficiency of fluorescein on PC-coated devices decreased by 40% after one dehydration cycle and nearly 75% after 3 cycles. In contrast for rSBM-coated devices there was no significant change in the fluorescein efficiency until the third cycle (10% decreased efficiency). rSBM-coated channels were also markedly more stable when placed in a dehydrated state during long-term storage compared to PC-coated channels, and showed reduced chip failure and no reduction in performance for up to one month of dehydrated storage. Finally, rSBM-coated devices were used to perform single-cell cytometry. Microchips that had been dehydrated, stored two weeks, and rehydrated prior to use demonstrated similar performance to newly coated devices for the separation of fluorescein and carboxyfluorescein from single cells. Thus rSBM-coated devices were rugged withstanding electric fields, prolonged storage under dehydrated conditions, and biofouling by cellular constituents while maintaining excellent separation

  6. Evaluation of a field-portable DNA microarray platform and nucleic acid amplification strategies for the detection of arboviruses, arthropods, and bloodmeals.

    PubMed

    Grubaugh, Nathan D; Petz, Lawrence N; Melanson, Vanessa R; McMenamy, Scott S; Turell, Michael J; Long, Lewis S; Pisarcik, Sarah E; Kengluecha, Ampornpan; Jaichapor, Boonsong; O'Guinn, Monica L; Lee, John S

    2013-02-01

    Highly multiplexed assays, such as microarrays, can benefit arbovirus surveillance by allowing researchers to screen for hundreds of targets at once. We evaluated amplification strategies and the practicality of a portable DNA microarray platform to analyze virus-infected mosquitoes. The prototype microarray design used here targeted the non-structural protein 5, ribosomal RNA, and cytochrome b genes for the detection of flaviviruses, mosquitoes, and bloodmeals, respectively. We identified 13 of 14 flaviviruses from virus inoculated mosquitoes and cultured cells. Additionally, we differentiated between four mosquito genera and eight whole blood samples. The microarray platform was field evaluated in Thailand and successfully identified flaviviruses (Culex flavivirus, dengue-3, and Japanese encephalitis viruses), differentiated between mosquito genera (Aedes, Armigeres, Culex, and Mansonia), and detected mammalian bloodmeals (human and dog). We showed that the microarray platform and amplification strategies described here can be used to discern specific information on a wide variety of viruses and their vectors.

  7. Evaluation of a Field-Portable DNA Microarray Platform and Nucleic Acid Amplification Strategies for the Detection of Arboviruses, Arthropods, and Bloodmeals

    PubMed Central

    Grubaugh, Nathan D.; Petz, Lawrence N.; Melanson, Vanessa R.; McMenamy, Scott S.; Turell, Michael J.; Long, Lewis S.; Pisarcik, Sarah E.; Kengluecha, Ampornpan; Jaichapor, Boonsong; O'Guinn, Monica L.; Lee, John S.

    2013-01-01

    Highly multiplexed assays, such as microarrays, can benefit arbovirus surveillance by allowing researchers to screen for hundreds of targets at once. We evaluated amplification strategies and the practicality of a portable DNA microarray platform to analyze virus-infected mosquitoes. The prototype microarray design used here targeted the non-structural protein 5, ribosomal RNA, and cytochrome b genes for the detection of flaviviruses, mosquitoes, and bloodmeals, respectively. We identified 13 of 14 flaviviruses from virus inoculated mosquitoes and cultured cells. Additionally, we differentiated between four mosquito genera and eight whole blood samples. The microarray platform was field evaluated in Thailand and successfully identified flaviviruses (Culex flavivirus, dengue-3, and Japanese encephalitis viruses), differentiated between mosquito genera (Aedes, Armigeres, Culex, and Mansonia), and detected mammalian bloodmeals (human and dog). We showed that the microarray platform and amplification strategies described here can be used to discern specific information on a wide variety of viruses and their vectors. PMID:23249687

  8. Nonlinear mode coupling in a microchip laser

    SciTech Connect

    Lacot, E.; Stoeckel, F.

    1996-09-01

    The dynamics of the total intensity and of each individual mode of a microchip laser have been studied. Because of the nonlinear mode coupling by spatial hole burning, the intensity fluctuation of each longitudinal mode can be described by {ital N} relaxation frequencies, where {ital N} is the number of lasing modes. Owing to the small cross-saturation coefficient between the longitudinal modes, the total intensity exhibits a behavior much more complex than the regular relaxation oscillations usually observed. As a result of the short photon lifetime of the microchip laser this unstable behavior of the total intensity can easily be observed even when the number of modes is small. For each longitudinal mode, we also observed beating and antiphase dynamics between two coupled states of orthogonal polarization. Numerical simulations permit a good description of the experimental results. {copyright} {ital 1996 Optical Society of America.}

  9. Detection of telomerase activity using microchip electrophoresis.

    PubMed

    Karasawa, Koji; Arakawa, Hidetoshi

    2015-07-01

    Telomerase participates in malignant transformation or immortalization of cells and thus has attracted attention as an anticancer drug target and diagnostic tumor marker. The telomeric repeat amplification protocol (TRAP) and improved TRAP methods (TRAP-fluorescence, TRAP-hybridization, etc.) are widely used forms of this telomerase assay. However, these approaches generally employ acrylamide gel electrophoresis after amplification of telomeric repeats by polymerase chain reaction (PCR), making these TRAP methods time consuming and technically demanding. In this study we developed a novel telomerase assay using microchip electrophoresis for rapid and highly sensitive detection of telomerase activity in cancer cells. The mixed gel of 0.8% hydroxypropyl methylcellulose (HPMC) and 0.3% polyethylene oxide (PEO) with SYBR Gold (fluorescent reagent) was used for microchip electrophoresis. As a result, the product amplified by a telomerase-positive cell could be measured in one cell per assay and detected with high reproducibility (CV=0.67%) in the short time of 100s.

  10. Fast high-throughput screening of H1N1 virus by parallel detection with multichannel microchip electrophoresis.

    PubMed

    Zhang, Peng; Nan, He; Lee, Seungah; Kang, Seong Ho

    2015-01-01

    Influenza is one of the acute respiratory diseases of human caused by the influenza A (H1N1) virus and accounted for major public health concerns worldwide. The polymerase chain reaction (PCR) methods are the most popular tools for clinical diagnosis of influenza A virus. Microchip electrophoresis is a widely used method for DNA molecules separation. Herein, we describe the fast and high-throughput separation of hemagglutinin (HA) and nucleocapsid protein (NP) gene PCR products (116 bp and 195 bp, respectively) by parallel detection with multichannel microchip electrophoresis and programmed step electric field strength (PSEFS). PMID:25673484

  11. Fast high-throughput screening of H1N1 virus by parallel detection with multichannel microchip electrophoresis.

    PubMed

    Zhang, Peng; Nan, He; Lee, Seungah; Kang, Seong Ho

    2015-01-01

    Influenza is one of the acute respiratory diseases of human caused by the influenza A (H1N1) virus and accounted for major public health concerns worldwide. The polymerase chain reaction (PCR) methods are the most popular tools for clinical diagnosis of influenza A virus. Microchip electrophoresis is a widely used method for DNA molecules separation. Herein, we describe the fast and high-throughput separation of hemagglutinin (HA) and nucleocapsid protein (NP) gene PCR products (116 bp and 195 bp, respectively) by parallel detection with multichannel microchip electrophoresis and programmed step electric field strength (PSEFS).

  12. Nanostructured optical microchips for cancer biomarker detection.

    PubMed

    Zhang, Tianhua; He, Yuan; Wei, Jianjun; Que, Long

    2012-01-01

    Herein we report the label-free detection of a cancer biomarker using newly developed arrayed nanostructured Fabry-Perot interferometer (FPI) microchips. Specifically, the prostate cancer biomarker free prostate-specific antigen (f-PSA) has been detected with a mouse anti-human PSA monoclonal antibody (mAb) as the receptor. Experiments found that the limit-of-detection of current nanostructured FPI microchip for f-PSA is about 10 pg/mL and the upper detection range for f-PSA can be dynamically changed by varying the amount of the PSA mAb immobilized on the sensing surface. The control experiments have also demonstrated that the immunoassay protocol used in the experiments shows excellent specificity and selectivity, suggesting the great potential to detect the cancer biomarkers at trace levels in complex biofluids. In addition, given its nature of low cost, simple-to-operation and batch fabrication capability, the arrayed nanostructured FPI microchip-based platform could provide an ideal technical tool for point-of-care diagnostics application and anticancer drug screen and discovery.

  13. Adjustable microchip ring trap for cold atoms and molecules

    SciTech Connect

    Baker, Paul M.; Stickney, James A.; Squires, Matthew B.; Scoville, James A.; Carlson, Evan J.; Buchwald, Walter R.; Miller, Steven M.

    2009-12-15

    We describe the design and function of a circular magnetic waveguide produced from wires on a microchip for atom interferometry using de Broglie waves. The guide is a two-dimensional magnetic minimum for trapping weak-field seeking states of atoms or molecules with a magnetic dipole moment. The design consists of seven circular wires sharing a common radius. We describe the design, the time-dependent currents of the wires and show that it is possible to form a circular waveguide with adjustable height and gradient while minimizing perturbation resulting from leads or wire crossings. This maximal area geometry is suited for rotation sensing with atom interferometry via the Sagnac effect using either cold atoms, molecules and Bose-condensed systems.

  14. Exploring the Integration of Field Portable Instrumentation into Real-Time Surface Science Operations with the RIS4E SSERVI Team

    NASA Astrophysics Data System (ADS)

    Young, K. E.; Bleacher, J. E.; Rogers, D.; Garry, W. B.; McAdam, A.; Scheidt, S. P.; Carter, L. M.; Glotch, T. D.

    2015-12-01

    The Remote, In Situ, and Synchrotron Studies for Science (RIS4E) team represents one node of the Solar System Exploration Research Virtual Institute (SSERVI) program. While the RIS4E team consists of four themes, each dedicated to a different aspect of airless body exploration, this submission details the RIS4E work underway to maximize an astronaut's effectiveness while conducting surface science. The next generation of surface science operations will look quite different than the EVAs (extravehicular activities) conducted during Apollo. Astronauts will possess data of much higher resolution than the Apollo reconnaissance data, and the EVAs will thus be designed to answer targeted science questions. Additionally, technological advancements over the last several decades have made it possible to conduct in situ analyses of a caliber much greater than was achievable during Apollo. For example, lab techniques such as x-ray fluorescence, x-ray diffraction, and multi-spectral imaging are now available in field portable formats, meaning that astronauts can gain real-time geochemical awareness during sample collection. The integration of these instruments into EVA operations, however, has not been widely tested. While these instruments will provide the astronaut with a high-resolution look at regional geochemistry and structure, their implementation could prove costly to the already constrained astronaut EVA timeline. The RIS4E team, through fieldwork at the December 1974 lava flow at Kilauea Volcano, HI, investigates the incorporation of portable technologies into planetary surface exploration and explores the relationship between science value added from these instruments and the cost associated with integrating them into an EVA timeline. We also consider what an appropriate instrumentation suite would be for the exploration of a volcanic terrain using this ideal terrestrial analog (see Rogers et al., Young et al., Bleacher et al., and Yant et al., this meeting).

  15. Ceeable Visual Field Analyzer (CVFA) for the portable, comprehensive, and tele-medical assessment of visual performance over time in warfighters, pilots, veterans, and civilians

    NASA Astrophysics Data System (ADS)

    Adams, Chris; Cerwin, John; Fink, Wolfgang

    2016-05-01

    We introduce a portable, easy-to-use, worldwide accessible (i.e., web-based), and comprehensive tele-medical visual performance assessment system - the Ceeable Visual Field Analyzer (CVFATM) - for warfighters, pilots, veterans, and civilians to: (1) Accurately and rapidly assess visual performance; (2) characterize visual performance and ocular conditions; and (3) detect the onset of ocular conditions to allow for timely countermeasures as well as patient follow-up over time. CVFA has been shown to be effective in multiple clinical studies. The technology is rapid (< 5 minutes per eye), easy (use of touchscreen), accurate (spatial resolution < 1 degree), non-invasive, and comprehensive. The system automatically characterizes visual field defects in real time to generate new diagnostic insight. The visual performance assessment system is readily adaptable to traditional clinical and non-clinical settings (e.g., in forward operating bases in the theatre). It is capable of rapidly assessing conditions affecting the visual performance of warfighters in the field, allowing for triage and timely application of therapeutic countermeasures. The enabling technologies are a low-cost tablet computer and Internet connection. Ceeable is deploying the technology on a global basis to patients who will benefit from monitoring changes in visual function.

  16. Development of a Portable Field Imaging Spectrometer: Application for the Identification of Sun-Dried and Sulfur-Fumigated Chinese Herbals.

    PubMed

    Zhang, Hongming; Wu, Taixia; Zhang, Lifu; Zhang, Peng

    2016-05-01

    We fabricated a visible-near-infrared (Vis-NIR) portable field imaging spectrometer with a prism-grating-prism element and a scanning mirror. The developed Vis-NIR imaging spectrometer, consisting of an INFINITY 3-1 detector and a V10E spectrometer from Specim Corporation, is designed to measure the spectral range between 0.4 and 1 µm with spectral resolution of 2-4 nm. In recent years, sulfur fumigation has been abused during the processing of certain freshly harvested Chinese herbs. Fourier transform infrared spectroscopy, fiber optic NIR spectrometry, and liquid chromatography-mass spectrometry are typically used to analyze the chemical profiles of sulfur-fumigated and sun-dried Chinese herbs. Field imaging spectrometry is rarely used to identify sulfur-fumigated herbs. In this study, field imaging spectrometry, principal component analysis, and the partial least squares-discriminant analysis multivariate data analysis method are used to distinguish sun-dried and sulfur-fumigated Chinese medicinal herbs with a sensitivity of 96.4% and a specificity of 98.3% for RPA identification. These results suggest that hyperspectral imaging is a potential technique to control medicine quality for medical applications.

  17. Chronic, programmed polypeptide delivery from an implanted, multireservoir microchip device.

    PubMed

    Prescott, James H; Lipka, Sara; Baldwin, Samuel; Sheppard, Norman F; Maloney, John M; Coppeta, Jonathan; Yomtov, Barry; Staples, Mark A; Santini, John T

    2006-04-01

    Implanted drug delivery systems are being increasingly used to realize the therapeutic potential of peptides and proteins. Here we describe the controlled pulsatile release of the polypeptide leuprolide from microchip implants over 6 months in dogs. Each microchip contains an array of discrete reservoirs from which dose delivery can be controlled by telemetry.

  18. Spontaneous Packaging and Hypothermic Storage of Mammalian Cells with a Cell-Membrane-Mimetic Polymer Hydrogel in a Microchip.

    PubMed

    Xu, Yan; Mawatari, Kazuma; Konno, Tomohiro; Kitamori, Takehiko; Ishihara, Kazuhiko

    2015-10-21

    Currently, continuous culture/passage and cryopreservation are two major, well-established methods to provide cultivated mammalian cells for experiments in laboratories. Due to the lack of flexibility, however, both laboratory-oriented methods are unable to meet the need for rapidly growing cell-based applications, which require cell supply in a variety of occasions outside of laboratories. Herein, we report spontaneous packaging and hypothermic storage of mammalian cells under refrigerated (4 °C) and ambient conditions (25 °C) using a cell-membrane-mimetic methacryloyloxyethyl phosphorylcholine (MPC) polymer hydrogel incorporated within a glass microchip. Its capability for hypothermic storage of cells was comparatively evaluated over 16 days. The results reveal that the cytocompatible MPC polymer hydrogel, in combination with the microchip structure, enabled hypothermic storage of cells with quite high viability, high intracellular esterase activity, maintained cell membrane integrity, and small morphological change for more than 1 week at 4 °C and at least 4 days at 25 °C. Furthermore, the stored cells could be released from the hydrogel and exhibited the ability to adhere to a surface and achieve confluence under standard cell culture conditions. Both hypothermic storage conditions are ordinary flexible conditions which can be easily established in places outside of laboratories. Therefore, cell packaging and storage using the hydrogel incorporated within the microchip would be a promising miniature and portable solution for flexible supply and delivery of small amounts of cells from bench to bedside.

  19. Spontaneous Packaging and Hypothermic Storage of Mammalian Cells with a Cell-Membrane-Mimetic Polymer Hydrogel in a Microchip.

    PubMed

    Xu, Yan; Mawatari, Kazuma; Konno, Tomohiro; Kitamori, Takehiko; Ishihara, Kazuhiko

    2015-10-21

    Currently, continuous culture/passage and cryopreservation are two major, well-established methods to provide cultivated mammalian cells for experiments in laboratories. Due to the lack of flexibility, however, both laboratory-oriented methods are unable to meet the need for rapidly growing cell-based applications, which require cell supply in a variety of occasions outside of laboratories. Herein, we report spontaneous packaging and hypothermic storage of mammalian cells under refrigerated (4 °C) and ambient conditions (25 °C) using a cell-membrane-mimetic methacryloyloxyethyl phosphorylcholine (MPC) polymer hydrogel incorporated within a glass microchip. Its capability for hypothermic storage of cells was comparatively evaluated over 16 days. The results reveal that the cytocompatible MPC polymer hydrogel, in combination with the microchip structure, enabled hypothermic storage of cells with quite high viability, high intracellular esterase activity, maintained cell membrane integrity, and small morphological change for more than 1 week at 4 °C and at least 4 days at 25 °C. Furthermore, the stored cells could be released from the hydrogel and exhibited the ability to adhere to a surface and achieve confluence under standard cell culture conditions. Both hypothermic storage conditions are ordinary flexible conditions which can be easily established in places outside of laboratories. Therefore, cell packaging and storage using the hydrogel incorporated within the microchip would be a promising miniature and portable solution for flexible supply and delivery of small amounts of cells from bench to bedside. PMID:26436637

  20. IATROGENIC MICROCHIP ARTERIAL EMBOLISM IN A CHILEAN FLAMINGO (PHOENICOPTERUS CHILENSIS).

    PubMed

    Olds, June E; Ewing, Jacob; Arruda, Paulo; Kuyper, Jennifer; Riedesel, Elizabeth; Miles, Kristina M

    2016-06-01

    Aberrant microchip migration has been reported in domestic animal species, but in most cases, this migration is atraumatic to the patient. Reports of microchip-associated trauma and sarcoma development also have been reported in a variety of mammal species. This report describes accidental arterial microchip insertion causing obstruction of the iliac artery in a Chilean flamingo (Phoenicopterus chilensis). Diagnostic imaging included digital radiography and pre- and post-contrast computed tomography to determine the location of the microchip. Surgical removal of the microchip was attempted; however, the flamingo died intraoperatively. Postmortem evaluation found trauma to the epicardium, without penetration of the ventricle. The descending aorta was found traumatized and identified as the most likely insertion point leading to the embolism.

  1. IATROGENIC MICROCHIP ARTERIAL EMBOLISM IN A CHILEAN FLAMINGO (PHOENICOPTERUS CHILENSIS).

    PubMed

    Olds, June E; Ewing, Jacob; Arruda, Paulo; Kuyper, Jennifer; Riedesel, Elizabeth; Miles, Kristina M

    2016-06-01

    Aberrant microchip migration has been reported in domestic animal species, but in most cases, this migration is atraumatic to the patient. Reports of microchip-associated trauma and sarcoma development also have been reported in a variety of mammal species. This report describes accidental arterial microchip insertion causing obstruction of the iliac artery in a Chilean flamingo (Phoenicopterus chilensis). Diagnostic imaging included digital radiography and pre- and post-contrast computed tomography to determine the location of the microchip. Surgical removal of the microchip was attempted; however, the flamingo died intraoperatively. Postmortem evaluation found trauma to the epicardium, without penetration of the ventricle. The descending aorta was found traumatized and identified as the most likely insertion point leading to the embolism. PMID:27468052

  2. Bulk modification of PDMS microchips by an amphiphilic copolymer.

    PubMed

    Xiao, Yan; Yu, Xiao-Dong; Xu, Jing-Juan; Chen, Hong-Yuan

    2007-09-01

    A simple and rapid bulk-modification method based on adding an amphiphilic copolymer during the fabrication process was employed to modify PDMS microchips. Poly(lactic acid)-poly(ethylene glycol) (PLA-PEG) was used as the additive substance. Compared to the native PDMS microchips, both the contact angle and the EOF of the bulk-modified PDMS microchips decreased. The effects of the additive loading and the pH on the EOF were investigated in detail. The bulk-modified PDMS microchips exhibited reproducible and stable EOF behavior. The application of the bulk-modified PDMS microchips was also studied and the results indicated that they could be successfully used to separate amino acids and to suppress protein adsorption.

  3. Portable Technology Comes of Age

    ERIC Educational Resources Information Center

    Wangemann, Paul; Lewis, Nina; Squires, David A.

    2003-01-01

    The PDA was originally conceived of as a portable handheld electronic device that provided a user with a tool to organize his or her life through easy access to a personal calendar, daily planner, and address book. Over the years, these devices have expanded to include many new functions, which have helped more applications in diverse fields. This…

  4. Experiences with Hermann's tortoise (Testudo hermanni) microchipping in Slovenia - Short communication.

    PubMed

    Dovč, Alenka; Stvarnik, Mateja; Mavri, Urška; Gregurić-Gračner, Gordana; Tomažić, Iztok

    2016-03-01

    This study describes experiences obtained with microchipping of Hermann's tortoises in Slovenia. Over a period of three years, a total of 5,128 Hermann's tortoises from parental breeding stock were microchipped. Microchips were implanted subcutaneously in the left inguinal region. During the application of microchips, males were bleeding in 2.6% and females in 1.4% of the cases. Bleeding frequency was related to sex, animal size and environmental temperature at the time of microchipping. The presence of microchips was followed up over a period of several years. At the control check conducted a few years later, all previously microchipped tortoises were included. Out of the entire parental breeding stock, 235 (4.6%) had lost their microchips, thus 63 males (5.7%) and 172 females (4.3%) were unmarked. The possible reasons for microchip loss are migration or inactivity of the implanted microchips. PMID:26919141

  5. [Microchips based on three dimensional gel cells: history and perspective].

    PubMed

    Kolchinskiĭ, A M; Griadunov, D A; Lysov, Iu P; Mikhaĭlovich, V M; Nasedkina, T V; Turygin, A Iu; Rubina, A Iu; Barskiĭ, V E; Zasedatelev, A S

    2004-01-01

    The review describes the history of creation and development of the microchip technology and its role in the human genome project in Russia. The emphasis is placed on the three-dimensional gel-based microchips developed at the Center of Biological Microchips headed by A.D. Mirzabekov since 1988. The gel-based chips of the last generation, IMAGE chips (Immobilized Micro Array of Gel Elements), have a number of advantages over the previous versions. The microchips are manufactured by photo-initiated copolymerization of gel components and immobilized molecules (DNA, proteins, and ligands). This ensures an even distribution of the immobilized probe throughout the microchip gel element with a high yield (about 50% for oligonucleotides). The use of methacrylamide as a main component of the polymerization mixture resulted in a substantial increase of gel porosity without affecting its mechanical strength and stability, which allowed one to work with the DNA fragments of up to 500 nt in length, as well as with rather large protein molecules. At present, the gel-based microchips are widely applied to address different problems. The generic microchips containing a complete set of possible hexanucleotides are used to reveal the DNA motifs binding with different proteins and to study the DNA-protein interactions. The oligonucleotide microchips are a cheap and reliable tool of diagnostics designed for mass application. Biochips have been developed for identification of the tuberculosis pathogen and its antibiotic-resistant forms; for diagnostics of orthopoxviruses, including the smallpox virus; for diagnostics of the anthrax pathogen; and for identification of chromosomal rearrangements in leukemia patients. The protein microchips can be adapted for further use in proteomics. Bacterial and yeast cells were also immobilized in the gel, maintaining their viability, which open a wide potential for creation biosensors on the basis of microchips.

  6. Low-power microwave-mediated heating for microchip-based PCR.

    PubMed

    Marchiarullo, Daniel J; Sklavounos, Angelique H; Oh, Kyudam; Poe, Brian L; Barker, N Scott; Landers, James P

    2013-09-01

    Microwave energy has been used to rapidly heat food and drinks for decades, in addition to assisting other chemical reactions. However, only recently has microwave energy been applied in microfluidic systems to heat solution in reaction chambers, in particular, the polymerase chain reaction (PCR). One of the difficulties in developing microwave-mediated heating on a microchip is the construction of the appropriate architecture for delivery of the energy to specific micro-areas on the microchip. This work employs commercially-available microwave components commonly used in the wireless communications industry to generate a microwave signal, and a microstrip transmission line to deliver the energy to a 1 μL reaction chamber fabricated in plastic microdevices. A model was developed to create transmission lines that would optimally transmit energy to the reaction chamber at a given frequency, minimizing energy usage while focusing microwave delivery to the target chamber. Two different temperature control methods were demonstrated, varying microwave power or frequency. This system was used to amplify a fragment of the lambda-phage genome, thereby demonstrating its potential for integration into a portable PCR system.

  7. Low-power microwave-mediated heating for microchip-based PCR.

    PubMed

    Marchiarullo, Daniel J; Sklavounos, Angelique H; Oh, Kyudam; Poe, Brian L; Barker, N Scott; Landers, James P

    2013-09-01

    Microwave energy has been used to rapidly heat food and drinks for decades, in addition to assisting other chemical reactions. However, only recently has microwave energy been applied in microfluidic systems to heat solution in reaction chambers, in particular, the polymerase chain reaction (PCR). One of the difficulties in developing microwave-mediated heating on a microchip is the construction of the appropriate architecture for delivery of the energy to specific micro-areas on the microchip. This work employs commercially-available microwave components commonly used in the wireless communications industry to generate a microwave signal, and a microstrip transmission line to deliver the energy to a 1 μL reaction chamber fabricated in plastic microdevices. A model was developed to create transmission lines that would optimally transmit energy to the reaction chamber at a given frequency, minimizing energy usage while focusing microwave delivery to the target chamber. Two different temperature control methods were demonstrated, varying microwave power or frequency. This system was used to amplify a fragment of the lambda-phage genome, thereby demonstrating its potential for integration into a portable PCR system. PMID:23843031

  8. Quantification of trace arsenic in soils by field-portable X-ray fluorescence spectrometry: considerations for sample preparation and measurement conditions.

    PubMed

    Parsons, Chris; Margui Grabulosa, Eva; Pili, Eric; Floor, Geerke H; Roman-Ross, Gabriela; Charlet, Laurent

    2013-11-15

    Recent technological improvements have led to the widespread adoption of field portable energy dispersive X-ray fluorescence (FP-XRF) by governmental agencies, environmental consultancies and research institutions. FP-XRF units often include analysis modes specifically designed for the quantification of trace elements in soils. Using these modes, X-ray tube based FP-XRF units can offer almost "point and shoot" ease of use and results comparable to those of laboratory based instruments. Nevertheless, FP-XRF analysis is sensitive to spectral interferences as well as physical and chemical matrix effects which can result in decreased precision and accuracy. In this study, an X-ray tube-based FP-XRF analyser was used to determine trace (low ppm) concentrations of As in a floodplain soil. The effect of different sample preparation and analysis conditions on precision and accuracy were systematically evaluated. We propose strategies to minimise sources of error and maximise data precision and accuracy, achieving in situ limits of detection and precision of 6.8 ppm and 14.4%RSD, respectively for arsenic. We demonstrate that soil moisture, even in relatively dry soils, dramatically affects analytical performance with a signal loss of 37% recorded for arsenic at 20 wt% soil moisture relative to dry soil. We also highlight the importance of the use of certified reference materials and independent measurement methods to ensure accurate correction of field values.

  9. A portable x-ray source with a nanostructured Pt-coated silicon field emission cathode for absorption imaging of low-Z materials

    NASA Astrophysics Data System (ADS)

    Basu, Anirban; Swanwick, Michael E.; Fomani, Arash A.; Velásquez-García, Luis Fernando

    2015-06-01

    We report the design, fabrication, and characterization of a portable x-ray generator for imaging of low-atomic number materials such as biological soft tissue. The system uses a self-aligned, gated, Pt-coated silicon field emitter cathode with two arrays of 62 500 nano-sharp tips arranged in a square grid with 10 μm emitter pitch, and a natural convection-cooled reflection anode composed of a Cu bar coated with a thin Mo film. Characterization of the field emitter array demonstrated continuous emission of 1 mA electron current (16 mA cm  -  2) with  >95% current transmission at a 150 V gate-emitter bias voltage for over 20 h with no degradation. The emission of the x-ray source was characterized across a range of anode bias voltages to maximize the fraction of photons from the characteristic K-shell peaks of the Mo film to produce a quasi-monochromatic photon beam, which enables capturing high-contrast images of low-atomic number materials. The x-ray source operating at the optimum anode bias voltage, i.e. 35 kV, was used to image ex vivo and nonorganic samples in x-ray fluoroscopic mode while varying the tube current; the images resolve feature sizes as small as ~160 µm.

  10. Portable MRI

    SciTech Connect

    Espy, Michelle A.

    2012-06-29

    This project proposes to: (1) provide the power of MRI to situations where it presently isn't available; (2) perform the engineering required to move from lab to a functional prototype; and (3) leverage significant existing infrastructure and capability in ultra-low field MRI. The reasons for doing this: (1) MRI is the most powerful tool for imaging soft-tissue (e.g. brain); (2) Billions don't have access due to cost or safety issues; (3) metal will heat/move in high magnetic fields; (4) Millions of cases of traumatic brain injury in US alone; (5) even more of non-traumatic brain injury; (6) (e.g. stroke, infection, chemical exposure); (7) Need for early diagnostic; (8) 'Signature' wound of recent conflicts; (9) 22% of injuries; (10) Implications for post-traumatic stress disorder; and (11) chronic traumatic encephalopathy.

  11. Stand-Sit Microchip for High-Throughput, Multiplexed Analysis of Single Cancer Cells.

    PubMed

    Ramirez, Lisa; Herschkowitz, Jason I; Wang, Jun

    2016-01-01

    Cellular heterogeneity in function and response to therapeutics has been a major challenge in cancer treatment. The complex nature of tumor systems calls for the development of advanced multiplexed single-cell tools that can address the heterogeneity issue. However, to date such tools are only available in a laboratory setting and don't have the portability to meet the needs in point-of-care cancer diagnostics. Towards that application, we have developed a portable single-cell system that is comprised of a microchip and an adjustable clamp, so on-chip operation only needs pipetting and adjusting of clamping force. Up to 10 proteins can be quantitated from each cell with hundreds of single-cell assays performed in parallel from one chip operation. We validated the technology and analyzed the oncogenic signatures of cancer stem cells by quantitating both aldehyde dehydrogenase (ALDH) activities and 5 signaling proteins in single MDA-MB-231 breast cancer cells. The technology has also been used to investigate the PI3K pathway activities of brain cancer cells expressing mutant epidermal growth factor receptor (EGFR) after drug intervention targeting EGFR signaling. Our portable single-cell system will potentially have broad application in the preclinical and clinical settings for cancer diagnosis in the future. PMID:27581736

  12. Stand-Sit Microchip for High-Throughput, Multiplexed Analysis of Single Cancer Cells.

    PubMed

    Ramirez, Lisa; Herschkowitz, Jason I; Wang, Jun

    2016-01-01

    Cellular heterogeneity in function and response to therapeutics has been a major challenge in cancer treatment. The complex nature of tumor systems calls for the development of advanced multiplexed single-cell tools that can address the heterogeneity issue. However, to date such tools are only available in a laboratory setting and don't have the portability to meet the needs in point-of-care cancer diagnostics. Towards that application, we have developed a portable single-cell system that is comprised of a microchip and an adjustable clamp, so on-chip operation only needs pipetting and adjusting of clamping force. Up to 10 proteins can be quantitated from each cell with hundreds of single-cell assays performed in parallel from one chip operation. We validated the technology and analyzed the oncogenic signatures of cancer stem cells by quantitating both aldehyde dehydrogenase (ALDH) activities and 5 signaling proteins in single MDA-MB-231 breast cancer cells. The technology has also been used to investigate the PI3K pathway activities of brain cancer cells expressing mutant epidermal growth factor receptor (EGFR) after drug intervention targeting EGFR signaling. Our portable single-cell system will potentially have broad application in the preclinical and clinical settings for cancer diagnosis in the future.

  13. Stand-Sit Microchip for High-Throughput, Multiplexed Analysis of Single Cancer Cells

    PubMed Central

    Ramirez, Lisa; Herschkowitz, Jason I.; Wang, Jun

    2016-01-01

    Cellular heterogeneity in function and response to therapeutics has been a major challenge in cancer treatment. The complex nature of tumor systems calls for the development of advanced multiplexed single-cell tools that can address the heterogeneity issue. However, to date such tools are only available in a laboratory setting and don’t have the portability to meet the needs in point-of-care cancer diagnostics. Towards that application, we have developed a portable single-cell system that is comprised of a microchip and an adjustable clamp, so on-chip operation only needs pipetting and adjusting of clamping force. Up to 10 proteins can be quantitated from each cell with hundreds of single-cell assays performed in parallel from one chip operation. We validated the technology and analyzed the oncogenic signatures of cancer stem cells by quantitating both aldehyde dehydrogenase (ALDH) activities and 5 signaling proteins in single MDA-MB-231 breast cancer cells. The technology has also been used to investigate the PI3K pathway activities of brain cancer cells expressing mutant epidermal growth factor receptor (EGFR) after drug intervention targeting EGFR signaling. Our portable single-cell system will potentially have broad application in the preclinical and clinical settings for cancer diagnosis in the future. PMID:27581736

  14. Using microchip gel electrophoresis to probe DNA-drug binding interactions.

    PubMed

    Shi, Nan; Ugaz, Victor M

    2014-01-01

    Binding of small molecules with DNA plays an important role in many biological functions such as DNA replication, repair, and transcription. These interactions also offer enormous potential as targets for diagnostics and therapeutics, leading to intense interest in development of methods to probe the underlying binding events. In this chapter, we present a new approach to investigate the structural changes that accompany binding of DNA and small molecules. Instead of relying on conventional yet delicate single-molecule imaging methods, we show how a single microchip gel electrophoresis experiment incorporating both constant electric field and on-off actuation over a specific frequency range enables fundamental structural parameters (e.g., contour and persistence lengths) to be simultaneously determined. The microchip format offers an attractive combination of simplicity and scale-up potential that makes it amenable for high-throughput screening. PMID:24162976

  15. Present state of microchip electrophoresis: state of the art and routine applications.

    PubMed

    Castro, Eric R; Manz, Andreas

    2015-02-20

    Microchip electrophoresis (MCE) was one of the earliest applications of the micro-total analysis system (μ-TAS) concept, whose aim is to reduce analysis time and reagent and sample consumption while increasing throughput and portability by miniaturizing analytical laboratory procedures onto a microfluidic chip. More than two decades on, electrophoresis remains the most common separation technique used in microfluidic applications. MCE-based instruments have had some commercial success and have found application in many disciplines. This review will consider the present state of MCE including recent advances in technology and both novel and routine applications in the laboratory. We will also attempt to assess the impact of MCE in the scientific community and its prospects for the future.

  16. Photopatterning of Hydrogel Microarrays in Closed Microchips.

    PubMed

    Gumuscu, Burcu; Bomer, Johan G; van den Berg, Albert; Eijkel, Jan C T

    2015-12-14

    To date, optical lithography has been extensively used for in situ patterning of hydrogel structures in a scale range from hundreds of microns to a few millimeters. The two main limitations which prevent smaller feature sizes of hydrogel structures are (1) the upper glass layer of a microchip maintains a large spacing (typically 525 μm) between the photomask and hydrogel precursor, leading to diffraction of UV light at the edges of mask patterns, (2) diffusion of free radicals and monomers results in irregular polymerization near the illumination interface. In this work, we present a simple approach to enable the use of optical lithography to fabricate hydrogel arrays with a minimum feature size of 4 μm inside closed microchips. To achieve this, we combined two different techniques. First, the upper glass layer of the microchip was thinned by mechanical polishing to reduce the spacing between the photomask and hydrogel precursor, and thereby the diffraction of UV light at the edges of mask patterns. The polishing process reduces the upper layer thickness from ∼525 to ∼100 μm, and the mean surface roughness from 20 to 3 nm. Second, we developed an intermittent illumination technique consisting of short illumination periods followed by relatively longer dark periods, which decrease the diffusion of monomers. Combination of these two methods allows for fabrication of 0.4 × 10(6) sub-10 μm sized hydrogel patterns over large areas (cm(2)) with high reproducibility (∼98.5% patterning success). The patterning method is tested with two different types of photopolymerizing hydrogels: polyacrylamide and polyethylene glycol diacrylate. This method enables in situ fabrication of well-defined hydrogel patterns and presents a simple approach to fabricate 3-D hydrogel matrices for biomolecule separation, biosensing, tissue engineering, and immobilized protein microarray applications.

  17. Photopatterning of Hydrogel Microarrays in Closed Microchips.

    PubMed

    Gumuscu, Burcu; Bomer, Johan G; van den Berg, Albert; Eijkel, Jan C T

    2015-12-14

    To date, optical lithography has been extensively used for in situ patterning of hydrogel structures in a scale range from hundreds of microns to a few millimeters. The two main limitations which prevent smaller feature sizes of hydrogel structures are (1) the upper glass layer of a microchip maintains a large spacing (typically 525 μm) between the photomask and hydrogel precursor, leading to diffraction of UV light at the edges of mask patterns, (2) diffusion of free radicals and monomers results in irregular polymerization near the illumination interface. In this work, we present a simple approach to enable the use of optical lithography to fabricate hydrogel arrays with a minimum feature size of 4 μm inside closed microchips. To achieve this, we combined two different techniques. First, the upper glass layer of the microchip was thinned by mechanical polishing to reduce the spacing between the photomask and hydrogel precursor, and thereby the diffraction of UV light at the edges of mask patterns. The polishing process reduces the upper layer thickness from ∼525 to ∼100 μm, and the mean surface roughness from 20 to 3 nm. Second, we developed an intermittent illumination technique consisting of short illumination periods followed by relatively longer dark periods, which decrease the diffusion of monomers. Combination of these two methods allows for fabrication of 0.4 × 10(6) sub-10 μm sized hydrogel patterns over large areas (cm(2)) with high reproducibility (∼98.5% patterning success). The patterning method is tested with two different types of photopolymerizing hydrogels: polyacrylamide and polyethylene glycol diacrylate. This method enables in situ fabrication of well-defined hydrogel patterns and presents a simple approach to fabricate 3-D hydrogel matrices for biomolecule separation, biosensing, tissue engineering, and immobilized protein microarray applications. PMID:26558488

  18. Portable waveguide display system with a large field of view by integrating freeform elements and volume holograms

    PubMed Central

    Han, Jian; Liu, Juan; Yao, Xincheng; Wang, Yongtian

    2015-01-01

    A compact waveguide display system integrating freeform elements and volume holograms is presented here for the first time. The use of freeform elements can broaden the field of view, which limits the applications of a holographic waveguide. An optimized system can achieve a diagonal field of view of 45° when the thickness of the waveguide planar is 3mm. Freeform-elements in-coupler and the volume holograms out-coupler were designed in detail in our study, and the influence of grating configurations on diffraction efficiency was analyzed thoroughly. The off-axis aberrations were well compensated by the in-coupler and the diffraction efficiency of the optimized waveguide display system could reach 87.57%. With integrated design, stability and reliability of this monochromatic display system were achieved and the alignment of the system was easily controlled by the record of the volume holograms, which makes mass production possible. PMID:25836207

  19. Parallel thermodynamic analysis of duplexes on oligodeoxyribonucleotide microchips.

    SciTech Connect

    Fotin, A. V.; Drobyshev, A. L.; Proudnikov, D. Y.; Perov, A. N.; Mirzabekov, A. D.; Center for Mechanistic Biology and Biotechnology; Engelhardt Inst. of Molecular Biology

    1998-03-15

    A microchip method has been developed for massive and parallel thermodynamic analyses of DNA duplexes. Fluorescently labeled oligonucleotides were hybridized with oligonucleotides immobilized in the 100 x 100 x 20 mum gel pads of the microchips. The equilibrium melting curves for all microchip duplexes were measured in real time in parallel for all microchip duplexes. Thermodynamic data for perfect and mismatched duplexes that were obtained using the microchip method directly correlated with data obtained in solution. Fluorescent labels or longer linkers between the gel and the oligonucleotides appeared to have no significant effect on duplex stability. Extending the immobilized oligonucleotides with a four-base mixture from the 3'-end or one or two universal bases (5-nitroindole) from the 3'- and/or 5'- end increased the stabilities of their duplexes. These extensions were applied to increase the stabilities of the duplexes formed with short oligonucleotides in microchips, to significantly lessen the differences in melting curves of the AT- and GC-rich duplexes, and to improve discrimination of perfect duplexes from those containing poorly recognized terminal mismatches. This study explored a way to increase the efficiency of sequencing by hybridization on oligonucleotide microchips.

  20. Readability and histological biocompatibility of microchip transponders in horses.

    PubMed

    Wulf, M; Wohlsein, P; Aurich, J E; Nees, M; Baumgärtner, W; Aurich, C

    2013-10-01

    Identification of horses by microchip transponder is mandatory within the European Union with only a few exceptions. In this study, the readability of such microchips in 428 horses with three different scanners (A, B and C) and the histological changes at the implantation site in 16 animals were assessed. Identification of microchips differed between scanners (P<0.001), and with 'side of neck' (P<0.001). Scanners A, B and C identified 93.5%, 89.7% and 100% of microchips, respectively, on the 'chip-bearing' side of the neck. From the contralateral side, scanners A, B and C identified 21.5%, 26.9% and 89.5% of transponders, respectively. Microchip readability was affected by age (P<0.001), but not by breed of horse. At necropsy, transponders were found in the subcutaneous fat (n=3), inter- or peri-muscular connective tissue (n=8), or musculature (n=5), where they were surrounded by a fibrous capsule ranging in thickness from 12.7 to 289.5 μm in 15 animals. In two animals, immature granulation tissue with attendant granulomatous inflammation, and a granulomatous myositis, surrounding the microchip were identified, respectively. Severe (n=1), moderate (n=1), and mild (n=3) lymphohistiocytic inflammation was noted within the fibrous capsule. Microchip transponders were found to be a highly reliable and biocompatible method of horse identification. PMID:23769456

  1. Portable Device Measures Perpendicularity Of Threaded Hole

    NASA Technical Reports Server (NTRS)

    Scarpelli, August R.; Buttler, Daniel W.

    1995-01-01

    Simple portable device gives quantitative information on amount by which axis of threaded hole in workpiece deviates from perpendicularity to adjacent exterior surface of workpiece. Measurements made easily in factory, shop, or field.

  2. A Field-Portable Membrane Introduction Mass Spectrometer for Real-time Quantitation and Spatial Mapping of Atmospheric and Aqueous Contaminants

    NASA Astrophysics Data System (ADS)

    Bell, Ryan J.; Davey, Nicholas G.; Martinsen, Morten; Collin-Hansen, Christian; Krogh, Erik T.; Gill, Christopher G.

    2015-02-01

    Environmental concentrations of volatile and semivolatile organic compounds (VOC/SVOCs) can vary dramatically in time and space under the influence of environmental conditions. In an industrial setting, multiple point and diffuse sources can contribute to fugitive emissions. Assessments and monitoring programs using periodic grab sampling provide limited information, often with delay times of days or weeks. We report the development and use of a novel, portable membrane introduction mass spectrometry (MIMS) system capable of resolving and quantifying VOC and SVOCs with high spatial and temporal resolution, in the field, in real-time. An electron impact ionization cylindrical ion trap mass spectrometer modified with a capillary hollow fiber polydimethylsiloxane membrane interface was used for continuous air and water sampling. Tandem mass spectrometry and selected ion monitoring scans performed in series allowed for the quantitation of target analytes, and full scan mode was used to survey for unexpected analytes. Predeployment and in-field external calibrations were combined with a continuously infused internal standard to enable real-time quantitation and monitor instrument performance. The system was operated in a moving vehicle with internet-linked data processing and storage. Software development to integrate MIMS and relevant meta-data for visualization and geospatial presentation in Google Earth is presented. Continuous quantitation enables the capture of transient events that may be missed or under-represented by traditional grab sampling strategies. Real-time geospatial maps of chemical concentration enable adaptive sampling and in-field decision support. Sample datasets presented in this work were collected in Northern Alberta in 2010-2012.

  3. A field-portable membrane introduction mass spectrometer for real-time quantitation and spatial mapping of atmospheric and aqueous contaminants.

    PubMed

    Bell, Ryan J; Davey, Nicholas G; Martinsen, Morten; Collin-Hansen, Christian; Krogh, Erik T; Gill, Christopher G

    2015-02-01

    Environmental concentrations of volatile and semivolatile organic compounds (VOC/SVOCs) can vary dramatically in time and space under the influence of environmental conditions. In an industrial setting, multiple point and diffuse sources can contribute to fugitive emissions. Assessments and monitoring programs using periodic grab sampling provide limited information, often with delay times of days or weeks. We report the development and use of a novel, portable membrane introduction mass spectrometry (MIMS) system capable of resolving and quantifying VOC and SVOCs with high spatial and temporal resolution, in the field, in real-time. An electron impact ionization cylindrical ion trap mass spectrometer modified with a capillary hollow fiber polydimethylsiloxane membrane interface was used for continuous air and water sampling. Tandem mass spectrometry and selected ion monitoring scans performed in series allowed for the quantitation of target analytes, and full scan mode was used to survey for unexpected analytes. Predeployment and in-field external calibrations were combined with a continuously infused internal standard to enable real-time quantitation and monitor instrument performance. The system was operated in a moving vehicle with internet-linked data processing and storage. Software development to integrate MIMS and relevant meta-data for visualization and geospatial presentation in Google Earth is presented. Continuous quantitation enables the capture of transient events that may be missed or under-represented by traditional grab sampling strategies. Real-time geospatial maps of chemical concentration enable adaptive sampling and in-field decision support. Sample datasets presented in this work were collected in Northern Alberta in 2010-2012.

  4. A field-portable membrane introduction mass spectrometer for real-time quantitation and spatial mapping of atmospheric and aqueous contaminants.

    PubMed

    Bell, Ryan J; Davey, Nicholas G; Martinsen, Morten; Collin-Hansen, Christian; Krogh, Erik T; Gill, Christopher G

    2015-02-01

    Environmental concentrations of volatile and semivolatile organic compounds (VOC/SVOCs) can vary dramatically in time and space under the influence of environmental conditions. In an industrial setting, multiple point and diffuse sources can contribute to fugitive emissions. Assessments and monitoring programs using periodic grab sampling provide limited information, often with delay times of days or weeks. We report the development and use of a novel, portable membrane introduction mass spectrometry (MIMS) system capable of resolving and quantifying VOC and SVOCs with high spatial and temporal resolution, in the field, in real-time. An electron impact ionization cylindrical ion trap mass spectrometer modified with a capillary hollow fiber polydimethylsiloxane membrane interface was used for continuous air and water sampling. Tandem mass spectrometry and selected ion monitoring scans performed in series allowed for the quantitation of target analytes, and full scan mode was used to survey for unexpected analytes. Predeployment and in-field external calibrations were combined with a continuously infused internal standard to enable real-time quantitation and monitor instrument performance. The system was operated in a moving vehicle with internet-linked data processing and storage. Software development to integrate MIMS and relevant meta-data for visualization and geospatial presentation in Google Earth is presented. Continuous quantitation enables the capture of transient events that may be missed or under-represented by traditional grab sampling strategies. Real-time geospatial maps of chemical concentration enable adaptive sampling and in-field decision support. Sample datasets presented in this work were collected in Northern Alberta in 2010-2012. PMID:25477082

  5. Laboratory evaluation of a field-portable sealed source X-ray fluorescence spectrometer for determination of metals in air filter samples.

    PubMed

    Lawryk, Nicholas J; Feng, H Amy; Chen, Bean T

    2009-07-01

    Recent advances in field-portable X-ray fluorescence (FP XRF) spectrometer technology have made it a potentially valuable screening tool for the industrial hygienist to estimate worker exposures to airborne metals. Although recent studies have shown that FP XRF technology may be better suited for qualitative or semiquantitative analysis of airborne lead in the workplace, these studies have not extensively addressed its ability to measure other elements. This study involved a laboratory-based evaluation of a representative model FP XRF spectrometer to measure elements commonly encountered in workplace settings that may be collected on air sample filter media, including chromium, copper, iron, manganese, nickel, lead, and zinc. The evaluation included assessments of (1) response intensity with respect to location on the probe window, (2) limits of detection for five different filter media, (3) limits of detection as a function of analysis time, and (4) bias, precision, and accuracy estimates. Teflon, polyvinyl chloride, polypropylene, and mixed cellulose ester filter media all had similarly low limits of detection for the set of elements examined. Limits of detection, bias, and precision generally improved with increasing analysis time. Bias, precision, and accuracy estimates generally improved with increasing element concentration. Accuracy estimates met the National Institute for Occupational Safety and Health criterion for nearly all the element and concentration combinations. Based on these results, FP XRF spectrometry shows potential to be useful in the assessment of worker inhalation exposures to other metals in addition to lead. PMID:19387888

  6. Comparison of field portable measurements of ultrafine TiO2: X-ray fluorescence, laser-induced breakdown spectroscopy, and Fourier-transform infrared spectroscopy

    PubMed Central

    Miller, Arthur L.; Stipe, Christopher; Brown, Jonathan; Murphy, Nate; Stefaniak, Aleksandr B.

    2016-01-01

    Laboratory measurements of ultrafin0e titanium dioxide (TiO2) particulate matter loaded on filters were made using three field portable methods (X-ray fluorescence (XRF), laser-induced breakdown spectroscopy (LIBS), and Fourier-transform infrared (FTIR) spectroscopy) to assess their potential for determining end-of-shift exposure. Ultrafine TiO2 particles were aerosolized and collected onto 37 mm polycarbonate track-etched (PCTE) filters in the range of 3 to 578 µg titanium (Ti). Limit of detection (LOD), limit of quantification (LOQ), and calibration fit were determined for each measurement method. The LOD's were 11.8, 0.032, and 108 µg Ti per filter, for XRF, LIBS, and FTIR, respectively and the LOQ's were 39.2, 0.11, and 361 µg Ti per filter, respectively. The XRF calibration curve was linear over the widest dynamic range, up to the maximum loading tested (578 µg Ti per filter). LIBS was more sensitive but, due to the sample preparation method, the highest loaded filter measurable was 252 µg Ti per filter. XRF and LIBS had good predictability measured by regressing the predicted mass to the gravimetric mass on the filter. XRF and LIBS produced overestimations of 4% and 2%, respectively, with coefficients of determination (R2) of 0.995 and 0.998. FTIR measurements were less dependable due to interference from the PCTE filter media and overestimated mass by 2% with an R2 of 0.831. PMID:23632878

  7. Laboratory evaluation of a field-portable sealed source X-ray fluorescence spectrometer for determination of metals in air filter samples.

    PubMed

    Lawryk, Nicholas J; Feng, H Amy; Chen, Bean T

    2009-07-01

    Recent advances in field-portable X-ray fluorescence (FP XRF) spectrometer technology have made it a potentially valuable screening tool for the industrial hygienist to estimate worker exposures to airborne metals. Although recent studies have shown that FP XRF technology may be better suited for qualitative or semiquantitative analysis of airborne lead in the workplace, these studies have not extensively addressed its ability to measure other elements. This study involved a laboratory-based evaluation of a representative model FP XRF spectrometer to measure elements commonly encountered in workplace settings that may be collected on air sample filter media, including chromium, copper, iron, manganese, nickel, lead, and zinc. The evaluation included assessments of (1) response intensity with respect to location on the probe window, (2) limits of detection for five different filter media, (3) limits of detection as a function of analysis time, and (4) bias, precision, and accuracy estimates. Teflon, polyvinyl chloride, polypropylene, and mixed cellulose ester filter media all had similarly low limits of detection for the set of elements examined. Limits of detection, bias, and precision generally improved with increasing analysis time. Bias, precision, and accuracy estimates generally improved with increasing element concentration. Accuracy estimates met the National Institute for Occupational Safety and Health criterion for nearly all the element and concentration combinations. Based on these results, FP XRF spectrometry shows potential to be useful in the assessment of worker inhalation exposures to other metals in addition to lead.

  8. Generating electrospray from microchip devices using electroosmotic pumping

    SciTech Connect

    Ramsey, R.S.; Ramsey, J.M.

    1997-03-15

    A method of generating electrospray from solutions emerging from small channels etched on planer substrates in described. The fluids are delivered using electroosmotically induced pressures and are sprayed electrostatically from the terminus of a channel by applying an electrical potential of sufficient amplitude to generate the electrospray between the microchip and a conductor spaced from the channel terminus. No major modification of the microchip is required other than to expose a channel opening. The principles that regulate the fluid delivery are described and demonstrated. A spectrum for a test compound, tetrabutylammonium iodide, that was continuously electrophoresed was obtained by coupling the microchip to an ion trap mass spectrometer. 35 refs., 6 figs.

  9. A graphene-modified cellulose paper microchip for HIV detection

    NASA Astrophysics Data System (ADS)

    Safavieh, Mohammadali; Khetani, Sultan; Kaul, Vivasvat; Kuritzkes, Daniel R.; Shafiee, Hadi

    2015-05-01

    Rapid and inexpensive virus detection and quantification at the point-of-care is of paramount importance for HIV management in resource-limited settings. Here, we report on an easy-to-fabricate, cellulose paper-based microchip with printed graphene-modified electrodes for rapid detection of HIV-1 through electrical sensing. We evaluated the effect of electrode material and geometry on the performance of the microchip to detect serially diluted, electrically conductive samples. We evaluated the optimized microchip with HIVspiked samples.

  10. Recent Developments in Miniaturized PCR-Microchips, Microarrays and Microdroplets

    PubMed Central

    Pollak, Eleanor S; Fortina, Paolo

    2012-01-01

    Microminiaturization of assays and lab-on-a-chip devices hold considerable promise for the future of analysis, especially in point-of-care testing. This article focuses on developments that have occurred during the last five years in the specific area of microchip PCR and miniaturized PCR in arrays of reaction vessels and droplets. Although, this area continues to be an active focus of research and development and the variety and ingenuity of microchip PCR and integrated microchip PCR devices continue to increase, commercialization lags behind the progress being made in digital PCR and arrays for real-time PCR.

  11. Detection of telomerase activity using microchip electrophoresis.

    PubMed

    Karasawa, Koji; Arakawa, Hidetoshi

    2015-07-01

    Telomerase participates in malignant transformation or immortalization of cells and thus has attracted attention as an anticancer drug target and diagnostic tumor marker. The telomeric repeat amplification protocol (TRAP) and improved TRAP methods (TRAP-fluorescence, TRAP-hybridization, etc.) are widely used forms of this telomerase assay. However, these approaches generally employ acrylamide gel electrophoresis after amplification of telomeric repeats by polymerase chain reaction (PCR), making these TRAP methods time consuming and technically demanding. In this study we developed a novel telomerase assay using microchip electrophoresis for rapid and highly sensitive detection of telomerase activity in cancer cells. The mixed gel of 0.8% hydroxypropyl methylcellulose (HPMC) and 0.3% polyethylene oxide (PEO) with SYBR Gold (fluorescent reagent) was used for microchip electrophoresis. As a result, the product amplified by a telomerase-positive cell could be measured in one cell per assay and detected with high reproducibility (CV=0.67%) in the short time of 100s. PMID:25980765

  12. Microchip device for liquid phase analysis

    SciTech Connect

    Ramsey, j.m.

    2000-05-01

    The lab-on-a-chip concept has enabled miniature instruments to be developed that allow the rapid execution and automation of fluidic operations such as valving, separation, dilution, mixing, and flow splitting upon the proper application of a motive (driving) force. The integration of these simple operations to perform complete, multiple-step chemical assays is rapidly becoming a reality. Such compact, monolithic devices potentially enjoy advantages in speed, cost, automation, reagent consumption, and waste generation compared to existing laboratory-scale instruments. Initial reports of these microfluidic devices focused on combining various electrokinetically driven separation methods including microchip electrophoresis, gel electrophoresis, micellar electrokinetic chromatography (MEKC) and open channel electrochromatography (OCEC) with fluidic valving to introduce sample plugs into the separation channel. Other operations have quickly been integrated with the separations and fluidic valving on these microchips. For example, integrated devices with mixers/diluters for precolumn and postcolumn analyte derivatization, deoxyribonucleic acid (DNA) restriction digests, enzyme assays, and polymerase chain reaction (PCR) amplification have been added to the basic design. Integrated mixers that can perform solvent programming for both MEKC and OCEC have also been demonstrated. These examples are simple, yet powerful, demonstrations of the potential for lab-on-a-chip devices. In this report, three key areas for improved performance of these devices are described: on-chip calibration techniques, enhanced separative performance, and enhanced detection capabilities.

  13. Chemical modification of polymeric microchip devices.

    PubMed

    Muck, Alexander; Svatos, Ales

    2007-12-15

    Analytical polymeric microchips in both fluidic and array formats offer short analysis times, coupling of many sample processing and chemical reaction steps on one platform with minimal sample and reagent consumption, as well as low cost, minimal fabrication times and disposability. However, the invariable bulk properties of most commercial polymers have driven researchers to develop new modification strategies. This article critically reviews the scope and development of chemical modifications of such polymeric chips since 2003. Surface modifications were based on chemical derivatization or activation of surface layers with reagent solutions, reactive gases and irradiation. Bulk modification of polymer chips used newly incorporation of monomers with selective chemical functionalities throughout the bulk polymer material and integrated the chip modification and fabrication into a single step. Such modifications hold a great promise for establishing a true 'lab-on-chip' as can be seen from many novel applications for modulating electroosmosis, suppressing protein adsorption in microchip capillary electrophoretic separations, extraction of analytes and for zone-specific binding of enzymes and other biomolecules. PMID:18371647

  14. Portable multiplicity counter

    DOEpatents

    Newell, Matthew R.; Jones, David Carl

    2009-09-01

    A portable multiplicity counter has signal input circuitry, processing circuitry and a user/computer interface disposed in a housing. The processing circuitry, which can comprise a microcontroller integrated circuit operably coupled to shift register circuitry implemented in a field programmable gate array, is configured to be operable via the user/computer interface to count input signal pluses receivable at said signal input circuitry and record time correlations thereof in a total counting mode, coincidence counting mode and/or a multiplicity counting mode. The user/computer interface can be for example an LCD display/keypad and/or a USB interface. The counter can include a battery pack for powering the counter and low/high voltage power supplies for biasing external detectors so that the counter can be configured as a hand-held device for counting neutron events.

  15. Neutron Damage in Mechanically-Cooled High-Purity Germanium Detectors for Field-Portable Prompt Gamma Neutron Activation Analysis (PGNAA) Systems

    SciTech Connect

    E.H. Seabury; C.J. Wharton; A.J. Caffrey; J.B. McCabe; C. DeW. Van Siclen

    2013-10-01

    Prompt Gamma Neutron Activation (PGNAA) systems require the use of a gamma-ray spectrometer to record the gamma-ray spectrum of an object under test and allow the determination of the object’s composition. Field-portable systems, such as Idaho National Laboratory’s PINS system, have used standard liquid-nitrogen-cooled high-purity germanium (HPGe) detectors to perform this function. These detectors have performed very well in the past, but the requirement of liquid-nitrogen cooling limits their use to areas where liquid nitrogen is readily available or produced on-site. Also, having a relatively large volume of liquid nitrogen close to the detector can impact some assessments, possibly leading to a false detection of explosives or other nitrogen-containing chemical. Use of a mechanically-cooled HPGe detector is therefore very attractive for PGNAA applications where nitrogen detection is critical or where liquid-nitrogen logistics are problematic. Mechanically-cooled HPGe detectors constructed from p-type germanium, such as Ortec’s trans-SPEC, have been commercially available for several years. In order to assess whether these detectors would be suitable for use in a fielded PGNAA system, Idaho National Laboratory (INL) has been performing a number of tests of the resistance of mechanically-cooled HPGe detectors to neutron damage. These detectors have been standard commercially-available p-type HPGe detectors as well as prototype n-type HPGe detectors. These tests compare the performance of these different detector types as a function of crystal temperature and incident neutron fluence on the crystal.

  16. Field portable detection of VOCs using a SAW/GC system. Final report, June 21, 1994--September 21, 1996

    SciTech Connect

    Chang, F.; Staples, E.J.

    1998-06-01

    This report describes research on a fast GC vapor analysis system which uses a new type of Surface Acoustic Wave detector technology to characterize organic contamination in soil and groundwater. The project was sponsored by the Department of Energy, Morgantown Energy Technology Center, whose mission, in addition to other goals, is the development of tools and methods for characterization, remediation, and monitoring of underground environmental conditions. The research tasks were to demonstrate detectability and specificity of a Surface Acoustic Wave Gas Chromatograph (SAW/GC) to a representative number of VOC materials followed by field demonstrations of the new technology at a DOE site. All tasks of the project were successfully carried out and a fast vapor analysis system based upon a new type of Surface Acoustic Wave detector technology was developed. The prototype analyzer has the ability to characterize organic contamination in soil and groundwater at the part per billion level in less than 10 seconds. The detector is unique because it utilized an uncoated quartz crystal, contrary to current developments of using coated crystals.

  17. A portable x-ray fluorescence instrument for analyzing dust wipe samples for lead: evaluation with field samples.

    PubMed

    Sterling, D A; Lewis, R D; Luke, D A; Shadel, B N

    2000-06-01

    Dust wipe samples collected in the field were tested by nondestructive X-ray fluorescence (XRF) followed by laboratory analysis with flame atomic absorption spectrophotometry (FAAS). Data were analyzed for precision and accuracy of measurement. Replicate samples with the XRF show high precision with an intraclass correlation coefficient (ICC) of 0.97 (P<0.0001) and an overall coefficient of variation of 11.6%. Paired comparison indicates no statistical difference (P=0.272) between XRF and FAAS analysis. Paired samples are highly correlated with an R(2) ranging between 0.89 for samples that contain paint chips and 0.93 for samples that do not contain paint chips. The ICC for absolute agreement between XRF and laboratory results was 0.95 (P<0.0001). The relative error over the concentration range of 25 to 14,200 microgram Pb is -12% (95% CI, -18 to -5). The XRF appears to be an excellent method for rapid on-site evaluation of dust wipes for clearance and risk assessment purposes, although there are indications of some confounding when paint chips are present.

  18. A hydrodynamic microchip for formation of continuous cell chains

    NASA Astrophysics Data System (ADS)

    Khoshmanesh, Khashayar; Zhang, Wei; Tang, Shi-Yang; Nasabi, Mahyar; Soffe, Rebecca; Tovar-Lopez, Francisco J.; Rajadas, Jayakumar; Mitchell, Arnan

    2014-05-01

    Here, we demonstrate the unique features of a hydrodynamic based microchip for creating continuous chains of model yeast cells. The system consists of a disk shaped microfluidic structure, containing narrow orifices that connect the main channel to an array of spoke channels. Negative pressure provided by a syringe pump draws fluid from the main channel through the narrow orifices. After cleaning process, a thin layer of water is left between the glass substrate and the polydimethylsiloxane microchip, enabling leakage beneath the channel walls. A mechanical clamp is used to adjust the operation of the microchip. Relaxing the clamp allows leakage of liquid beneath the walls in a controllable fashion, leading to formation of a long cell chain evenly distributed along the channel wall. The unique features of the microchip are demonstrated by creating long chains of yeast cells and model 15 μm polystyrene particles along the side wall and analysing the hydrogen peroxide induced death of patterned cells.

  19. Feline lost: making microchipping compulsory for domestic cats.

    PubMed

    Roberts, M

    2016-08-13

    The independent nature of cats means that they are more likely to become lost or injured than dogs. Maggie Roberts believes that microchipping of cats should be compulsory in the UK as is the case with dogs. PMID:27516564

  20. Accuracy of microchip identification in dogs and cats.

    PubMed

    Sorensen, M A; Buss, M S; Tyler, J W

    1995-09-15

    A study was performed to determine the sensitivity and specificity of a commercially available microchip identification system approximately 1 year after implantation in dogs and cats. Thirty-three dogs and 16 cats in which a microchip had been implanted and 31 dogs and 18 cats in which a microchip had never been implanted were included in the study. In cats, sensitivity and specificity of microchip identification were 1.00. In dogs, sensitivity and specificity were 0.97 and 1.00, respectively. The chip had migrated in the 1 dog with a false-negative result, but the chip remained functional, and identification was established in this dog following closer physical examination and scanning.

  1. Apparatus for Precise Indium-Bump Bonding of Microchips

    NASA Technical Reports Server (NTRS)

    Wild, Larry; Mulder, Jerry; Alvarado, Nicholas

    2005-01-01

    An improved apparatus has been designed and built for use in precise positioning and pressing of a microchip onto a substrate (which could, optionally, be another microchip) for the purpose of indium-bump bonding. The apparatus (see figure) includes the following: A stereomicroscope, A stage for precise positioning of the microchip in rotation angle (theta) about the nominally vertical pressing axis and in translation along two nominally horizontal coordinate axes (x and y), and An actuator system that causes a bonding tip to press the microchip against the substrate with a precisely controlled force. In operation, the microscope and the stage are used to position the microchip under the bonding tip and to align the indium bumps on the chip and the substrate, then the actuator system is used to apply a prescribed bonding force for a prescribed time. The improved apparatus supplants a partly similar prior apparatus that operated with less precision and repeatability, producing inconsistent and unreliable bonds. Results of the use of the prior apparatus included broken microchips, uneven bonds, and bonds characterized, variously, by overcompression or undercompression. In that apparatus, the bonding force was generated and controlled by use of a micrometer head positioned over the center of a spring-loaded scale, and the force was applied to the microchip via the scale, which was equipped for digital readout of the force. The inconsistency of results was attributed to the following causes: It was not possible to control the bonding force with sufficient precision or repeatability. Particularly troublesome was the inability to control the force at levels less than the weight of 150 g. Excessive compliance in the spring-loaded scale, combined with deviations from parallelarity of the substrate and bonding-tip surfaces, gave rise to nonuniformity in the pressure applied to the microchip, thereby generating excessive stresses and deformations in the microchip. In the

  2. Portable Instrumented Communication Library

    1993-06-10

    PICL is a subroutine library that can be used to develop parallel programs that are portable across several distributed-memory multiprocessors. PICL provides a portable syntax for key communication primitives and related system calls. It also provides portable routines to perform certain widely-used, high-level communication operations, such as global broadcast and global summation. PICL provides execution tracing that can be used to monitor performance or to aid in debugging.

  3. Analysis of Twenty-Two Performance Properties of Diesel, Gasoline, and Jet Fuels Using a Field-Portable Near-Infrared (NIR) Analyzer.

    PubMed

    Brouillette, Carl; Smith, Wayne; Shende, Chetan; Gladding, Zack; Farquharson, Stuart; Morris, Robert E; Cramer, Jeffrey A; Schmitigal, Joel

    2016-05-01

    The change in custody of fuel shipments at depots, pipelines, and ports could benefit from an analyzer that could rapidly verify that properties are within specifications. To meet this need, the design requirements for a fuel analyzer based on near-infrared (NIR) spectroscopy, such as spectral region and resolution, were examined. It was found that the 1000 to 1600 nm region, containing the second CH overtone and combination vibrational modes of hydrocarbons, provided the best near-infrared to fuel property correlations when path length was taken into account, whereas 4 cm(-1) resolution provided only a modest improvement compared to 16 cm(-1) resolution when four or more latent variables were used. Based on these results, a field-portable near-infrared fuel analyzer was built that employed an incandescent light source, sample compartment optics to hold 2 mL glass sample vials with ∼1 cm path length, a transmission grating, and a 256 channel InGaAs detector that measured the above stated wavelength range with 5-6 nm (∼32 cm(-1)) resolution. The analyzer produced high signal-to-noise ratio (SNR) spectra of samples in 5 s. Twenty-two property correlation models were developed for diesel, gasoline, and jet fuels with root mean squared error of correlation - cross-validated values that compared favorably to corresponding ASTM reproducibility values. The standard deviations of predicted properties for repeat measurements at 4, 24, and 38℃ were often better than ASTM documented repeatability values. The analyzer and diesel property models were tested by measuring seven diesel samples at a local ASTM certification laboratory. The standard deviations between the analyzer determined values and the ASTM measured values for these samples were generally better than the model root mean squared error of correlation-cross-validated values for each property.

  4. Analysis of Twenty-Two Performance Properties of Diesel, Gasoline, and Jet Fuels Using a Field-Portable Near-Infrared (NIR) Analyzer.

    PubMed

    Brouillette, Carl; Smith, Wayne; Shende, Chetan; Gladding, Zack; Farquharson, Stuart; Morris, Robert E; Cramer, Jeffrey A; Schmitigal, Joel

    2016-05-01

    The change in custody of fuel shipments at depots, pipelines, and ports could benefit from an analyzer that could rapidly verify that properties are within specifications. To meet this need, the design requirements for a fuel analyzer based on near-infrared (NIR) spectroscopy, such as spectral region and resolution, were examined. It was found that the 1000 to 1600 nm region, containing the second CH overtone and combination vibrational modes of hydrocarbons, provided the best near-infrared to fuel property correlations when path length was taken into account, whereas 4 cm(-1) resolution provided only a modest improvement compared to 16 cm(-1) resolution when four or more latent variables were used. Based on these results, a field-portable near-infrared fuel analyzer was built that employed an incandescent light source, sample compartment optics to hold 2 mL glass sample vials with ∼1 cm path length, a transmission grating, and a 256 channel InGaAs detector that measured the above stated wavelength range with 5-6 nm (∼32 cm(-1)) resolution. The analyzer produced high signal-to-noise ratio (SNR) spectra of samples in 5 s. Twenty-two property correlation models were developed for diesel, gasoline, and jet fuels with root mean squared error of correlation - cross-validated values that compared favorably to corresponding ASTM reproducibility values. The standard deviations of predicted properties for repeat measurements at 4, 24, and 38℃ were often better than ASTM documented repeatability values. The analyzer and diesel property models were tested by measuring seven diesel samples at a local ASTM certification laboratory. The standard deviations between the analyzer determined values and the ASTM measured values for these samples were generally better than the model root mean squared error of correlation-cross-validated values for each property. PMID:27006025

  5. Comparison of field portable measurements of ultrafine TiO2: X-ray fluorescence, laser-induced breakdown spectroscopy, and Fourier-transform infrared spectroscopy.

    PubMed

    LeBouf, Ryan F; Miller, Arthur L; Stipe, Christopher; Brown, Jonathan; Murphy, Nate; Stefaniak, Aleksandr B

    2013-06-01

    Laboratory measurements of ultrafine titanium dioxide (TiO2) particulate matter loaded on filters were made using three field portable methods (X-ray fluorescence (XRF), laser-induced breakdown spectroscopy (LIBS), and Fourier-transform infrared (FTIR) spectroscopy) to assess their potential for determining end-of-shift exposure. Ultrafine TiO2 particles were aerosolized and collected onto 37 mm polycarbonate track-etched (PCTE) filters in the range of 3 to 578 μg titanium (Ti). Limit of detection (LOD), limit of quantification (LOQ), and calibration fit were determined for each measurement method. The LOD's were 11.8, 0.032, and 108 μg Ti per filter, for XRF, LIBS, and FTIR, respectively and the LOQ's were 39.2, 0.11, and 361 μg Ti per filter, respectively. The XRF calibration curve was linear over the widest dynamic range, up to the maximum loading tested (578 μg Ti per filter). LIBS was more sensitive but, due to the sample preparation method, the highest loaded filter measurable was 252 μg Ti per filter. XRF and LIBS had good predictability measured by regressing the predicted mass to the gravimetric mass on the filter. XRF and LIBS produced overestimations of 4% and 2%, respectively, with coefficients of determination (R(2)) of 0.995 and 0.998. FTIR measurements were less dependable due to interference from the PCTE filter media and overestimated mass by 2% with an R(2) of 0.831. PMID:23632878

  6. Comparison of field portable measurements of ultrafine TiO2: X-ray fluorescence, laser-induced breakdown spectroscopy, and Fourier-transform infrared spectroscopy.

    PubMed

    LeBouf, Ryan F; Miller, Arthur L; Stipe, Christopher; Brown, Jonathan; Murphy, Nate; Stefaniak, Aleksandr B

    2013-06-01

    Laboratory measurements of ultrafine titanium dioxide (TiO2) particulate matter loaded on filters were made using three field portable methods (X-ray fluorescence (XRF), laser-induced breakdown spectroscopy (LIBS), and Fourier-transform infrared (FTIR) spectroscopy) to assess their potential for determining end-of-shift exposure. Ultrafine TiO2 particles were aerosolized and collected onto 37 mm polycarbonate track-etched (PCTE) filters in the range of 3 to 578 μg titanium (Ti). Limit of detection (LOD), limit of quantification (LOQ), and calibration fit were determined for each measurement method. The LOD's were 11.8, 0.032, and 108 μg Ti per filter, for XRF, LIBS, and FTIR, respectively and the LOQ's were 39.2, 0.11, and 361 μg Ti per filter, respectively. The XRF calibration curve was linear over the widest dynamic range, up to the maximum loading tested (578 μg Ti per filter). LIBS was more sensitive but, due to the sample preparation method, the highest loaded filter measurable was 252 μg Ti per filter. XRF and LIBS had good predictability measured by regressing the predicted mass to the gravimetric mass on the filter. XRF and LIBS produced overestimations of 4% and 2%, respectively, with coefficients of determination (R(2)) of 0.995 and 0.998. FTIR measurements were less dependable due to interference from the PCTE filter media and overestimated mass by 2% with an R(2) of 0.831.

  7. Metal contamination at recreational boatyards linked to the use of antifouling paints-investigation of soil and sediment with a field portable XRF.

    PubMed

    Lagerström, Maria; Norling, Matz; Eklund, Britta

    2016-05-01

    The application of a field portable X-ray fluorescence spectrometer (FPXRF) to measure Cu, Zn, and Pb in soil and sediments at recreational boatyards by Lake Mälaren in Sweden was investigated. Confirmatory chemical analysis on freeze-dried samples shows that, ex situ, the FPXRF produces definitive level data for Cu and Zn and quantitative screening data for Pb, according to USEPA criteria for data quality. Good agreement was also found between the ex situ measurements and the in situ screening. At each of the two studied boatyards, >40 in situ soil measurements were carried out. Statistical differences in soil concentration based on land use were consequently found: the areas used for boat storage and maintenance were significantly higher in Cu and Zn than the areas used for car parking and transportation. The metal pollution in the boat storage areas is therefore shown to be directly linked to hull maintenance activities during which metal-containing antifouling paint particles are shed, end up on the ground, and consequently pollute the soil. In the boat storage areas, the Cu and Zn concentrations often exceeded the national guideline values for soil. In this study, they were also shown to increase with increasing age of the boatyard operation. Pb soil concentrations were only elevated at a few measurement points, reflecting the phasing out of Pb compounds from antifouling products over the past 2 decades. In the surface sediments, concentrations of Cu and Zn were 2-3 times higher compared to deeper levels. No decrease in metal concentration with time was found in the sediments, indicating that boat owners are not complying with the ban of biocide-containing paints in freshwater introduced over 20 years ago.

  8. Microchip-Embedded Capacitors for Implantable Neural Stimulators

    NASA Astrophysics Data System (ADS)

    Auciello, Orlando

    Miniaturization of microchips for implantation in the human body (e.g., microchip for the artificial retina to restore sight to people blinded by retina photoreceptors degeneration) requires the integration of high-capacitance (≥ 10 μF) energy-storage capacitors into the microchip. These capacitors would be based on high-dielectric constant layers, preferably made of materials that are bioinert (not affected by human body fluids) and are biocompatible (do not elicit adverse reactions in the human body). This chapter focuses on reviewing the work being done at Argonne National Laboratory (Materials Science Division and Center for Nanoscale Materials) to develop high-capacitance microchip-embedded capacitors based on novel high-K dielectric layers (TiAlOx or TiO2/Al2O3 superlattices). The microchip-embedded capacitor provides energy storage and electromagnetic signal coupling needed for neural stimulations. Advances in neural prostheses such as artificial retinas and cochlear implants require miniaturization of device size to minimize tissue damage and improve device/tissue interfaces in the human body. Therefore, development of microchip-embedded capacitors is critical to achieve full-implantable biomedical device miniaturization.

  9. Etching of glass microchips with supercritical water.

    PubMed

    Karásek, Pavel; Grym, Jakub; Roth, Michal; Planeta, Josef; Foret, František

    2015-01-01

    A novel method of etching channels in glass microchips with the most tunable solvent, water, was tested as an alternative to common hydrogen fluoride-containing etchants. The etching properties of water strongly depend on temperature and pressure, especially in the vicinity of the water critical point. The chips were etched at the subcritical, supercritical and critical temperature of water, and the resulting channel shape, width, depth and surface morphology were studied by scanning electron microscopy and 3D laser profilometry. Channels etched with the hot water were compared with the chips etched with standard hydrogen fluoride-containing solution. Depending on the water pressure and temperature, the silicate dissolved from the glass could be re-deposited on the channel surface. This interesting phenomenon is described together with the conditions necessary for its utilization. The results illustrate the versatility of pure water as a glass etching and surface morphing agent.

  10. BEC on a microchip: integrated coherent manipulation of matter waves

    NASA Astrophysics Data System (ADS)

    Reichel, Jakob

    2002-03-01

    We use the magnetic fields generated by lithographic conductor patterns to trap and manipulate cold neutral atoms in close proximity to a microchip surface. Recently we succeeded in achieving Bose-Einstein-condensation in such a "chip trap". Indeed, the strong field gradients generated by the microscopic conductors enable very strongly confining traps, ideally suited for evaporative cooling. Thus, the new technique not only speeds up the process of condensate production, it also simplifies the apparatus significantly. Moreover, the benefits of lithography and integration now open the door to new applications of condensed atomic ensembles. Functions such as coherent splitting, transport and controlled interactions can be integrated on the same chip. Because of such features, the chip trap approach appears well-suited for implementing quantum computing schemes with neutral atoms. As a first step, we have already realized a "conveyor belt" which coherently transports the trapped condensate along the chip in a distance of less than 100 microns from the surface. Experiments under way include single atom detection on the chip, as well as an integrated atom interferometer. This will enable us to measure the phase shift due to a controlled collision between two trapped atoms.

  11. Electrochemical methods in conjunction with capillary and microchip electrophoresis.

    PubMed

    Mark, Jonas J P; Scholz, Rebekka; Matysik, Frank-Michael

    2012-12-01

    Electromigrative techniques such as capillary and microchip electrophoresis (CE and MCE) are inherently associated with various electrochemical phenomena. The electrolytic processes occurring in the buffer reservoirs have to be considered for a proper design of miniaturized electrophoretic systems and a suitable selection of buffer composition. In addition, the control of the electroosmotic flow plays a crucial role for the optimization of CE/MCE separations. Electroanalytical methods have significant importance in the field of detection in conjunction with CE/MCE. At present, amperometric detection and contactless conductivity detection are the predominating electrochemical detection methods for CE/MCE. This paper reviews the most recent trends in the field of electrochemical detection coupled to CE/MCE. The emphasis is on methodical developments and new applications that have been published over the past five years. A rather new way for the implementation of electrochemical methods into CE systems is the concept of electrochemically assisted injection which involves the electrochemical conversions of analytes during the injection step. This approach is particularly attractive in hyphenation to mass spectrometry (MS) as it widens the range of CE-MS applications. An overview of recent developments of electrochemically assisted injection coupled to CE is presented.

  12. PORTABLE ACOUSTIC MONITORING PACKAGE (PAMP)

    SciTech Connect

    John L. Loth; Gary J. Morris; George M. Palmer; Richard Guiler; Patrick Browning

    2004-07-20

    The Portable Acoustic Monitoring Package (PAMP) has been designed to record and monitor the acoustic signal in natural gas transmission lines. In particular the three acoustic signals associated with a line leak. The system is portable ({approx}30 lbs) and is designed for line pressures up to 1000 psi. It has become apparent that cataloging of the various background acoustic signals in natural gas transmission line is very important if a system to identify leak signals is to be developed. The low-pressure (0-200 psig) laboratory test phase has been completed and a number of field trials have been conducted. Before the cataloging phase could begin, a few problems identified in field trials identified had to be corrected such as: (1) Decreased microphone sensitivity at line pressures above 250 psig. (2) The inability to deal with large data sets collected when cataloging the variety of signals in a transmission line. (3) The lack of an available online acoustic calibration system. These problems have been solved and the WVU PAMP is now fully functional over the entire pressure range found in the Natural Gas transmission lines in this region. Field portability and reliability have been greatly improved. Data collection and storage have also improved to the point were the full acoustic spectrum of acoustic signals can be accurately cataloged, recorded and described.

  13. Rapid analysis of perchlorate in drinking water at parts per billion levels using microchip electrophoresis.

    PubMed

    Gertsch, Jana C; Noblitt, Scott D; Cropek, Donald M; Henry, Charles S

    2010-05-01

    A microchip capillary electrophoresis (MCE) system has been developed for the determination of perchlorate in drinking water. The United States Environmental Protection Agency (USEPA) recently proposed a health advisory limit for perchlorate in drinking water of 15 parts per billion (ppb), a level requiring large, sophisticated instrumentation, such as ion chromatography coupled with mass spectrometry (IC-MS), for detection. An inexpensive, portable system is desired for routine online monitoring applications of perchlorate in drinking water. Here, we present an MCE method using contact conductivity detection for perchlorate determination. The method has several advantages, including reduced analysis times relative to IC, inherent portability, high selectivity, and minimal sample pretreatment. Resolution of perchlorate from more abundant ions was achieved using zwitterionic, sulfobetaine surfactants, N-hexadecyl-N,N-dimethyl-3-ammonio-1-propane sulfonate (HDAPS) and N-tetradecyl-N,N-dimethyl-3-ammonio-1-propane sulfonate (TDAPS). The system performance and the optimization of the separation chemistry, including the use of these surfactants to resolve perchlorate from other anions, are discussed in this work. The system is capable of detection limits of 3.4 +/- 1.8 ppb (n = 6) in standards and 5.6 +/- 1.7 ppb (n = 6) in drinking water.

  14. Portable peak flow meters.

    PubMed

    McNaughton, J P

    1997-02-01

    There are several portable peak flow meters available. These instruments vary in construction and performance. Guidelines are recommended for minimum performance and testing of portable peak flow meters, with the aim of establishing a procedure for standardizing all peak flow meters. Future studies to clarify the usefulness of mechanical test apparatus and clinical trials of peak flow meters are also recommended. PMID:9098706

  15. Portable seat lift

    NASA Technical Reports Server (NTRS)

    Weddendorf, Bruce (Inventor)

    1994-01-01

    A portable seat lift that can help individuals either (1) lower themselves to a sitting position or (2) raise themselves to a standing position is presented. The portable seat lift consists of a seat mounted on a base with two levers, which are powered by a drive unit.

  16. Microchip-based immunomagnetic detection of circulating tumor cells.

    PubMed

    Hoshino, Kazunori; Huang, Yu-Yen; Lane, Nancy; Huebschman, Michael; Uhr, Jonathan W; Frenkel, Eugene P; Zhang, Xiaojing

    2011-10-21

    Screening for circulating tumor cells (CTCs) in blood has been an object of interest for evidence of progressive disease, status of disease activity, recognition of clonal evolution of molecular changes and for possible early diagnosis of cancer. We describe a new method of microchip-based immunomagnetic CTC detection, in which the benefits of both immunomagnetic assay and the microfluidic device are combined. As the blood sample flows through the microchannel closely above arrayed magnets, cancer cells labeled with magnetic nanoparticles are separated from blood flow and deposited at the bottom wall of the glass coverslip, which allows direct observation of captured cells with a fluorescence microscope. A polydimethylsiloxane (PDMS)-based microchannel fixed on a glass coverslip was used to screen blood samples. The thin, flat dimensions of the microchannel, combined with the sharp magnetic field gradient in the vicinity of arrayed magnets with alternate polarities, lead to an effective capture of labeled cells. Compared to the commercially available CellSearch™ system, fewer (25%) magnetic particles are required to achieve a comparable capture rate, while the screening speed (at an optimal blood flow rate of 10 mL h(-1)) is more than five times faster than those reported previously with a microchannel-based assay. For the screening experiment, blood drawn from healthy subjects into CellSave™ tubes was spiked with cultured cancer cell lines of COLO205 and SKBR3. The blood was then kept at room temperature for 48 hours before the screening, emulating the actual clinical cases of blood screening. Customized Fe(3)O(4) magnetic nanoparticles (Veridex Ferrofluid™) conjugated to anti-epithelial cell adhesion molecule (EpCAM) antibodies were introduced into the blood samples to label cancer cells, and the blood was then run through the microchip device to capture the labelled cells. After capture, the cells were stained with fluorescent labelled anti

  17. Problems Associated with the Microchip Data of Stray Dogs and Cats Entering RSPCA Queensland Shelters

    PubMed Central

    Lancaster, Emily; Rand, Jacquie; Collecott, Sheila; Paterson, Mandy

    2015-01-01

    Simple Summary Microchip identification has become an important tool to reunite stray dogs and cats with their owners, and is now compulsory in most states of Australia. Improvement of the microchipping system in Australia is limited by a lack of published Australian data documenting the problems experienced by shelter staff when using microchip data to contact the owner of a stray animal. In this study we determine the character and frequency of inaccurate microchip data to identify weaknesses in the current microchipping system. This information could be used to develop strategies that increase the accuracy of microchip data that will increase the reclaiming of stray animals. Abstract A lack of published information documenting problems with the microchip data for the reclaiming of stray animals entering Australian shelters limits improvement of the current microchipping system. A retrospective study analysing admission data for stray, adult dogs (n = 7258) and cats (n = 6950) entering the Royal Society for the Prevention of Cruelty to Animals (RSPCA) Queensland between January 2012 and December 2013 was undertaken to determine the character and frequency of microchip data problems and their impact on outcome for the animal. Only 28% of dogs and 9% of cats were microchipped, and a substantial proportion (37%) had problems with their data, including being registered to a previous owner or organisation (47%), all phone numbers incorrect/disconnected (29%), and the microchip not registered (14%). A higher proportion of owners could be contacted when the microchip had no problems, compared to those with problems (dogs, 93% vs. 70%; cats, 75% vs. 41%). The proportion of animals reclaimed declined significantly between microchipped animals with no data problems, microchipped animals with data problems and non-microchipped animals—87%, 69%, and 37%, respectively, for dogs and 61%, 33%, and 5%, respectively, for cats. Strategies are needed to increase the accuracy of

  18. Portable sensor for hazardous waste

    SciTech Connect

    Piper, L.G.; Fraser, M.E.; Davis, S.J.

    1995-10-01

    We are beginning the second phase of a three and a half year program designed to develop a portable monitor for sensitive hazardous waste detection. The ultimate goal of the program is to develop our concept to the prototype instrument level. Our monitor will be a compact, portable instrument that will allow real-time, in situ, monitoring of hazardous wastes. This instrument will be able to provide the means for rapid field screening of hazardous waste sites to map the areas of greatest contamination. Remediation efforts can then focus on these areas. Further, our instrument can show whether cleanup technologies are successful at reducing hazardous materials concentrations below regulated levels, and will provide feedback to allow changes in remediation operations, if necessary, to enhance their efficacy.

  19. Rapid diagnosis of avian influenza virus in wild birds: Use of a portable rRT-PCR and freeze-dried reagents in the field

    USGS Publications Warehouse

    Takekawa, J.Y.; Hill, N.J.; Schultz, A.K.; Iverson, S.A.; Cardona, C.J.; Boyce, W.M.; Dudley, J.P.

    2011-01-01

    Wild birds have been implicated in the spread of highly pathogenic avian influenza (HPAI) of the H5N1 subtype, prompting surveillance along migratory flyways. Sampling of wild birds for avian influenza virus (AIV) is often conducted in remote regions, but results are often delayed because of the need to transport samples to a laboratory equipped for molecular testing. Real-time reverse transcriptase polymerase chain reaction (rRT-PCR) is a molecular technique that offers one of the most accurate and sensitive methods for diagnosis of AIV. The previously strict lab protocols needed for rRT-PCR are now being adapted for the field. Development of freeze-dried (lyophilized) reagents that do not require cold chain, with sensitivity at the level of wet reagents has brought on-site remote testing to a practical goal. Here we present a method for the rapid diagnosis of AIV in wild birds using an rRT-PCR unit (Ruggedized Advanced Pathogen Identification Device or RAPID, Idaho Technologies, Salt Lake City, UT) that employs lyophilized reagents (Influenza A Target 1 Taqman; ASAY-ASY-0109, Idaho Technologies). The reagents contain all of the necessary components for testing at appropriate concentrations in a single tube: primers, probes, enzymes, buffers and internal positive controls, eliminating errors associated with improper storage or handling of wet reagents. The portable unit performs a screen for Influenza A by targeting the matrix gene and yields results in 2-3 hours. Genetic subtyping is also possible with H5 and H7 primer sets that target the hemagglutinin gene. The system is suitable for use on cloacal and oropharyngeal samples collected from wild birds, as demonstrated here on the migratory shorebird species, the western sandpiper (Calidrus mauri) captured in Northern California. Animal handling followed protocols approved by the Animal Care and Use Committee of the U.S. Geological Survey Western Ecological Research Center and permits of the U.S. Geological Survey

  20. Rapid Diagnosis of Avian Influenza Virus in Wild Birds: Use of a Portable rRT-PCR and Freeze-dried Reagents in the Field

    PubMed Central

    Takekawa, John Y.; Hill, Nichola J.; Schultz, Annie K.; Iverson, Samuel A.; Cardona, Carol J.; Boyce, Walter M.; Dudley, Joseph P.

    2011-01-01

    Wild birds have been implicated in the spread of highly pathogenic avian influenza (HPAI) of the H5N1 subtype, prompting surveillance along migratory flyways. Sampling of wild birds for avian influenza virus (AIV) is often conducted in remote regions, but results are often delayed because of the need to transport samples to a laboratory equipped for molecular testing. Real-time reverse transcriptase polymerase chain reaction (rRT-PCR) is a molecular technique that offers one of the most accurate and sensitive methods for diagnosis of AIV. The previously strict lab protocols needed for rRT-PCR are now being adapted for the field. Development of freeze-dried (lyophilized) reagents that do not require cold chain, with sensitivity at the level of wet reagents has brought on-site remote testing to a practical goal. Here we present a method for the rapid diagnosis of AIV in wild birds using an rRT-PCR unit (Ruggedized Advanced Pathogen Identification Device or RAPID, Idaho Technologies, Salt Lake City, UT) that employs lyophilized reagents (Influenza A Target 1 Taqman; ASAY-ASY-0109, Idaho Technologies). The reagents contain all of the necessary components for testing at appropriate concentrations in a single tube: primers, probes, enzymes, buffers and internal positive controls, eliminating errors associated with improper storage or handling of wet reagents. The portable unit performs a screen for Influenza A by targeting the matrix gene and yields results in 2-3 hours. Genetic subtyping is also possible with H5 and H7 primer sets that target the hemagglutinin gene. The system is suitable for use on cloacal and oropharyngeal samples collected from wild birds, as demonstrated here on the migratory shorebird species, the western sandpiper (Calidrus mauri) captured in Northern California. Animal handling followed protocols approved by the Animal Care and Use Committee of the U.S. Geological Survey Western Ecological Research Center and permits of the U.S. Geological Survey

  1. A portable luminescence dating instrument

    NASA Astrophysics Data System (ADS)

    Kook, M. H.; Murray, A. S.; Lapp, T.; Denby, P. H.; Ankjærgaard, C.; Thomsen, K.; Jain, M.; Choi, J. H.; Kim, G. H.

    2011-06-01

    We describe a portable luminescence reader suitable for use in remote localities in the field. The instrument weighs about 8 kg and is based around a 30 mm bialkali photomultiplier detecting signals through a glass filter centered on 340 nm. Stimulation is by 470 nm blue LEDs (24 W in total) operating in both continuous wave and pulsed mode; photon counting can be gated such that it is active only during the pulse off-period. There are also two bleaching light sources (470 nm, 5 W and 940 nm, 3 W), and the luminescence signals can be regenerated using a cold-cathode 30 kV X-ray tube, delivering ˜0.06 Gy.s -1. The three position sampling device has a heating element under each sampling position, able to heat the sample at 3 °C.s -1 up to at least 250 °C. The sampler can be inserted into unconsolidated sediments, and is designed to prevent exposure of the mineral grains to ambient light during sampling. The performance of the instrument in terms of sensitivity and reproducibility is comparable to that of the standard bench-top laboratory TL/OSL Risø reader. We show that the portable luminescence reader is able to measure accurately an ˜20 Gy quartz burial dose in a natural (unpretreated, no mineral separation) sandy sediment. We also show that, because of the configuration of the measurement head, the portable reader can be used to measure radioluminescence at elevated temperature in the presence of stimulation light; this facility is not available on conventional bench-top instruments. It is concluded that the portable luminescence reader can be used to accurately determine the quartz burial dose in loose sandy sediments in the field, without sample preparation or darkroom facilities.

  2. Human portable preconcentrator system

    DOEpatents

    Linker, Kevin L.; Bouchier, Francis A.; Hannum, David W.; Rhykerd, Jr., Charles L.

    2003-01-01

    A preconcentrator system and apparatus suited to human portable use wherein sample potentially containing a target chemical substance is drawn into a chamber and through a pervious screen. The screen is adapted to capture target chemicals and then, upon heating, to release those chemicals into the chamber. Chemicals captured and then released in this fashion are then carried to a portable chemical detection device such as a portable ion mobility spectrometer. In the preferred embodiment, the means for drawing sample into the chamber comprises a reversible fan which, when operated in reverse direction, creates a backpressure that facilitates evolution of captured target chemicals into the chamber when the screen is heated.

  3. CE microchips: an opened gate to food analysis.

    PubMed

    Escarpa, Alberto; González, María Cristina; Crevillén, Agustín González; Blasco, Antonio Javier

    2007-03-01

    CE microchips are the first generation of micrototal analysis systems (-TAS) emerging in the miniaturization scene of food analysis. CE microchips for food analysis are fabricated in both glass and polymer materials, such as PDMS and poly(methyl methacrylate) (PMMA), and use simple layouts of simple and double T crosses. Nowadays, the detection route preferred is electrochemical in both, amperometry and conductivity modes, using end-channel and contactless configurations, respectively. Food applications using CE microchips are now emerging since food samples present complex matrices, the selectivity being a very important challenge because the total integration of analytical steps into microchip format is very difficult. As a consequence, the first contributions that have recently appeared in the relevant literature are based primarily on fast separations of analytes of high food significance. These protocols are combined with different strategies to achieve selectivity using a suitable nonextensive sample preparation and/or strategically choosing detection routes. Polyphenolic compounds, amino acids, preservatives, and organic and inorganic ions have been studied using CE microchips. Thus, new and exciting future expectations arise in the domain of food analysis. However, several drawbacks could easily be found and assumed within the miniaturization map.

  4. Inexpensive portable drug detector

    NASA Technical Reports Server (NTRS)

    Dimeff, J.; Heimbuch, A. H.; Parker, J. A.

    1977-01-01

    Inexpensive, easy-to-use, self-scanning, self-calibrating, portable unit automatically graphs fluorescence spectrum of drug sample. Device also measures rate of movement through chromatographic column for forensic and medical testing.

  5. Rapid bonding of Pyrex glass microchips.

    PubMed

    Akiyama, Yoshitake; Morishima, Keisuke; Kogi, Atsuna; Kikutani, Yoshikuni; Tokeshi, Manabu; Kitamori, Takehiko

    2007-03-01

    A newly developed vacuum hot press system has been specially designed for the thermal bonding of glass substrates in the fabrication process of Pyrex glass microchemical chips. This system includes a vacuum chamber equipped with a high-pressure piston cylinder and carbon plate heaters. A temperature of up to 900 degrees C and a force of as much as 9800 N could be applied to the substrates in a vacuum atmosphere. The Pyrex substrates bonded with this system under different temperatures, pressures, and heating times were evaluated by tensile strength tests, by measurements of thickness, and by observations of the cross-sectional shapes of the microchannels. The optimal bonding conditions of the Pyrex glass substrates were 570 degrees C for 10 min under 4.7 N/mm(2) of applied pressure. Whereas more than 16 h is required for thermal bonding with a conventional furnace, the new system could complete the whole bonding processes within just 79 min, including heating and cooling periods. Such improvements should considerably enhance the production rate of Pyrex glass microchemical chips. Whereas flat and dust-free surfaces are required for conventional thermal bonding, especially without long and repeated heating periods, our hot press system could press a fine dust into glass substrates so that even the areas around the dust were bonded. Using this capability, we were able to successfully integrate Pt/Ti thin film electrodes into a Pyrex glass microchip.

  6. Serial dilution microchip for cytotoxicity test

    NASA Astrophysics Data System (ADS)

    Bang, Hyunwoo; Lim, Sun Hee; Lee, Young Kyung; Chung, Seok; Chung, Chanil; Han, Dong-Chul; Chang, Jun Keun

    2004-08-01

    Today's pharmaceutical industry is facing challenges resulting from the vast increases in sample numbers produced by high-throughput screening (HTS). In addition, the bottlenecks created by increased demand for cytotoxicity testing (required to assess compound safety) are becoming a serious problem. We have developed a polymer PDMS (polydimethylsiloxane) based microfluidic device that can perform a cytotoxicity test in a rapid and reproducible manner. The concept that the device includes is well adjustable to automated robots in huge HTS systems, so we can think of it as a potential dilution and delivery module. Cytotoxicity testing is all about the dilution and dispensing of a drug sample. Previously, we made a PDMS based microfluidic device which automatically and precisely diluted drugs with a buffer solution with serially increasing concentrations. This time, the serially diluted drug solution was directly delivered to 96 well plates for cytotoxicity testing. Cytotoxic paclitaxel solution with 2% RPMI 1640 has been used while carrying out cancerous cell based cytotoxicity tests. We believe that this rapid and robust use of the PDMS microchip will overcome the growing problem in cytotoxicity testing for HTS.

  7. A microchip platform for structural oncology applications

    PubMed Central

    Winton, Carly E; Gilmore, Brian L; Demmert, Andrew C; Karageorge, Vasilea; Sheng, Zhi; Kelly, Deborah F

    2016-01-01

    Recent advances in the development of functional materials offer new tools to dissect human health and disease mechanisms. The use of tunable surfaces is especially appealing as substrates can be tailored to fit applications involving specific cell types or tissues. Here we use tunable materials to facilitate the three-dimensional (3D) analysis of BRCA1 gene regulatory complexes derived from human cancer cells. We employed a recently developed microchip platform to isolate BRCA1 protein assemblies natively formed in breast cancer cells with and without BRCA1 mutations. The captured assemblies proved amenable to cryo-electron microscopy (EM) imaging and downstream computational analysis. Resulting 3D structures reveal the manner in which wild-type BRCA1 engages the RNA polymerase II (RNAP II) core complex that contained K63-linked ubiquitin moieties—a putative signal for DNA repair. Importantly, we also determined that molecular assemblies harboring the BRCA15382insC mutation exhibited altered protein interactions and ubiquitination patterns compared to wild-type complexes. Overall, our analyses proved optimal for developing new structural oncology applications involving patient-derived cancer cells, while expanding our knowledge of BRCA1’s role in gene regulatory events. PMID:27583302

  8. Cryogenic Tm:YAP microchip laser

    NASA Astrophysics Data System (ADS)

    Hubka, Zbyněk.; Å ulc, Jan; Jelínková, Helena; Nejezchleb, Karel; Å koda, Václav

    2016-04-01

    The spectral characteristics of laser active media, and thus those of the laser output, are temperature dependent. Specifically, in almost every crystal host, cooling to low temperatures leads to better heat removal, a higher efficiency and output power, and a reduced lasing threshold. Tm-ion doped lasers have an emission wavelength around 2 μm and are important in medicine for soft tissue cutting and hemostasis, as well as in LIDAR or atmosphere sensing technology. This paper presents the performance-temperature dependency of a 4 at. % doped Tm:YAP microchip. During the experiment the Tm:YAP crystal was placed inside an evacuated liquid nitrogen cryostat on a cooling finger. As its temperature was varied from 80 K to 340 K, changes were observed in the absorption spectrum, ranging from 750 nm to 2000 nm and in the fluorescence spectrum from 1600 nm to 2050 nm. Fluorescence lifetime was seen to rise and fall with decreasing temperature. The laser was pumped by a 792 nm laser diode and at 80 K the maximum output peak power of the laser was 4.6 W with 23 % slope efficiency and 0.6 W threshold, compared to 2.4 W output peak power, 13 % slope efficiency and 3.3 W threshold when at 340 K. The laser emission wavelength changed from 1883 nm to 1993 nm for 80 K and 300 K, respectively.

  9. Portable treatment systems study

    SciTech Connect

    Sherick, M.J.; Schwinkendorf, W.E.; Bechtold, T.E.; Cole, L.T.

    1997-03-01

    In developing their Site Treatment Plans (STPs), many of the Department of Energy installations identified some form of portable treatment, to facilitate compliant disposition of select mixed low-level wastestreams. The Environmental Management Office of Science and Technology requested that a systems study be performed to better define the potential role of portable treatment with respect to mixed low-level waste, highlight obstacles to implementation, and identify opportunities for future research and development emphasis. The study was performed by first establishing a representative set of mixed waste, then formulating portable treatment system concepts to meet the required processing needs for these wastes. The portable systems that were conceptualized were evaluated and compared to a fixed centralized treatment alternative. The system evaluations include a life-cycle cost analysis and an assessment of regulatory, institutional, and technical issues associated with the potential use of portable systems. The results of this study show that when all costs are included, there are no significant cost differences between portable systems and fixed systems. However, it is also emphasized that many uncertainties exist that could impact the cost of implementing portable treatment systems. Portable treatment could be made more attractive through private sector implementation, although there is little economic incentive for a commercial vendor to develop small, specialized treatment capabilities with limited applicability. Alternatively, there may also be valid reasons why fixed units cannot be used for some problematic wastestreams. In any event, there are some site-specific problems that still need to be addressed, and there may be some opportunity for research and development to make a positive impact in these areas.

  10. Portable Dental System

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Portable dental system provides dental care in isolated communities. System includes a patient's chair and a dentist's stool, an X-ray machine and a power unit, all of which fold into compact packages. A large yellow "pumpkin" is a collapsible compressed air tank. Portable system has been used successfully in South America in out of the way communities with this back-packable system, and in American nursing homes. This product is no longer manufactured.

  11. Acupuncture Sample Injection for Microchip Capillary Electrophoresis and Electrokinetic Chromatography.

    PubMed

    Ha, Ji Won; Hahn, Jong Hoon

    2016-05-01

    A simple nanoliter-scale injection technique was developed for polydimethylsiloxane (PDMS) microfluidic devices to form the well-defined sample plugs in microfluidic channels. Sample injection was achieved by performing acupuncture on a channel with a needle and applying external pressure to a syringe. This technique allowed us to achieve reproducible injection of a 3-nL segment into a microchannel for PDMS microchip-based capillary electrophoresis (CE). Capillary zone electrophoresis (CZE) and capillary electrochromatography (CEC) with bead packing were successfully performed by applying a single potential in the most simplified straight channel. The advantages of this acupuncture injection over the electrokinetic injection in microchip CE include capability of minimizing sample loss and voltage control hardware, capability of serial injections of different sample solutions into a same microchannel, capability of injecting sample plugs into any position of a microchannel, independence on sample solutions during the loading step, and ease in making microchips due to the straight channel, etc. PMID:27056036

  12. Optical microsystems with microchip lasers and micro-optics

    NASA Astrophysics Data System (ADS)

    Fulbert, Laurent R.; Molva, Engin; Marty, Jeannine; Thony, Philippe; Rabarot, Marc; Ferrand, Bernard

    1999-03-01

    The microchip laser is the most compact and the simplest diode pumped solid state laser, with a typical dimension of 0.5 mm3. In spite of the extreme simplicity of this concept which was described in sixties, the first devices have been realized much later in eighties, in different laboratories in the world. The main advantage of the microchip laser is its ability to be fabricated with collective fabrication processes, using techniques such as currently used in microelectronics, allowing a low cost mass production with a good reproducibility and reliability. The microchip lasers are very simple to use without any optical alignment and any maintenance. They foretell a true technical revolution in the domain of solid state lasers which should be opened to high volume and low cost markets. They have many different industrial applications in large markets such as: automotive, laser marking and material processing, environmental and medical applications, public works, telecommunications, etc.

  13. A Continuous-Flow Polymerase Chain Reaction Microchip With Regional Velocity Control

    PubMed Central

    Li, Shifeng; Fozdar, David Y.; Ali, Mehnaaz F.; Li, Hao; Shao, Dongbing; Vykoukal, Daynene M.; Vykoukal, Jody; Floriano, Pierre N.; Olsen, Michael; McDevitt, John T.; Gascoyne, Peter R.C.; Chen, Shaochen

    2009-01-01

    This paper presents a continuous-flow polymerase chain reaction (PCR) microchip with a serpentine microchannel of varying width for “regional velocity control.” Varying the channel width by incorporating expanding and contracting conduits made it possible to control DNA sample velocities for the optimization of the exposure times of the sample to each temperature phase while minimizing the transitional periods during temperature transitions. A finite element analysis (FEA) and semi-analytical heat transfer model was used to determine the distances between the three heating assemblies that are responsible for creating the denaturation (96 °C), hybridization (60 °C), and extension (72 °C) temperature zones within the microchip. Predictions from the thermal FEA and semi-analytical model were compared with temperature measurements obtained from an infrared (IR) camera. Flow-field FEAs were also performed to predict the velocity distributions in the regions of the expanding and contracting conduits to study the effects of the microchannel geometry on flow recirculation and bubble nucleation. The flow fields were empirically studied using micro particle image velocimetry (μ-PIV) to validate the flow-field FEA’s and to determine experimental velocities in each of the regions of different width. Successful amplification of a 90 base pair (bp) bacillus anthracis DNA fragment was achieved. PMID:19829760

  14. A circular ferrofluid driven microchip for rapid polymerase chain reaction.

    PubMed

    Sun, Y; Kwok, Y C; Nguyen, N T

    2007-08-01

    In the past few years, much attention has been paid to the development of miniaturized polymerase chain reaction (PCR) devices. After a continuous flow (CF) PCR chip was introduced, several CFPCR systems employing various pumping mechanisms were reported. However, the use of pumps increases cost and imposes a high requirement on microchip bonding integrity due to the application of high pressure. Other significant limitations of CFPCR devices include the large footprint of the microchip and the fixed cycle number which is dictated by the channel layout. In this paper, we present a novel circular close-loop ferrofluid driven microchip for rapid PCR. A small ferrofluid plug, containing sub-domain magnetic particles in a liquid carrier, is driven by an external magnet along the circular microchannel, which in turn propels the PCR mixture through three temperature zones. Amplification of a 500 bp lambda DNA fragment has been demonstrated on the polymethyl methacrylate (PMMA) PCR microchip fabricated by CO(2) laser ablation and bonded by a low pressure, high temperature technique. Successful PCR was achieved in less than 4 min. Effects of cycle number and cycle time on PCR products were investigated. Using a magnet as the actuator eliminates the need for expensive pumps and provides advantages of low cost, small power consumption, low requirement on bonding strength and flexible number of PCR cycles. Furthermore, the microchip has a much simpler design and smaller footprint compared to the rectangular serpentine CFPCR devices. To demonstrate its application in forensics, a 16-loci short tandem repeat (STR) sample was successfully amplified using the PCR microchip.

  15. MicroChip Imager Module for Recognition of Microorganisms

    SciTech Connect

    Alferov, Oleg

    2001-01-01

    The MicroChip Reader for Cereus Group takes the table of intensities of hybridization signals produced by the MicroChip Imager software and evokes a series of steps designed to recognize the pattern of intensities specific to a particular Cereus subgroup. Seven subgroups of the Cereus group can be identified by particular features of their RNA sequence. The Reader also provides statistics documenting how well its conclusion is confirmed by the hybridization signals. At the user’s request, the Reader can list every recognition step utilized so that the user can verify the recognition process manually if desired.

  16. MicroChip Imager Module for Recognition of Microorganisms

    2001-01-01

    The MicroChip Reader for Cereus Group takes the table of intensities of hybridization signals produced by the MicroChip Imager software and evokes a series of steps designed to recognize the pattern of intensities specific to a particular Cereus subgroup. Seven subgroups of the Cereus group can be identified by particular features of their RNA sequence. The Reader also provides statistics documenting how well its conclusion is confirmed by the hybridization signals. At the user’s request,more » the Reader can list every recognition step utilized so that the user can verify the recognition process manually if desired.« less

  17. Microchip-based electrochemical detection for monitoring cellular systems.

    PubMed

    Johnson, Alicia S; Selimovic, Asmira; Martin, R Scott

    2013-04-01

    The use of microchip devices to study cellular systems is a rapidly growing research area. There are numerous advantages of using on-chip integrated electrodes to monitor various cellular processes. The purpose of this review is to give examples of advancements in microchip-based cellular analysis, specifically where electrochemistry is used for the detection scheme. These examples include on-chip detection of single-cell quantal exocytosis, electrochemical analysis of intracellular contents, the ability to integrate cell culture/immobilization with electrochemistry, and the use of integrated electrodes to ensure cell confluency in longer-term cell culture experiments. A perspective on future trends in this area is also given.

  18. Adding functionality to microchips by wafer post-processing

    NASA Astrophysics Data System (ADS)

    Schmitz, Jurriaan

    2007-06-01

    The traditional microchip processes, stores and communicates electrical information. Here we review an emerging class of microchips that have additional functionality through extra integrated components in the chip. In the final manufacturing stage, layers are added on top of the chip, with a specific property such as sensitivity to ionizing radiation. This paper reviews the technology underlying these monolithic microsystems, including the incorporation of new materials, the unconventional application of photoresist layers, and low-temperature technology for suspended membranes. The manufacturing of exemplary microsystems, such as the active pixel sensor and liquid-crystal-on-silicon, is detailed. A new class of fully integrated radiation imaging systems is now technologically within reach.

  19. Kinetics of hybridization on surface oligonucleotide microchips: theory, experiment, and comparison with hybridization on gel-based microchips.

    PubMed

    Sorokin, N V; Chechetkin, V R; Pan'kov, S V; Somova, O G; Livshits, M A; Donnikov, M Y; Turygin, A Y; Barsky, V E; Zasedatelev, A S

    2006-08-01

    The optimal design of oligonucleotide microchips and efficient discrimination between perfect and mismatch duplexes strongly depend on the external transport of target DNA to the cells with immobilized probes as well as on respective association and dissociation rates at the duplex formation. In this paper we present the relevant theory for hybridization of DNA fragments with oligonucleotide probes immobilized in the cells on flat substrate. With minor modifications, our theory also is applicable to reaction-diffusion hybridization kinetics for the probes immobilized on the surface of microbeads immersed in hybridization solution. The main theoretical predictions are verified with control experiments. Besides that, we compared the characteristics of the surface and gel-based oligonucleotide microchips. The comparison was performed for the chips printed with the same pin robot, for the signals measured with the same devices and processed by the same technique, and for the same hybridization conditions. The sets of probe oligonucleotides and the concentrations of probes in respective solutions used for immobilization on each platform were identical as well. We found that, despite the slower hybridization kinetics, the fluorescence signals and mutation discrimination efficiency appeared to be higher for the gel-based microchips with respect to their surface counterparts even for the relatively short hybridization time about 0.5-1 hour. Both the divergence between signals for perfects and the difference in mutation discrimination efficiency for the counterpart platforms rapidly grow with incubation time. In particular, for hybridization during 3 h the signals for gel-based microchips surpassed their surface counterparts in 5-20 times, while the ratios of signals for perfect-mismatch pairs for gel microchips exceeded the corresponding ratios for surface microchips in 2-4 times. These effects may be attributed to the better immobilization efficiency and to the higher

  20. Portable smartphone optical fibre spectrometer

    NASA Astrophysics Data System (ADS)

    Hossain, Md. Arafat; Canning, John; Cook, Kevin; Jamalipour, Abbas

    2015-09-01

    A low cost, optical fibre based spectrometer has been developed on a smartphone platform for field-portable spectral analysis. Light of visible wavelength is collected using a multimode optical fibre and diffracted by a low cost nanoimprinted diffraction grating. A measurement range over 300 nm span (λ = 400 to 700 nm) is obtained using the smartphone CMOS chip. The spectral resolution is Δλ ~ 0.42 nm/screen pixel. A customized Android application processed the spectra on the same platform and shares with other devices. The results compare well with commercially available spectrometer.

  1. Multiplexed Western Blotting Using Microchip Electrophoresis.

    PubMed

    Jin, Shi; Furtaw, Michael D; Chen, Huaxian; Lamb, Don T; Ferguson, Stephen A; Arvin, Natalie E; Dawod, Mohamed; Kennedy, Robert T

    2016-07-01

    Western blotting is a commonly used protein assay that combines the selectivity of electrophoretic separation and immunoassay. The technique is limited by long time, manual operation with mediocre reproducibility, and large sample consumption, typically 10-20 μg per assay. Western blots are also usually used to measure only one protein per assay with an additional housekeeping protein for normalization. Measurement of multiple proteins is possible; however, it requires stripping membranes of antibody and then reprobing with a second antibody. Miniaturized alternatives to Western blot based on microfluidic or capillary electrophoresis have been developed that enable higher-throughput, automation, and greater mass sensitivity. In one approach, proteins are separated by electrophoresis on a microchip that is dragged along a polyvinylidene fluoride membrane so that as proteins exit the chip they are captured on the membrane for immunoassay. In this work, we improve this method to allow multiplexed protein detection. Multiple injections made from the same sample can be deposited in separate tracks so that each is probed with a different antibody. To further enhance multiplexing capability, the electrophoresis channel dimensions were optimized for resolution while keeping separation and blotting times to less than 8 min. Using a 15 μm deep × 50 μm wide × 8.6 cm long channel, it is possible to achieve baseline resolution of proteins that differ by 5% in molecular weight, e.g., ERK1 (44 kDa) from ERK2 (42 kDa). This resolution allows similar proteins detected by cross-reactive antibodies in a single track. We demonstrate detection of 11 proteins from 9 injections from a single Jurkat cell lysate sample consisting of 400 ng of total protein using this procedure. Thus, multiplexed Western blots are possible without cumbersome stripping and reprobing steps. PMID:27270033

  2. Portable Applications in Mobile Education. Technical Evaluation Report 57

    ERIC Educational Resources Information Center

    Baggaley, Jon

    2006-01-01

    Portable software applications can be carried on a convenient storage medium such as a USB drive, and offer numerous benefits to mobile teachers and learner. The article illustrates the growing field of "portable apps" in reviews of seven contrasting products. These represent the major categories of document editing, email maintenance, Internet…

  3. On-field monitoring of fruit ripening evolution and quality parameters in olive mutants using a portable NIR-AOTF device.

    PubMed

    Cirilli, Marco; Bellincontro, Andrea; Urbani, Stefania; Servili, Maurizio; Esposto, Sonia; Mencarelli, Fabio; Muleo, Rosario

    2016-05-15

    This study optimizes the application of portable Near Infrared-Acousto Optically Tunable Filter (NIR) device to meet the increasing demand for cost-effective, non-invasive and easy-to-use methods for measuring physical and chemical properties during olive fruit development. Fruits from different phenotypically cultivars were sampled for firmness, total and specific phenols detection by HPLC, total anthocyanins, chlorophyll and carotenoids detection by spectrophotometry. On the same fruits, a portable NIR device in diffuse reflectance mode was employed for spectral detections. Predictive models for firmness, chlorophyll, anthocyanins, carotenoids and rutin were developed by Partial Least Square analysis. Oleuropein, verbascoside, 3,4-DHPEA-EDA, and total phenols were used to develop a validation model. Internal cross-validation was applied for calibration and predictive models. The standard errors for calibration, cross-validation, prediction, and RPD ratios (SD/SECV) were calculated as references for the model effectiveness. The determination of the optimal harvesting time facilitates the production of high quality extra virgin olive oil and table olives. PMID:26775949

  4. Human portable preconcentrator system

    DOEpatents

    Linker, Kevin L.; Brusseau, Charles A.; Hannum, David W.; Puissant, James G.; Varley, Nathan R.

    2003-08-12

    A preconcentrator system and apparatus suited to human portable use wherein sample potentially containing a target chemical substance is drawn into a chamber and through a pervious screen. The screen is adapted to capture target chemicals and then, upon heating, to release those chemicals into the chamber. Chemicals captured and then released in this fashion are then carried to a portable chemical detection device such as a portable ion mobility spectrometer. In the preferred embodiment, the means for drawing sample into the chamber comprises a reversible fan which, when operated in reverse direction, creates a backpressure that facilitates evolution of captured target chemicals into the chamber when the screen is heated. The screen can be positioned directly in front of the detector prior to heating to improve detection capability.

  5. A microchip laser with intracavity second-harmonic generation

    SciTech Connect

    Derzhavin, S I; Mashkovskii, D A; Timoshkin, V N

    2008-12-31

    A short-pulse 'green' 532-nm Nd{sup 3+}:YVO{sub 4} and KTiOPO{sub 4} microchip laser with intracavity second-harmonic generation, which is pumped by a 809-nm semiconductor laser diode, is developed. (lasers. amplifiers)

  6. Integrated Micro-Chip Amino Acid Chirality Detector for MOD

    NASA Technical Reports Server (NTRS)

    Glavin, D. P.; Bada, J. L.; Botta, O.; Kminek, G.; Grunthaner, F.; Mathies, R.

    2001-01-01

    Integration of a micro-chip capillary electrophoresis analyzer with a sublimation-based extraction technique, as used in the Mars Organic Detector (MOD), for the in-situ detection of amino acids and their enantiomers on solar system bodies. Additional information is contained in the original extended abstract.

  7. Implantable microchip: the futuristic controlled drug delivery system.

    PubMed

    Sutradhar, Kumar Bishwajit; Sumi, Chandra Datta

    2016-01-01

    There is no doubt that controlled and pulsatile drug delivery system is an important challenge in medicine over the conventional drug delivery system in case of therapeutic efficacy. However, the conventional drug delivery systems often offer a limited by their inability to drug delivery which consists of systemic toxicity, narrow therapeutic window, complex dosing schedule for long term treatment etc. Therefore, there has been a search for the drug delivery system that exhibit broad enhancing activity for more drugs with less complication. More recently, some elegant study has noted that, a new type of micro-electrochemical system or MEMS-based drug delivery systems called microchip has been improved to overcome the problems related to conventional drug delivery. Moreover, micro-fabrication technology has enabled to develop the implantable controlled released microchip devices with improved drug administration and patient compliance. In this article, we have presented an overview of the investigations on the feasibility and application of microchip as an advanced drug delivery system. Commercial manufacturing materials and methods, related other research works and current advancement of the microchips for controlled drug delivery have also been summarized.

  8. Fabrication of PMMA CE microchips by infrared-assisted polymerization.

    PubMed

    Chen, Yun; Duan, Haotian; Zhang, Luyan; Chen, Gang

    2008-12-01

    In this report, a method based on the infrared-assisted polymerization of methyl methacrylate has been developed for the rapid fabrication of PMMA CE microchips. Methyl methacrylate containing AIBN was allowed to prepolymerize in a water bath to form a fast-curing molding solution that was subsequently sandwiched between a silicon template and a piece of 1 mm-thick PMMA plate. The images of microchannels on the silicon template were precisely replicated into the synthesized PMMA substrates during the infrared-assisted polymerization of the molding solution. The polymerization could be completed within 50 min at 50 degrees C. The obtained channel plate was subsequently bonded to a piece of PMMA cover sheet to form a microchip with the aid of heat and pressure. The new fabrication approach obviates the need for special equipment and significantly simplifies the process of fabricating PMMA microchips. The attractive performance of the obtained PMMA microchips has been demonstrated in connection with contactless conductivity detection for the separation and detection of ionic species.

  9. Recent advances in enhancing the sensitivity of electrophoresis and electrochromatography in capillaries and microchips (2012-2014).

    PubMed

    Breadmore, Michael C; Tubaon, Ria Marni; Shallan, Aliaa I; Phung, Sui Ching; Abdul Keyon, Aemi S; Gstoettenmayr, Daniel; Prapatpong, Pornpan; Alhusban, Ala A; Ranjbar, Leila; See, Hong Heng; Dawod, Mohamed; Quirino, Joselito P

    2015-01-01

    One of the most cited limitations of capillary (and microchip) electrophoresis is the poor sensitivity. This review continues to update this series of biannual reviews, first published in Electrophoresis in 2007, on developments in the field of on-line/in-line concentration methods, covering the period July 2012-July 2014. It includes developments in the field of stacking, covering all methods from field-amplified sample stacking and large-volume sample stacking, through to ITP, dynamic pH junction, and sweeping. Attention is also given to on-line or in-line extraction methods that have been used for electrophoresis.

  10. Rapid sample screening method for authenticity controlling vanilla flavors using a CE microchip approach with electrochemical detection.

    PubMed

    Avila, Mónica; González, María Cristina; Zougagh, Mohammed; Escarpa, Alberto; Ríos, Angel

    2007-11-01

    Five vanilla-related flavors of food significance, vanillic alcohol (VOH), ethyl maltol (EMA), maltol (MAL), ethyl vanillin (EVA) and vanillin (VAN), were separated using CE microchips with electrochemical detection (CE-ED microchips). A +2 kV driving voltage for both injection and separation operation steps, using a borate buffer (pH 9.5, 20 mM) and 1 M nitric acid in the detection reservoir allowed the selective and sensitive detection of the target analytes in less than 200 s with reproducible control of EOF (RSD(migration times)<3%). The analysis in selected real vanilla samples was focusing on VAN and EVA because VAN is a basic fragrance compound of the vanilla aroma, whereas EVA is an unequivocal proof of adulteration of vanilla flavors. Fast detection of all relevant flavors (200 s) with an acceptable resolution (R(s) >1.5) and a high accuracy (recoveries higher than 90%) were obtained with independence of the matrices and samples examined. These results showed the reliability of the method and the potential use of CE microchips in the food control field for fraudulent purposes.

  11. Problems Associated with the Microchip Data of Stray Dogs and Cats Entering RSPCA Queensland Shelters.

    PubMed

    Lancaster, Emily; Rand, Jacquie; Collecott, Sheila; Paterson, Mandy

    2015-01-01

    A lack of published information documenting problems with the microchip data for the reclaiming of stray animals entering Australian shelters limits improvement of the current microchipping system. A retrospective study analysing admission data for stray, adult dogs (n = 7258) and cats (n = 6950) entering the Royal Society for the Prevention of Cruelty to Animals (RSPCA) Queensland between January 2012 and December 2013 was undertaken to determine the character and frequency of microchip data problems and their impact on outcome for the animal. Only 28% of dogs and 9% of cats were microchipped, and a substantial proportion (37%) had problems with their data, including being registered to a previous owner or organisation (47%), all phone numbers incorrect/disconnected (29%), and the microchip not registered (14%). A higher proportion of owners could be contacted when the microchip had no problems, compared to those with problems (dogs, 93% vs. 70%; cats, 75% vs. 41%). The proportion of animals reclaimed declined significantly between microchipped animals with no data problems, microchipped animals with data problems and non-microchipped animals-87%, 69%, and 37%, respectively, for dogs and 61%, 33%, and 5%, respectively, for cats. Strategies are needed to increase the accuracy of microchip data to facilitate the reclaiming of stray dogs and cats.

  12. Comparing polyelectrolyte multilayer - coated poly(methylmethacrylate) microfluidic devices and glass microchips for electrophoretic separations

    PubMed Central

    Currie, Christa A.; Shim, Joon Sub; Ahn, Chong; Limbach, Patrick A.; Halsall, H. Brian

    2010-01-01

    There is a continuing drive in microfluidics to transfer microchip systems from the more expensive glass microchips to cheaper polymer microchips. Here, we investigate using polyelectrolyte multilayers (PEM) as a coating system for poly (methylmethacrylate) (PMMA) microchips to improve their functionality. The multilayer system was prepared by layer-on-layer depositon of poly (diallydimethylammonium) chloride (PDAD) and polystyrene sulfonate (PSS). Practical aspects of coating PMMA microchips were explored. The multilayer buildup process was monitored using EOF measurements, and the stability of the PEM was investigated. The performance of the PEM-PMMA microchip was compared to those of a standard glass microchip and a PEM-glass microchip in terms of electroosmotic flow and separating two fluorescent dyes. Several key findings in the development of the multilayer coating procedure for PMMA chips are also presented. It was found that, with careful preparation, a PEM-PMMA microchip can be prepared that has properties comparable - and in some cases superior - to those of a standard glass microchip. PMID:20013912

  13. Comparing polyelectrolyte multilayer-coated PMMA microfluidic devices and glass microchips for electrophoretic separations.

    PubMed

    Currie, Christa A; Shim, Joon Sub; Lee, Se Hwan; Ahn, Chong; Limbach, Patrick A; Halsall, H Brian; Heineman, William R

    2009-12-01

    There is a continuing drive in microfluidics to transfer microchip systems from the more expensive glass microchips to cheaper polymer microchips. Here, we investigate using polyelectrolyte multilayers (PEM) as a coating system for PMMA microchips to improve their functionality. The multilayer system was prepared by layer-to-layer deposition of poly(diallyldimethylammonium) chloride and polystyrene sulfonate. Practical aspects of coating PMMA microchips were explored. The multilayer buildup process was monitored using EOF measurements, and the stability of the PEM was investigated. The performance of the PEM-PMMA microchip was compared with those of a standard glass microchip and a PEM-glass microchip in terms of EOF and separating two fluorescent dyes. Several key findings in the development of the multilayer coating procedure for PMMA chips are also presented. It was found that, with careful preparation, a PEM-PMMA microchip can be prepared that has properties comparable--and in some cases superior--to those of a standard glass microchip.

  14. Problems Associated with the Microchip Data of Stray Dogs and Cats Entering RSPCA Queensland Shelters.

    PubMed

    Lancaster, Emily; Rand, Jacquie; Collecott, Sheila; Paterson, Mandy

    2015-01-01

    A lack of published information documenting problems with the microchip data for the reclaiming of stray animals entering Australian shelters limits improvement of the current microchipping system. A retrospective study analysing admission data for stray, adult dogs (n = 7258) and cats (n = 6950) entering the Royal Society for the Prevention of Cruelty to Animals (RSPCA) Queensland between January 2012 and December 2013 was undertaken to determine the character and frequency of microchip data problems and their impact on outcome for the animal. Only 28% of dogs and 9% of cats were microchipped, and a substantial proportion (37%) had problems with their data, including being registered to a previous owner or organisation (47%), all phone numbers incorrect/disconnected (29%), and the microchip not registered (14%). A higher proportion of owners could be contacted when the microchip had no problems, compared to those with problems (dogs, 93% vs. 70%; cats, 75% vs. 41%). The proportion of animals reclaimed declined significantly between microchipped animals with no data problems, microchipped animals with data problems and non-microchipped animals-87%, 69%, and 37%, respectively, for dogs and 61%, 33%, and 5%, respectively, for cats. Strategies are needed to increase the accuracy of microchip data to facilitate the reclaiming of stray dogs and cats. PMID:26479238

  15. Portable alpha spectrometer.

    PubMed

    Martín Sánchez, A; de la Torre Pérez, J

    2012-09-01

    Many portable devices have been designed to detect γ-rays or alpha and beta particles. Most of the α-particle detectors give the total count as a result, without identifying the radionuclides existing in the sample. The development of a device allowing rapid and straightforward α-particle spectrometry would be very useful for detecting the radioactive contents of unknown samples. This work describes the construction of a portable device using silicon semiconductor detectors designed to rapidly detect and possibly identify alpha-emitting radionuclides.

  16. Portable humanitarian mine detector overview

    NASA Astrophysics Data System (ADS)

    Allsopp, David J.; Dibsdall, Ian M.

    2002-08-01

    This paper will present an overview and early results of the QinetiQ Portable Humanitarian Mine Detector project, funded by the UK Treasury Capital Modernization Fund. The project aims to develop a prototype multi-sensor man-portable detector for humanitarian demining, drawing on experience from work for UK MoD. The project runs from July 2000 to October 2002. The project team have visited mined areas and worked closely with a number of demining organizations and a manufacturer of metal detectors used in the field. The primary objective is to reduce the number of false alarms resulting from metallic ground clutter. An analysis of such clutter items found during actual demining has shown a large proportion to be very small when compared with anti-personnel mines. The planned system integrates: a lightweight multi-element pseudo-random-code ground penetrating radar array; a pulse induction metal detector and a capacitive sensor. Data from the GPR array and metal detector are fused to provide a simple audio-visual operator interface. The capacitive sensor provides information to aid processing of the radar responses and to provide feedback to the operator of the position of the sensors above the ground. At the time of presentation the project should be in the final stages of build, prior to tests and field trials, which QinetiQ hope to carry out under the International Test and Evaluation Project (ITEP) banner.

  17. Dual-electrode electrochemical detection for poly(dimethylsiloxane)-fabricated capillary electrophoresis microchips.

    PubMed

    Martin, R S; Gawron, A J; Lunte, S M

    2000-07-15

    The development of a poly(dimethylsiloxane)-based (PDMS-based) microchip electrophoresis system employing dual-electrode electrochemical detection is described. This is the first report of dual-electrode electrochemical detection in a microchip format and of electrochemical detection on chips fabricated from PDMS. The device described in this paper consists of a top layer of PDMS containing the separation and injection channels and a bottom glass layer onto which gold detection electrodes have been deposited. The two layers form a tight reversible seal, eliminating the need for high-temperature bonding, which can be detrimental to electrode stability. The channels can also be temporarily removed for cleaning, significantly extending the lifetime of the chip. The performance of the chip was evaluated using catechol as a test compound. The response was linear from 10 to 500 microM with an LOD (S/N = 3) of 4 microM and a sensitivity of 45.9 pA/microM. Collection efficiencies for catechol ranged from 28.7 to 25.9% at field strengths between 200 and 400 V/cm. Dual-electrode detection in the series configuration was shown to be useful for the selective monitoring of species undergoing chemically reversible redox reactions and for peak identification in the electropherogram of an unresolved mixture.

  18. Flow-through cell electroporation microchip integrating dielectrophoretic viable cell sorting.

    PubMed

    Wei, Zewen; Li, Xueming; Zhao, Deyao; Yan, Hao; Hu, Zhiyuan; Liang, Zicai; Li, Zhihong

    2014-10-21

    Microfluidics based continuous cell electroporation is an appealing approach for high-throughput cell transfection, but cell viability of existing methods is usually compromised by adverse electrical or hydrodynamic effects. Here we present the validation of a flow-through cell electroporation microchip, in which dielectrophoretic force was employed to sort viable cells. By integrating parallel electroporation electrodes and dielectrophoresis sorting electrodes together in a simple straight microfluidic channel, sufficient electrical pulses were applied for efficient electroporation, and a proper sinusoidal electrical field was subsequently utilized to exclude damaged cells by dielectrophoresis. Thus, the difficulties for seeking the fine balance between electrotransfection efficiency and cell viability were steered clear. After careful investigation and optimization of the DEP behaviors of electroporated cells, efficient electrotransfection of plasmid DNA was demonstrated in vulnerable neuron cells and several hard-to-transfect primary cell types with excellent cell viability. This microchip constitutes a novel way of continuous cell transfection to significantly improve the cell viability of existing methodologies.

  19. Occupational safety and health implications of the millennium bug: embedded microchips.

    PubMed

    Anderson, V P

    1999-06-01

    Personnel working in the field of environmental safety and health need to be aware that their exposure monitoring equipment as well as various laboratory and work site test and safety systems are candidates for a Y2K problem. The focus here is on the Y2K problem associated with embedded microchips contained in measurement and analytical equipment with internal date functions. With the turn of the century, the year 99 (i.e., 1999) will turn to 00 (i.e., 2000). The expectation is that the date change over will result in some form of malfunction or failure. The media has provided us with basic information on Y2K, particularly as it impacts computer hardware and software users. We know less, however, about how the Y2K issue may affect date-sensitive embedded microchips in safety and health equipment. To manage this problem, we propose a familiar public health strategy involving risk assessment (surveillance and prioritizing) and risk management (intervention/contingency planning). Success in dealing with Y2K-embedded chips will be increased by engaging managers, operators, employee-management safety teams, safety professionals and their organizations, trade associations, local, state and federal regulatory agencies, and the public, where appropriate. A list of Internet sites is provided with information on managing problems arising from date-dependent embedded chips and the Y2K problem. PMID:10429729

  20. Portable Data Logger for Photovoltaic Panels

    NASA Technical Reports Server (NTRS)

    Cole, S. W.

    1983-01-01

    Instrument measures rapidly changing knee of V-I curve with extra care. Portable data logger runs on own batteries. Includes microcomputer, which controls voltage-, current-measurement increment, and solid state memory, which stores data until transferred to EPROM module. Data logger is light, compact and easily caried to remote field locations.

  1. Polycyclic aromatic hydrocarbon analysis with the Mars organic analyzer microchip capillary electrophoresis system.

    PubMed

    Stockton, Amanda M; Chiesl, Thomas N; Scherer, James R; Mathies, Richard A

    2009-01-15

    The Mars Organic Analyzer (MOA), a portable microchip capillary electrophoresis (CE) instrument developed for sensitive amino acid analysis on Mars, is used to analyze laboratory standards and real-world samples for polycyclic aromatic hydrocarbons (PAHs). The microfabricated CE separation and analysis method for these hydrophobic analytes is optimized, resulting in a separation buffer consisting of 10 mM sulfobutylether-beta-cyclodextrin, 40 mM methyl-beta-cyclodextrin, 5 mM carbonate buffer at pH 10, 5 degrees C. A PAH standard consisting of seven PAHs found in extraterrestrial matter and two terrestrial PAHs is successfully baseline separated. Limits of detection for the components of the standard ranged from 2000 ppm to 6 ppb. Analysis of an environmental contamination standard from Lake Erie and of a hydrothermal vent chimney sample from the Guaymas Basin agreed with published composition. A Martian analogue sample from the Yungay Hills region of the Atacama Desert was analyzed and found to contain 9,10-diphenylanthracene, anthracene, anthanthrene, fluoranthene, perylene, and benzo[ghi]fluoranthene at ppm levels. This work establishes the viability of the MOA for detecting and analyzing PAHs in in situ planetary exploration.

  2. Fixed Facts about Portable Classrooms.

    ERIC Educational Resources Information Center

    Sturgeon, Julie

    1998-01-01

    Discusses the easing of overcrowded schools through the use of portable classrooms and provides an example from Elk Grove Unified School District (California) which has opened entire elementary schools using only portables. Fifteen tips for installing relocatables are highlighted. (GR)

  3. Portable nanoparticle based sensors for antioxidant analysis.

    PubMed

    Sharpe, Erica; Andreescu, Silvana

    2015-01-01

    Interest in portable sensing devices has increased throughout the past decade. Portable sensors are convenient for use in remote locations and in places with limited resources for advanced instrumentation. Often such devices utilize advanced technology that allows the final user to simply deposit the sample onto the sensing platform without preparation of multiple reagents. Herein, we describe preparation and characterization of a colorimetric paper-based metal oxide sensing array designed for the field detection of polyphenolic antioxidants. This sensor is a good candidate for use in analysis of the antioxidant character of food, drink, botanical medicines, physiological fluids, and more. PMID:25323510

  4. Portable Aerosol Contaminant Extractor

    DOEpatents

    Carlson, Duane C.; DeGange, John J.; Cable-Dunlap, Paula

    2005-11-15

    A compact, portable, aerosol contaminant extractor having ionization and collection sections through which ambient air may be drawn at a nominal rate so that aerosol particles ionized in the ionization section may be collected on charged plate in the collection section, the charged plate being readily removed for analyses of the particles collected thereon.

  5. Portable Weld Tester.

    ERIC Educational Resources Information Center

    Eckert, Douglas

    This training manual, which was developed for employees of an automotive plant, is designed to teach trainees to operate a portable weld tester (Miyachi MM-315). In chapter 1, the weld tester's components are illustrated and described, and the procedure for charging its batteries is explained. Chapter 2 illustrates the weld tester's parts,…

  6. Mobility, Portability, and Placelessness

    ERIC Educational Resources Information Center

    Kupfer, Joseph

    2007-01-01

    Electronic technology has created a revolution in portability of information, documentation, and communication. We are now able to connect with people, information, organizations, and merchandise from anywhere at practically any time. As electronically fabricated environments replace actual physical surroundings, however, we become displaced.…

  7. Portable Lifting Seat

    NASA Technical Reports Server (NTRS)

    Weddendorf, Bruce

    1993-01-01

    Portable lifting machine assists user in rising from seated position to standing position, or in sitting down. Small and light enough to be carried like briefcase. Used on variety of chairs and benches. Upholstered aluminum box houses mechanism of lifting seat. Springs on outer shaft-and-arm subassembly counterbalance part of user's weight to assist motor.

  8. PORTABLE SOURCE OF RADIOACTIVITY

    DOEpatents

    Goertz, R.C.; Ferguson, K.R.; Rylander, E.W.; Safranski, L.M.

    1959-06-16

    A portable source for radiogiaphy or radiotherapy is described. It consists of a Tl/sup 170/ or Co/sup 60/ source mounted in a rotatable tungsten alloy plug. The plug rotates within a brass body to positions of safety or exposure. Provision is made for reloading and carrying the device safely. (T.R.H.)

  9. Portable oven air circulator

    DOEpatents

    Jorgensen, Jorgen A.; Nygren, Donald W.

    1983-01-01

    A portable air circulating apparatus for use in cooking ovens which is used to create air currents in the oven which transfer heat to cooking foodstuffs to promote more rapid and more uniform cooking or baking, the apparatus including a motor, fan blade and housing of metallic materials selected from a class of heat resistant materials.

  10. Portable dynamic fundus instrument

    NASA Technical Reports Server (NTRS)

    Taylor, Gerald R. (Inventor); Meehan, Richard T. (Inventor); Hunter, Norwood R. (Inventor); Caputo, Michael P. (Inventor); Gibson, C. Robert (Inventor)

    1992-01-01

    A portable diagnostic image analysis instrument is disclosed for retinal funduscopy in which an eye fundus image is optically processed by a lens system to a charge coupled device (CCD) which produces recordable and viewable output data and is simultaneously viewable on an electronic view finder. The fundus image is processed to develop a representation of the vessel or vessels from the output data.

  11. Portable Suction Lysimeter

    DOEpatents

    Hubbell, Joel M.; Sisson, James B.

    2004-07-13

    A portable lysimeter including a collection vessel having an inflatable bladder and a semi-permeable member assembly at least partially movable in response to inflation of the bladder, a sample conduit in fluid communication with the semi-permeable member and a reservoir in fluid communication with the sample conduit.

  12. Portable sensor for hazardous waste

    SciTech Connect

    Piper, L.G.; Hunter, A.J.R.; Fraser, M.E.; Davis, S.J.

    1996-12-31

    We are part-way through the second phase of a 4-year program designed to develop a portable monitor for sensitive hazardous waste detection. The ultimate goal of the program is to develop our concept to the prototype instrument level. Our monitor will be a compact, portable instrument that will allow real-time, in situ, monitoring of hazardous wastes. This instrument will be able to provide the means for rapid field screening of hazardous waste sites to map the areas of greatest contamination. Remediation efforts can then focus on these areas. Our analysis approach is to excite atomic and molecular fluorescence by the technique of active nitrogen energy transfer (ANET). The active nitrogen is made in a dielectric-barrier (D-B) discharge in nitrogen at atmospheric pressure. Only a few emission lines or bands are excited for each hazardous species, so spectral resolution requirements are greatly simplified over those of other spectroscopic techniques. The D-B discharge is compact, 1 to 2 cm in diameter and 1 to 10 cm long. Furthermore, the discharge power requirements are quite modest, so that the unit can be powered by batteries. Thus an instrument based on ANET can readily be made portable. Our results indicate that ANET is a very sensitive technique for monitoring heavy metals and chlorinated hydrocarbons. We have demonstrated an overall detection sensitivity for most species that is at or below ppb levels. ANET alone, however, appears to be most successful in treating hazardous species that have been atomized. We are therefore developing a hybrid technique which combines a miniature, solid-state laser for sample collection and vaporization with ANET for subsequent detection. This approach requires no special sample preparation, can operate continuously, and lends itself well to compact packaging.

  13. Hand-portable liquid chromatographic instrumentation.

    PubMed

    Sharma, Sonika; Tolley, Luke T; Tolley, H Dennis; Plistil, Alex; Stearns, Stanley D; Lee, Milton L

    2015-11-20

    Over the last four decades, liquid chromatography (LC) has experienced an evolution to smaller columns and particles, new stationary phases and low flow rate instrumentation. However, the development of person-portable LC has not followed, mainly due to difficulties encountered in miniaturizing pumps and detectors, and in reducing solvent consumption. The recent introduction of small, non-splitting pumping systems and UV-absorption detectors for use with capillary columns has finally provided miniaturized instrumentation suitable for high-performance hand-portable LC. Fully integrated microfabricated LC still remains a significant challenge. Ion chromatography (IC) has been successfully miniaturized and applied for field analysis; however, applications are mostly limited to inorganic and small organic ions. This review covers advancements that make possible more rapid expansion of portable forms of LC and IC.

  14. Portable outgas detection apparatus

    SciTech Connect

    Haney, Steven Julian; Malinowski, Michael E.

    2004-05-11

    A portable device for detecting surface outgas contaminants of an article includes: (i) a portable housing that has a chamber which is in communication with a port that is adapted to be sealably attached to a surface of the article; (ii) a mass spectrometer that is coupled to the chamber for analyzing gaseous materials in the chamber; and (iii) means for generating a vacuum within the chamber thereby drawing outgas contaminants from the surface of the article into the chamber for analysis by the mass spectrometer. By performing a mass spectrometric analysis of the surface of interest and comparing the data with mass spectrometric data ascertained with the device from a clean surface, the type and amount of outgas contaminants, if any, can be determined.

  15. Field measurements of biogenic volatile organic compounds in the atmosphere by dynamic solid-phase microextraction and portable gas chromatography-mass spectrometry

    NASA Astrophysics Data System (ADS)

    Barreira, Luís Miguel Feijó; Parshintsev, Jevgeni; Kärkkäinen, Niina; Hartonen, Kari; Jussila, Matti; Kajos, Maija; Kulmala, Markku; Riekkola, Marja-Liisa

    2015-08-01

    Biogenic volatile organic compounds (BVOCs) participate in many physicochemical processes in the atmosphere. Studies indicate that some of these volatile compounds can be photo-oxidized to non-volatile species that contribute to atmospheric formation and growth of secondary organic aerosols (SOA). In this study, the applicability of dynamic solid-phase microextraction (SPME) for the sampling of atmospheric BVOCs and their oxidation products was tested. These compounds were then analysed via portable gas chromatography-mass spectrometry (GC-MS). The measurements were performed in mid-summer 2013 at the Station for Measuring Ecosystem-Atmosphere Relations, SMEAR II in Hyytiälä, Finland. Numerous classes of compounds were efficiently sampled on PDMS/DVB coated SPME, thermally desorbed and analysed by GC-MS, including monoterpenes, their oxidation products, and amines. Results were analysed against meteorological conditions observed during the sampling campaign and the total amount of monoterpenes obtained by proton-transfer-reaction mass spectrometry (PTR-MS). The comparison of the referred data with obtained results demonstrated the capability of the dynamic SPME method for fast in-situ sampling and analysis of organic gaseous compounds in the atmosphere with minimal analytical steps.

  16. Portable Spray Booth

    NASA Technical Reports Server (NTRS)

    Hansen, Timothy D.; Bardwell, Micheal J.

    1996-01-01

    Portable spray booth provides for controlled application of coating materials with high solvent contents. Includes contoured shroud and carbon filter bed limiting concentration of fumes in vicinity. Designed to substitute spraying for brush application of solvent-based adhesive prior to installing rubber waterproof seals over joints between segments of solid-fuel rocket motor. With minor adjustments and modifications, used to apply other solvent-based adhesives, paints, and like.

  17. Portable Planetariums Teach Science

    NASA Technical Reports Server (NTRS)

    2015-01-01

    With the Internet proving to be the wave of the future, in the 1990s Johnson Space Center awarded grants to Rice University in Houston for developing the world's first Internet-accessible museum kiosk. Further grants were awarded to the school for creating educational software for use in homes and schools, leading to the creation of Museums Teaching Planet Earth Inc. The company has gone on to develop and sell portable planetariums and accompanying educational shows.

  18. Portable Laser Laboratory

    SciTech Connect

    Weir, J.T.

    1994-07-01

    A Portable Laser Laboratory (PLL) is being designed and built for the CALIOPE Program tests which will begin in October of 1994. The PLL is designed to give maximum flexibility for evolving laser experiments and can be readily moved by loading it onto a standard truck trailer. The internal configuration for the October experiments will support a two line DIAL system running in the mid-IR. Brief descriptions of the laser and detection systems are included.

  19. Portable cutting apparatus

    DOEpatents

    Gilmore, R.F.

    1984-07-17

    A remotely operable, portable cutting apparatus detachably secured to the workpiece by laterally spaced clamp assemblies engagable with the workpiece on opposite sides of the intended line of cut. A reciprocal cutter head is mounted between the clamp assemblies and is provided with a traveling abrasive cutting wire adapted to sever the workpiece normal to the longitudinal axis thereof. Dust and debris are withdrawn from the cutting area by a vacuum force through a nozzle mounted on the cutting head.

  20. Microchip capillary electrophoresis of nitrite and nitrate in cerebrospinal fluid.

    PubMed

    Masár, Marián; Bodor, Róbert; Troška, Peter

    2015-01-01

    Microchip capillary electrophoresis (MCE) is a relatively new analytical method requiring only small sample amounts, which is very favorable for the analysis of volume-limited biofluids. The practical use of MCE in bioanalysis is still restricted in terms of requirements for simplifying and/or concentrating sample pretreatment techniques. Here, we describe an MCE method for trace analysis of nitrite and nitrate, indicators of various neurological diseases, in cerebrospinal fluid (CSF). The complex CSF samples were simplified by solid-phase microextraction prior to an online combination of isotachophoresis with capillary zone electrophoresis performed on a microchip with coupled channels and a high-volume sample injection channel (9.9 μL). The method is suitable for rapid (total analysis time lasted 20 min), reproducible (0.6-2.4 % RSD for migration time), and sensitive (3-9 nM limits of detection) determinations of nitrite and nitrate in 15-50 times diluted CSF samples. PMID:25673480

  1. Microchip-based electrochemical detection for monitoring cellular systems

    PubMed Central

    Johnson, Alicia S.; Selimovic, Asmira; Martin, R. Scott

    2013-01-01

    The use of microchip devices to study cellular systems is a rapidly growing research area. There are numerous advantages of using on-chip integrated electrodes to monitor various cellular processes. The purpose of this review article is to give examples of advancements in microchip-based cellular analysis, specifically where electrochemistry is used for the detection scheme. These examples include on-chip detection of single cell quantal exocytosis, electrochemical analysis of intracellular contents, the ability to integrate cell culture/immobilization with electrochemistry, and the use of integrated electrodes to ensure cell confluency in longer term cell culture experiments. A perspective on future trends in this area is also given. PMID:23340999

  2. Design and Fabrication of a PDMS Microchip Based Immunoassay

    SciTech Connect

    Shao, Guocheng; Wang, Wanjun; Wang, Jun; Lin, Yuehe

    2010-07-01

    In this paper, we describe the design and fabrication process of a polydimethylsiloxane (PDMS) microchip for on-chip multiplex immunoassay application. The microchip consists of a PDMS microfluidic channel layer and a micro pneumatic valve control layer. By selectively pressurizing the pneumatic microvalves, immuno reagents were controlled to flow and react in certain fluidic channel sites. Cross contamination was prevented by tightly closed valves. Our design was proposed to utilize PDMS micro channel surface as the solid phase immunoassay substrate and simultaneously detect four targets antigens on chip. Experiment result shows that 20psi valve pressure is sufficient to tightly close a 200µm wide micro channel with flow rate up to 20µl/min.

  3. Microchip-based detection of magnetically labeled cancer biomarkers.

    PubMed

    Muluneh, Melaku; Issadore, David

    2014-02-01

    Micro-magnetic sensing and actuation have emerged as powerful tools for the diagnosis and monitoring of cancer. These technologies can be miniaturized and integrated onto compact, microfluidic platforms, enabling molecular diagnostics to be performed in practical clinical settings. Molecular targets tagged with magnetic nanoparticles can be detected with high sensitivity directly in unprocessed clinical samples (e.g. blood, sputum) due to the inherently negligible magnetic susceptibility of biological material. As a result, magnetic microchip-based diagnostics have been applied with great success to the isolation and detection of rare cells and the measurement of sparse soluble proteins. In this paper, we review recent advances in microchip-based detection of magnetically labeled biomarkers and their translation to clinical applications in cancer.

  4. Microchip capillary electrophoresis of nitrite and nitrate in cerebrospinal fluid.

    PubMed

    Masár, Marián; Bodor, Róbert; Troška, Peter

    2015-01-01

    Microchip capillary electrophoresis (MCE) is a relatively new analytical method requiring only small sample amounts, which is very favorable for the analysis of volume-limited biofluids. The practical use of MCE in bioanalysis is still restricted in terms of requirements for simplifying and/or concentrating sample pretreatment techniques. Here, we describe an MCE method for trace analysis of nitrite and nitrate, indicators of various neurological diseases, in cerebrospinal fluid (CSF). The complex CSF samples were simplified by solid-phase microextraction prior to an online combination of isotachophoresis with capillary zone electrophoresis performed on a microchip with coupled channels and a high-volume sample injection channel (9.9 μL). The method is suitable for rapid (total analysis time lasted 20 min), reproducible (0.6-2.4 % RSD for migration time), and sensitive (3-9 nM limits of detection) determinations of nitrite and nitrate in 15-50 times diluted CSF samples.

  5. Diode edge-pumped passively Q-switched microchip laser

    NASA Astrophysics Data System (ADS)

    Kong, Weipeng; Tsunekane, Masaki; Taira, Takunori

    2015-09-01

    There is an increasing demand for high-intensity subnanosecond lasers for emerging industrial applications. While femtosecond and picosecond laser sources are considered promising, they suffer from the significant drawbacks of increased complexity and cost. In this regard, we demonstrate a unique edge-pumped passively Q-switched Nd∶YAG/Cr4+∶YAG microchip laser. The microchip is made of a Nd∶YAG/Sm∶YAG composite ceramic, and a Sm∶YAG cladding is utilized as both the pump beam waveguide and amplified spontaneous emission absorber. With the use of a flat-concave laser cavity, we obtain single-pulse energy of 1.66 mJ for an absorbed pump energy of 24 mJ. Further, the resulting pulse width is 683 ps, and the repetition rate is 10 Hz.

  6. Military display market segment: wearable and portable

    NASA Astrophysics Data System (ADS)

    Desjardins, Daniel D.; Hopper, Darrel G.

    2003-09-01

    The military display market (MDM) is analyzed in terms of one of its segments, wearable and portable displays. Wearable and portable displays are those embedded in gear worn or carried by warfighters. Categories include hand-mobile (direct-view and monocular/binocular), palm-held, head/helmet-mounted, body-strapped, knee-attached, lap-born, neck-lanyard, and pocket/backpack-stowed. Some 62 fielded and developmental display sizes are identified in this wearable/portable MDM segment. Parameters requiring special consideration, such as weight, luminance ranges, light emission, viewing angles, and chromaticity coordinates, are summarized and compared. Ruggedized commercial versus commercial off-the-shelf designs are contrasted; and a number of custom displays are also found in this MDM category. Display sizes having aggregate quantities of 5,000 units or greater or having 2 or more program applications are identified. Wearable and portable displays are also analyzed by technology (LCD, LED, CRT, OLED and plasma). The technical specifications and program history of several high-profile military programs are discussed to provide a systems context for some representative displays and their function. As of August 2002 our defense-wide military display market study has documented 438,882 total display units distributed across 1,163 display sizes and 438 weapon systems. Wearable and portable displays account for 202,593 displays (46% of total DoD) yet comprise just 62 sizes (5% of total DoD) in 120 weapons systems (27% of total DoD). Some 66% of these wearable and portable applications involve low information content displays comprising just a few characters in one color; however, there is an accelerating trend towards higher information content units capable of showing changeable graphics, color and video.

  7. Continuous two-wave lasing in microchip Nd : YAG lasers

    SciTech Connect

    Ievlev, Ivan V; Koryukin, Igor' V; Lebedeva, Yu S; Khandokhin, Pavel A

    2011-08-31

    Simultaneous two-wave lasing was obtained in microchip end-pumped Nd:YAG lasers at the wavelengths of 1061.5 and 1064.17 nm at room temperature. Laser wave intensities were studied as functions of crystal temperature and pump power. The ranges of parameters were determined in which the two-wave lasing occurs and the reasons for such lasing were established. A model is suggested, which adequately describes the experimental results obtained. (control of radiation parameters)

  8. Large linewidth-enhancement factor in a microchip laser

    SciTech Connect

    Szwaj, Christophe; Lacot, Eric; Hugon, Olivier

    2004-09-01

    We evidence experimentally that the linewidth-enhancement factor {alpha} can take a rather large value ({alpha}{approx_equal}1) for a nonsemiconductor laser, here a Nd{sup 3+}: YAG microchip laser. This measure is performed using an original and simple method adapted to this kind of laser and based on the variations of the laser relaxation frequency when the laser is subjected to an optical feedback.

  9. A minimally invasive microchip for transdermal injection/sampling applications.

    PubMed

    Strambini, Lucanos M; Longo, Angela; Diligenti, Alessandro; Barillaro, Giuseppe

    2012-09-21

    The design, fabrication, and characterization of a minimally invasive silicon microchip for transdermal injection/sampling applications are reported and discussed. The microchip exploits an array of silicon-dioxide hollow microneedles with density of one million needles cm(-2) and lateral size of a few micrometers, protruding from the front-side chip surface for one hundred micrometers, to inject/draw fluids into/from the skin. The microneedles are in connection with independent reservoirs grooved on the back-side of the chip. Insertion experiments of the microchip in skin-like polymers (agarose hydrogels with concentrations of 2% and 4% wt) demonstrate that the microneedles successfully withstand penetration without breaking, despite their high density and small size, according to theoretical predictions. Operation of the microchip with different liquids of biomedical interest (deionized water, NaCl solution, and d-glucose solution) at different differential pressures, in the range 10-100 kPa, highlights that the flow-rate through the microneedles is linearly dependent on the pressure-drop, despite the small section area (about 13 μm(2)) of the microneedle bore, and can be finely controlled from a few ml min(-1) up to tens of ml min(-1). Evaporation (at room temperature) and acceleration (up to 80 g) losses through the microneedles are also investigated to quantify the ability of the chip in storing liquids (drug to be delivered or collected fluid) in the reservoir, and result to be of the order of 70 nl min(-1) and 1300 nl min(-1), respectively, at atmospheric pressure and room temperature. PMID:22773092

  10. A minimally invasive microchip for transdermal injection/sampling applications.

    PubMed

    Strambini, Lucanos M; Longo, Angela; Diligenti, Alessandro; Barillaro, Giuseppe

    2012-09-21

    The design, fabrication, and characterization of a minimally invasive silicon microchip for transdermal injection/sampling applications are reported and discussed. The microchip exploits an array of silicon-dioxide hollow microneedles with density of one million needles cm(-2) and lateral size of a few micrometers, protruding from the front-side chip surface for one hundred micrometers, to inject/draw fluids into/from the skin. The microneedles are in connection with independent reservoirs grooved on the back-side of the chip. Insertion experiments of the microchip in skin-like polymers (agarose hydrogels with concentrations of 2% and 4% wt) demonstrate that the microneedles successfully withstand penetration without breaking, despite their high density and small size, according to theoretical predictions. Operation of the microchip with different liquids of biomedical interest (deionized water, NaCl solution, and d-glucose solution) at different differential pressures, in the range 10-100 kPa, highlights that the flow-rate through the microneedles is linearly dependent on the pressure-drop, despite the small section area (about 13 μm(2)) of the microneedle bore, and can be finely controlled from a few ml min(-1) up to tens of ml min(-1). Evaporation (at room temperature) and acceleration (up to 80 g) losses through the microneedles are also investigated to quantify the ability of the chip in storing liquids (drug to be delivered or collected fluid) in the reservoir, and result to be of the order of 70 nl min(-1) and 1300 nl min(-1), respectively, at atmospheric pressure and room temperature.

  11. Solid-state detector and optical system for microchip analyzers

    DOEpatents

    Mathies, Richard A.; Kamei, Toshihiro; Scherer, James R.; Street, Robert A.

    2005-03-15

    A miniaturized optical excitation and detector system is described for detecting fluorescently labeled analytes in electrophoretic microchips and microarrays. The system uses miniature integrated components, light collection, optical fluorescence filtering, and an amorphous a-Si:H detector for detection. The collection of light is accomplished with proximity gathering and/or a micro-lens system. Optical filtering is accomplished by integrated optical filters. Detection is accomplished utilizing a-Si:H detectors.

  12. Axial thermal gradients in microchip gas chromatography.

    PubMed

    Wang, Anzi; Hynynen, Sampo; Hawkins, Aaron R; Tolley, Samuel E; Tolley, H Dennis; Lee, Milton L

    2014-12-29

    Fabrication technologies for microelectromechanical systems (MEMS) allow miniaturization of conventional benchtop gas chromatography (GC) to portable, palm-sized microfabricated GC (μGC) devices, which are suitable for on-site chemical analysis and remote sensing. The separation performance of μGC systems, however, has not been on par with conventional GC. Column efficiency, peak symmetry and resolution are often compromised by column defects and non-ideal injections. The relatively low performance of μGC devices has impeded their further commercialization and broader application. In this work, the separation performance of μGC columns was improved by incorporating thermal gradient gas chromatography (TGGC). The analysis time was ∼20% shorter for TGGC separations compared to conventional temperature-programmed GC (TPGC) when a wide sample band was introduced into the column. Up to 50% reduction in peak tailing was observed for polar analytes, which improved their resolution. The signal-to-noise ratios (S/N) of late-eluting peaks were increased by 3-4 fold. The unique focusing effect of TGGC overcomes many of the previous shortcomings inherent in μGC analyses.

  13. Axial thermal gradients in microchip gas chromatography.

    PubMed

    Wang, Anzi; Hynynen, Sampo; Hawkins, Aaron R; Tolley, Samuel E; Tolley, H Dennis; Lee, Milton L

    2014-12-29

    Fabrication technologies for microelectromechanical systems (MEMS) allow miniaturization of conventional benchtop gas chromatography (GC) to portable, palm-sized microfabricated GC (μGC) devices, which are suitable for on-site chemical analysis and remote sensing. The separation performance of μGC systems, however, has not been on par with conventional GC. Column efficiency, peak symmetry and resolution are often compromised by column defects and non-ideal injections. The relatively low performance of μGC devices has impeded their further commercialization and broader application. In this work, the separation performance of μGC columns was improved by incorporating thermal gradient gas chromatography (TGGC). The analysis time was ∼20% shorter for TGGC separations compared to conventional temperature-programmed GC (TPGC) when a wide sample band was introduced into the column. Up to 50% reduction in peak tailing was observed for polar analytes, which improved their resolution. The signal-to-noise ratios (S/N) of late-eluting peaks were increased by 3-4 fold. The unique focusing effect of TGGC overcomes many of the previous shortcomings inherent in μGC analyses. PMID:25476685

  14. Atmospheric pressure thermospray ionization using a heated microchip nebulizer.

    PubMed

    Keski-Rahkonen, Pekka; Haapala, Markus; Saarela, Ville; Franssila, Sami; Kotiaho, Tapio; Kostiainen, Risto; Auriola, Seppo

    2009-10-30

    When a standard atmospheric pressure chemical ionization (APCI) or atmospheric pressure photoionization (APPI) ion source is used without applying the corona discharge or photoirradiation, atmospheric pressure thermospray ionization (APTSI) of various compounds can be achieved. Although largely ignored, this phenomenon has recently gained interest as an alternative ionization technique. In this study, this technique is performed for the first time on a miniaturized scale using a microchip nebulizer. Sample ionization with the presented microchip-APTSI (microAPTSI) is achieved by applying only heat and gas flow to a nebulizer chip, without any other methods to promote gas-phase ionization. To evaluate the performance of the described microAPTSI setup, ionization efficiency for a set of test compounds was monitored as the microchip positioning, temperature, nebulizer gas flow rate, sample solution composition, and solvent flow rate were varied. The microAPTSI mass spectra of the test compounds were also compared to those obtained with ESI and APCI. The microAPTSI produces ESI-like spectra with low background noise, favoring the formation of protonated or deprotonated molecules of compounds that are ionizable in solution. Multiple charging of peptides without in-source fragmentation was also observed. Unlike ESI, however, the microAPTSI source can tolerate the presence of mobile phase additives like trifluoroacetic acid (TFA) without significant ion suppression. The microAPTSI source can be used with standard mass spectrometer ion source hardware, being a unique alternative to the present interfacing techniques.

  15. Precolumn reactions with electrophoretic analysis integrated on a microchip

    SciTech Connect

    Jacobson, S.C.; Hergenroeder, R.; Moore, A.W. Jr.; Ramsey, J.M. )

    1994-12-01

    A glass microchip was constructed to perform chemical reactions and capillary electrophoresis sequentially. The channel manifold on the glass substrate was fabricated using standard photolithographic, etching, and deposition techniques. The microchip has a reaction chamber with a 1 nL reaction volume and a separation column with a 15.4 mm separation length. Electrical control of the buffer, analyte, and reagent streams made possible the precise manipulation of the fluids within the channel manifold. The microchip was operated under a continuous reaction mode with gated injections to introduce the reaction product onto the separation column with high reproducibility (<1.8% rsd in peak area). The reaction and separation performances were evaluated by reacting amino acids with o-phthaldialdehyde to generate a fluorescent product which was detected by laser-induced fluorescence. Control of the reaction and separation conditions was sufficient to measure reaction kinetics and variation of detection limits with reaction time. Half-times of reaction of 5.1 and 6.2 s and detection limits of 0.55 and 0.83 fmol were measured for arginine and glycine, respectively. 18 refs., 10 figs.

  16. Microchip-based human serum atherogenic lipoprotein profile analysis.

    PubMed

    Wang, Hua; Zhang, Wei; Wan, Jun; Liu, Weiwei; Yu, Bo; Jin, Qinghui; Guan, Ming

    2014-12-15

    Owing to the mounting evidence of serum lipid changes in atherosclerosis, there has been increasing interest in developing new methods for analyzing atherogenic lipoprotein profiles. The separation of lipoprotein and lipoprotein subclasses has been demonstrated using a microchip capillary electrophoresis (CE) system [Chromatographia 74 (2011) 799-805]. In contrast to this previous study, the current report demonstrates that sdLDL peak efficiencies can be improved dramatically by adding gold nanoparticles (AuNPs) to the sample. Moreover, NBD C6-ceramide was identified as a satisfactory dye for specific labeling and quantitation of individual serum lipoproteins. The accuracy of the method was evaluated by comparison with ultracentrifuge separated small, dense, low-density lipoprotein (sdLDL). A high correlation was observed between these two methods for sdLDL cholesterol. Lipid levels were investigated between atherosclerotic patients and healthy controls. The variation of serum atherogenic lipoprotein profiles for atherosclerotic patients pre- and post-treatment was assessed by microchip CE. This method has potential for the rapid and sensitive detection of different lipoprotein classes as well as their subclasses and, therefore, is suitable for routine clinical applications. Microchip-based atherogenic lipoprotein profile assays will greatly improve the analysis of risk factors in atherosclerosis and will provide useful information for monitoring the effect of therapies on atherosclerotic disease.

  17. Nucleic Acid Isolation and Enrichment on a Microchip.

    PubMed

    Kim, Jinho; Hilton, John P; Yang, Kyung A; Pei, Renjun; Stojanovic, Milan; Lin, Qiao

    2013-06-01

    This paper presents a microchip that isolates and enriches target-binding single-stranded DNA (ssDNA) from a randomized DNA mixture using a combination of solid-phase extraction and electrophoresis. Strands of ssDNA in a randomized mixture are captured via specific binding onto target-functionalized microbeads in a microchamber. The strands are further separated from impurities and enriched on-chip via electrophoresis. The microchip consists of two microchambers that are connected by a channel filled with agarose gel. In the isolation chamber, beads functionalized with human immunoglobulin E (IgE) are retained by a weir structure. An integrated heater elevates the temperature in the chamber to elute desired ssDNA from the beads, and electrophoretic transport of the DNA through the gel to the second chamber is accomplished by applying an electric potential difference between the two chambers. Experimental results show that ssDNA expressing binding affinity to IgE was captured and enriched from a sample of ssDNA with random sequences, demonstrating the potential of the microchip to enhance the sensitivity of ssDNA detection methods in dilute and complex biological samples.

  18. [Development of microchips for the analysis of biomarkers in blood].

    PubMed

    Kataoka, Masatoshi; Abe, Kaori; Hashimoto, Yoshiko; Yamamura, Shohei; Yatsushiro, Shouki

    2012-11-01

    Several types of microchips have been developed for application in clinical diagnosis. A microchip made of cyclic olefin copolymer with straight microchannels (300 microm width and 100 microm depth) was employed for sandwich ELISA for the determination of serum type I C-peptide (PICP), a biomarker of osteoporosis. This assay enabled us to determine PICP with accuracy and high sensitivity, reducing the time for the immunoassay to 1/6, and the consumption of samples and reagents to 1/50 compared with the conventional method. Furthermore, cell microarray chips with 20,944 microchambers (105 microm width and 50 microm depth), made of polystyrene, were employed for malaria diagnosis and the detection of carcinoma cells among the leukocytes. Around 100 erythrocytes or leukocytes were accommodated in each microchamber with the formation of a monolayer. For malaria diagnosis, it offered 10-100 times higher sensitivity in the detection of malaria infected erythrocytes than conventional light microscopy, and easy operation within 15 min. By double staining for epithelial cells on the cell microarray chip, one carcinoma cell could be detected among 1,800,000 leukocytes. These results indicate the potential of microchips for clinic diagnosis.

  19. Portable vapor diffusion coefficient meter

    DOEpatents

    Ho, Clifford K.

    2007-06-12

    An apparatus for measuring the effective vapor diffusion coefficient of a test vapor diffusing through a sample of porous media contained within a test chamber. A chemical sensor measures the time-varying concentration of vapor that has diffused a known distance through the porous media. A data processor contained within the apparatus compares the measured sensor data with analytical predictions of the response curve based on the transient diffusion equation using Fick's Law, iterating on the choice of an effective vapor diffusion coefficient until the difference between the predicted and measured curves is minimized. Optionally, a purge fluid can forced through the porous media, permitting the apparatus to also measure a gas-phase permeability. The apparatus can be made lightweight, self-powered, and portable for use in the field.

  20. Compact portable electric power sources

    SciTech Connect

    Fry, D.N.; Holcomb, D.E.; Munro, J.K.; Oakes, L.C.; Matson, M.J.

    1997-02-01

    This report provides an overview of recent advances in portable electric power source (PEPS) technology and an assessment of emerging PEPS technologies that may meet US Special Operations Command`s (SOCOM) needs in the next 1--2- and 3--5-year time frames. The assessment was performed through a literature search and interviews with experts in various laboratories and companies. Nineteen PEPS technologies were reviewed and characterized as (1) PEPSs that meet SOCOM requirements; (2) PEPSs that could fulfill requirements for special field conditions and locations; (3) potentially high-payoff sources that require additional R and D; and (4) sources unlikely to meet present SOCOM requirements. 6 figs., 10 tabs.

  1. PORTABLE ACOUSTIC MONITORING PACKAGE (PAMP)

    SciTech Connect

    John l. Loth; Gary J. Morris; George M. Palmer; Richard Guiler; Deepak Mehra

    2003-07-01

    The 1st generation acoustic monitoring package was designed to detect and analyze weak acoustic signals inside natural gas transmission lines. Besides a microphone it housed a three-inch diameter aerodynamic acoustic signal amplifier to maximize sensitivity to leak induced {Delta}p type signals. The theory and test results of this aerodynamic signal amplifier was described in the master's degree thesis of our Research Assistant Deepak Mehra who is about to graduate. To house such a large three-inch diameter sensor required the use of a steel 300-psi rated 4 inch weld neck flange, which itself weighed already 29 pounds. The completed 1st generation Acoustic Monitoring Package weighed almost 100 pounds. This was too cumbersome to mount in the field, on an access port at a pipeline shut-off valve. Therefore a 2nd generation and truly Portable Acoustic Monitor was built. It incorporated a fully self-contained {Delta}p type signal sensor, rated for line pressures up to 1000 psi with a base weight of only 6 pounds. This is the Rosemont Inc. Model 3051CD-Range 0, software driven sensor, which is believed to have industries best total performance. Its most sensitive unit was purchased with a {Delta}p range from 0 to 3 inch water. This resulted in the herein described 2nd generation: Portable Acoustic Monitoring Package (PAMP) for pipelines up to 1000 psi. Its 32-pound total weight includes an 18-volt battery. Together with a 3 pound laptop with its 4-channel data acquisition card, completes the equipment needed for field acoustic monitoring of natural gas transmission pipelines.

  2. Reduced-size microchips for identification of horses: response to implantation and readability during a six-month period.

    PubMed

    Wulf, M; Aurich, C; von Lewinski, M; Möstl, E; Aurich, J E

    2013-11-01

    In this study, readability of reduced-size microchips in horses and the response to implantation were analysed. It was hypothesised that small microchips can be implanted stress-free but are less readable than larger microchips. Adult mares (n=40) were implanted with a reduced-size microchip (10.9×1.6 mm) at the left side of the neck (size of conventional microchips 11.4×2.2 mm). Microchips were identified with three different scanners (A, B, C) immediately, and at 6, 12 and 28 weeks after implantation. Twelve out of the 40 mares were submitted to microchip implantation and control treatments and cortisol, heart rate and heart rate variability (HRV) were determined. From the chip-bearing side of the neck, microchips were identified with all scanners in all horses at all times. From the contralateral side, correct readings were always 100 per cent with scanner C and with scanners A and B ranged between 60 and 100 per cent. Heart rate and HRV variable sd of beat-to-beat interval increased slightly (P<0.01) at microchip implantation and control treatment, but cortisol concentration did not increase. In conclusion, reduced-size microchips are highly reliable for identification of horses. Compared with conventional microchips, the reduction in size did not impair readability. Microchip implantation is no pronounced stressor for horses.

  3. Yb:KYW microchip laser with self-frequency Raman conversion

    SciTech Connect

    Grabtchikov, A S; Kuzmin, A N; Lisinetskii, V A; Orlovich, V A; Voitovich, A P; Demidovich, A A; Eichler, H J; Titov, A N

    2003-02-28

    Passively Q-switched and cw operation regimes of a diode-pumped Yb:KYW microchip laser have been investigated. The maximum slope efficiency for cw operation of 23% relative to incident pump power has been achieved. Self-frequency Raman conversion for microchip cavity configuration has been realised. (lasers)

  4. SU-8/Pyrex microchip electrophoresis with integrated electrochemical detection for class-selective electrochemical index determination of phenolic compounds in complex samples.

    PubMed

    Castañeda, Raquel; Vilela, Diana; González, María Cristina; Mendoza, Sandra; Escarpa, Alberto

    2013-07-01

    A SU-8/Pyrex single-channel microchip integrating three 100 μm Pt electrodes (MCE-ED) for class-selective electrochemical index determination (CSEID) of phenolic acids and flavonoids in complex extracts of Tagetes lucida (Tl), Mentha piperita (Mp), Cymbopogon citratus (Cc), Calendula officinalis (Co), and Cynara scolymus (Cs) is proposed. Under strategic conditions controlled by a MES buffer (pH 5.0; 25 mM) and accordingly to the antioxidant acid-base properties, the simultaneous measurement of total acids and flavonoids indexes was achieved in less than 100 s with excellent analytical performance. The reliability of MCE-ED approach was demonstrated toward the high agreement between the total phenolic content obtained using microchip approach with those obtained by the well-established HPLC-DAD; revealing both identical order regarding the total phenolic content in the target samples. In addition, further comparison of MCE-ED with the traditional Folin-Ciocalteu antioxidant capacity assay, showed that MCE-ED approach could become a class-selective antioxidant capacity assay revealing that the sample antioxidant capacity was decreasing as Tl > Mp > Cs > Cc > Co according to their endogenous polyphenol content. These results suggested that the microchip approach is not only a reliable method for fast assessment of class-selective antioxidants constituting a very good alternative to the long analysis times and the using of toxic solvents required in HPLC but a novel truly antioxidant capacity assay. This excellent analytical performance is connected with the key-features of the "ready-to-use" system employed in this work such as portability, full integration of electrochemical detection, easy-operation, and potential MCE-ED disposability.

  5. SU-8/Pyrex microchip electrophoresis with integrated electrochemical detection for class-selective electrochemical index determination of phenolic compounds in complex samples.

    PubMed

    Castañeda, Raquel; Vilela, Diana; González, María Cristina; Mendoza, Sandra; Escarpa, Alberto

    2013-07-01

    A SU-8/Pyrex single-channel microchip integrating three 100 μm Pt electrodes (MCE-ED) for class-selective electrochemical index determination (CSEID) of phenolic acids and flavonoids in complex extracts of Tagetes lucida (Tl), Mentha piperita (Mp), Cymbopogon citratus (Cc), Calendula officinalis (Co), and Cynara scolymus (Cs) is proposed. Under strategic conditions controlled by a MES buffer (pH 5.0; 25 mM) and accordingly to the antioxidant acid-base properties, the simultaneous measurement of total acids and flavonoids indexes was achieved in less than 100 s with excellent analytical performance. The reliability of MCE-ED approach was demonstrated toward the high agreement between the total phenolic content obtained using microchip approach with those obtained by the well-established HPLC-DAD; revealing both identical order regarding the total phenolic content in the target samples. In addition, further comparison of MCE-ED with the traditional Folin-Ciocalteu antioxidant capacity assay, showed that MCE-ED approach could become a class-selective antioxidant capacity assay revealing that the sample antioxidant capacity was decreasing as Tl > Mp > Cs > Cc > Co according to their endogenous polyphenol content. These results suggested that the microchip approach is not only a reliable method for fast assessment of class-selective antioxidants constituting a very good alternative to the long analysis times and the using of toxic solvents required in HPLC but a novel truly antioxidant capacity assay. This excellent analytical performance is connected with the key-features of the "ready-to-use" system employed in this work such as portability, full integration of electrochemical detection, easy-operation, and potential MCE-ED disposability. PMID:23595251

  6. Solar heated portable structure

    SciTech Connect

    Fodor, E.V.; King, F.F.; King, J.M.

    1982-03-23

    A solar heated portable structure comprising a flexible bottom panel, a flexible side assembly and a flexible transmitting panel , all coupled together and supported to form an enclosed chamber. The transmitting panel is capable of transmitting a majority of the radiant energy from the solar radiation spectrum to heat the enclosed chamber like a sauna and has an area at least 0.7 the area of the bottom panel to maximize heating while minimizing material costs. The transmitting panel can be transparent to ultraviolet radiation to allow persons inside the chamber to be tanned.

  7. Portable wastewater flow meter

    DOEpatents

    Hunter, Robert M.

    1999-02-02

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under fill pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  8. Portable wastewater flow meter

    DOEpatents

    Hunter, Robert M.

    1990-01-01

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under full pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  9. Portable pathogen detection system

    SciTech Connect

    Colston, Billy W.; Everett, Matthew; Milanovich, Fred P.; Brown, Steve B.; Vendateswaran, Kodumudi; Simon, Jonathan N.

    2005-06-14

    A portable pathogen detection system that accomplishes on-site multiplex detection of targets in biological samples. The system includes: microbead specific reagents, incubation/mixing chambers, a disposable microbead capture substrate, and an optical measurement and decoding arrangement. The basis of this system is a highly flexible Liquid Array that utilizes optically encoded microbeads as the templates for biological assays. Target biological samples are optically labeled and captured on the microbeads, which are in turn captured on an ordered array or disordered array disposable capture substrate and then optically read.

  10. Portable data collection device

    DOEpatents

    French, Patrick D.

    1996-01-01

    The present invention provides a portable data collection device that has a variety of sensors that are interchangeable with a variety of input ports in the device. The various sensors include a data identification feature that provides information to the device regarding the type of physical data produced by each sensor and therefore the type of sensor itself. The data identification feature enables the device to locate the input port where the sensor is connected and self adjust when a sensor is removed or replaced. The device is able to collect physical data, whether or not a function of a time.

  11. Portable data collection device

    DOEpatents

    French, P.D.

    1996-06-11

    The present invention provides a portable data collection device that has a variety of sensors that are interchangeable with a variety of input ports in the device. The various sensors include a data identification feature that provides information to the device regarding the type of physical data produced by each sensor and therefore the type of sensor itself. The data identification feature enables the device to locate the input port where the sensor is connected and self adjust when a sensor is removed or replaced. The device is able to collect physical data, whether or not a function of a time. 7 figs.

  12. Portable hydrogenerating apparatus

    SciTech Connect

    Borgren, P.M.

    1982-04-13

    Apparatus for generating hydroelectric power comprising a portable collector tube assembly which can be transported to the site of a water source having a waterfall sufficient in magnitude to provide a pressure head for driving a turbine generator. The tube assembly comprises telescopically arranged inner and outer tubes, and means for rotating the tube assembly and extending the inner tube so as to place the upper, extended end thereof in a position within and below the top of the waterfall so as to take advantage of the resulting hydrodynamic and hydrostatic forces.

  13. Portable emittance measurement device

    SciTech Connect

    Liakin, D.; Seleznev, D.; Orlov, A.; Kuibeda, R.; Kropachev, G.; Kulevoy, T.; Yakushin, P.

    2010-02-15

    In Institute for Theoretical and Experimental Physics (ITEP) the portable emittance measurements device is developed. It provides emittance measurements both with ''pepper-pot'' and ''two slits'' methods. Depending on the method of measurements, either slits or pepper-pot mask with scintillator are mounted on the two activators and are installed in two standard Balzer's cross chamber with CF-100 flanges. To match the angle resolution for measured beam, the length of the stainless steel pipe between two crosses changes is adjusted. The description of the device and results of emittance measurements at the ITEP ion source test bench are presented.

  14. Portable classroom leads to partnership.

    PubMed

    Le Ber, Jeanne Marie; Lombardo, Nancy T; Weber, Alice; Bramble, John

    2004-01-01

    Library faculty participation on the School of Medicine Curriculum Steering Committee led to a unique opportunity to partner technology and teaching utilizing the library's portable wireless classroom. The pathology lab course master expressed a desire to revise the curriculum using patient cases and direct access to the Web and library resources. Since the pathology lab lacked computers, the library's portable wireless classroom provided a solution. Originally developed to provide maximum portability and flexibility, the wireless classroom consists of ten laptop computers configured with wireless cards and an access point. While the portable wireless classroom led to a partnership with the School of Medicine, there were additional benefits and positive consequences for the library.

  15. Comparison of Digital Rectal and Microchip Transponder Thermometry in Ferrets (Mustela putorius furo).

    PubMed

    Maxwell, Branden M; Brunell, Marla K; Olsen, Cara H; Bentzel, David E

    2016-01-01

    Body temperature is a common physiologic parameter measured in both clinical and research settings, with rectal thermometry being implied as the 'gold standard.' However, rectal thermometry usually requires physical or chemical restraint, potentially causing falsely elevated readings due to animal stress. A less stressful method may eliminate this confounding variable. The current study compared 2 types of digital rectal thermometers-a calibrated digital thermometer and a common digital thermometer-with an implantable subcutaneous transponder microchip. Microchips were implanted subcutaneously between the shoulder blades of 16 ferrets (8 male, 8 female), and temperatures were measured twice from the microchip reader and once from each of the rectal thermometers. Results demonstrated the microchip temperature readings had very good to good correlation and agreement to those from both of the rectal thermometers. This study indicates that implantable temperature-sensing microchips are a reliable alternative to rectal thermometry for monitoring body temperature in ferrets.

  16. Comparison of Digital Rectal and Microchip Transponder Thermometry in Ferrets (Mustela putorius furo)

    PubMed Central

    Maxwell, Branden M; Brunell, Marla K; Olsen, Cara H; Bentzel, David E

    2016-01-01

    Body temperature is a common physiologic parameter measured in both clinical and research settings, with rectal thermometry being implied as the ‘gold standard.’ However, rectal thermometry usually requires physical or chemical restraint, potentially causing falsely elevated readings due to animal stress. A less stressful method may eliminate this confounding variable. The current study compared 2 types of digital rectal thermometers—a calibrated digital thermometer and a common digital thermometer—with an implantable subcutaneous transponder microchip. Microchips were implanted subcutaneously between the shoulder blades of 16 ferrets (8 male, 8 female), and temperatures were measured twice from the microchip reader and once from each of the rectal thermometers. Results demonstrated the microchip temperature readings had very good to good correlation and agreement to those from both of the rectal thermometers. This study indicates that implantable temperature-sensing microchips are a reliable alternative to rectal thermometry for monitoring body temperature in ferrets. PMID:27177569

  17. Comparison of Digital Rectal and Microchip Transponder Thermometry in Ferrets (Mustela putorius furo).

    PubMed

    Maxwell, Branden M; Brunell, Marla K; Olsen, Cara H; Bentzel, David E

    2016-01-01

    Body temperature is a common physiologic parameter measured in both clinical and research settings, with rectal thermometry being implied as the 'gold standard.' However, rectal thermometry usually requires physical or chemical restraint, potentially causing falsely elevated readings due to animal stress. A less stressful method may eliminate this confounding variable. The current study compared 2 types of digital rectal thermometers-a calibrated digital thermometer and a common digital thermometer-with an implantable subcutaneous transponder microchip. Microchips were implanted subcutaneously between the shoulder blades of 16 ferrets (8 male, 8 female), and temperatures were measured twice from the microchip reader and once from each of the rectal thermometers. Results demonstrated the microchip temperature readings had very good to good correlation and agreement to those from both of the rectal thermometers. This study indicates that implantable temperature-sensing microchips are a reliable alternative to rectal thermometry for monitoring body temperature in ferrets. PMID:27177569

  18. [Theoretical and Experimental Dosimetry in Evaluation of Biological Effects of Electromagnetic Field for Portable Radio Transmitters. Report 2. Homogeneous Human Head Phantom].

    PubMed

    Perov, S Yu; Bogacheva, E V

    2015-01-01

    Results of theoretical (numerical) and experimental electromagnetic field dosimetry for homogeneous human head phantoms are considered. The simulation and measurement results are shown. This paper presents the results of Specific Absorption Rate (SAR) evaluation in the "special anthropomorphic model" of human head, when a source of electromagnetic radio frequency field is placed in front of the face. The minimal difference is shown between measurements and simulation results in Head Simulating Liquid, which makes it possible to conduct further brain tissue simulations. The investigations show that the type of electromagnetic field source and phantom form play an important part for SAR distribution. PMID:26601543

  19. [Theoretical and Experimental Dosimetry in Evaluation of Biological Effects of Electromagnetic Field for Portable Radio Transmitters. Report 2. Homogeneous Human Head Phantom].

    PubMed

    Perov, S Yu; Bogacheva, E V

    2015-01-01

    Results of theoretical (numerical) and experimental electromagnetic field dosimetry for homogeneous human head phantoms are considered. The simulation and measurement results are shown. This paper presents the results of Specific Absorption Rate (SAR) evaluation in the "special anthropomorphic model" of human head, when a source of electromagnetic radio frequency field is placed in front of the face. The minimal difference is shown between measurements and simulation results in Head Simulating Liquid, which makes it possible to conduct further brain tissue simulations. The investigations show that the type of electromagnetic field source and phantom form play an important part for SAR distribution.

  20. The Evaluation of Two Commercially Available, Portable Raman Systems

    PubMed Central

    Mosier-Boss, Pamela A.; Putnam, Michael D.

    2013-01-01

    Raman spectroscopy and surface enhanced Raman spectroscopy (SERS) have many attributes that make them attractive for field detection of environmental contaminants, industrial process control, as well as materials detection/identification in agriculture, pharmaceuticals, law enforcement/first responders, geology, and archeology. However, portable, robust, inexpensive Raman systems are required for these applications. In this communication, the performances of two commercially available, portable Raman systems are evaluated. PMID:24115834

  1. Realistic Planning with Portable Classrooms.

    ERIC Educational Resources Information Center

    Roman, Michael I.

    2002-01-01

    Discusses why it is not wise to address the need for short-term space with the least expensive portable classrooms available. Explains that the problem is not that minimum specification trailers deteriorate rapidly with poor maintenance, but that perceived short-term requirements often turn out to be long-term. Asserts that portable classrooms…

  2. 29 CFR 1917.119 - Portable ladders.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Requirements for Portable Reinforced Plastic Ladders (d) Standards for job-made portable ladders. Job-made... length. (e) Maintenance and inspection. (1) The employer shall maintain portable ladders in...

  3. 29 CFR 1917.119 - Portable ladders.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Requirements for Portable Reinforced Plastic Ladders (d) Standards for job-made portable ladders. Job-made... length. (e) Maintenance and inspection. (1) The employer shall maintain portable ladders in...

  4. Observation of transverse patterns in an isotropic microchip laser

    SciTech Connect

    Chen, Y.F.; Lan, Y.P.

    2003-04-01

    An isotropic microchip laser is used to study the characteristics of high-order wave functions in a two-dimensional (2D) quantum harmonic oscillator based on the identical functional forms. With a doughnut pump profile, the spontaneous transverse modes are found to, generally, be elliptic and hyperbolic transverse modes. Theoretical analyses reveal that the elliptic transverse modes are analogous to the coherent states of a 2D harmonic oscillator; the formation of hyperbolic transverse modes is a spontaneous mode locking between two identical Hermite-Gaussian modes.

  5. View northeast of a microchip based computer control system installed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View northeast of a microchip based computer control system installed in the early 1980's to replace Lamokin Tower, at center of photograph; panels 1 and 2 at right of photograph are part of main supervisory board; panel 1 controlled Allen Lane sub-station #7; responsiblity for this portion of the system was transferred to southeast Pennsylvania transit authority (septa) in 1985; panel 2 at extreme right controls catenary switches in a coach storage yard adjacent to the station - Thirtieth Street Station, Power Director Center, Thirtieth & Market Streets in Amtrak Railroad Station, Philadelphia, Philadelphia County, PA

  6. Magnetic microchip traps and single-atom detection

    NASA Astrophysics Data System (ADS)

    Long, Romain; Steinmetz, Tilo; Hommelhoff, Peter; Hansel, Wolfgang; Hansch, Theodor W.; Reichel, Jakob

    2003-07-01

    Microchip traps provide a promising approach to quantum information processing and communication (QIPC) with neutral atoms: strong and complex potentials can be produced for acting on the qubit atoms, and the potentials can be scaled to higher qubit numbers by virtue of the microfabrication process. We describe experimental results that are relevant to use in QIPC, such as the transport of Bose-Einstein-condensed atomic ensembles along the chip surface with the help of a magnetic conveyor belt. The second part of the paper is devoted to single-atom detection on the chip.

  7. Magnetic microchip traps and single-atom detection.

    PubMed

    Long, Romain; Steinmetz, Tilo; Hommelhoff, Peter; Hänsel, Wolfgang; Hänsch, Theodor W; Reichel, Jakob

    2003-07-15

    Microchip traps provide a promising approach to quantum information processing and communication (QIPC) with neutral atoms: strong and complex potentials can be produced for acting on the qubit atoms, and the potentials can be scaled to higher qubit numbers by virtue of the microfabrication process. We describe experimental results that are relevant to use in QIPC, such as the transport of Bose-Einstein-condensed atomic ensembles along the chip surface with the help of a magnetic conveyor belt. The second part of the paper is devoted to single-atom detection on the chip.

  8. Portable Hyperbaric Chamber

    NASA Technical Reports Server (NTRS)

    Schneider, William C. (Inventor); Locke, James P. (Inventor); DeLaFuente, Horacio (Inventor)

    2001-01-01

    A portable, collapsible hyperbaric chamber was developed. A toroidal inflatable skeleton provides initial structural support for the chamber, allowing the attendant and/or patient to enter the chamber. Oval hatches mate against bulkhead rings, and the hyperbaric chamber is pressurized. The hatches seal against an o-ring, and the internal pressure of the chamber provides the required pressure against the hatch to maintain an airtight seal. In the preferred embodiment, the hyperbaric chamber has an airlock to allow the attendant to enter and exit the patient chamber during treatment. Visual communication is provided through portholes in the patient and/or airlock chamber. Life monitoring and support systems are in communication with the interior of the hyperbaric chamber and/or airlock chamber through conduits and/or sealed feed-through connectors into the hyperbaric chamber.

  9. Portable Cooler/Warmers

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Early in the space program, NASA recognized the need to replace bulky coils, compressers, and motors for refrigeration purposes by looking at existing thermoelectric technology. This effort resulted in the development of miniaturized thermoelectric components and packaging to accommodate tight confines of spacecraft. Koolatron's portable electronic refrigerators incorporate this NASA technology. Each of the cooler/warmers employs one or two miniaturized thermoelectric modules. Although each module is only the size of a book of matches, it delivers the cooling power of a 10-pound block of ice. In some models, the cooler can be converted to a warmer. There are no moving parts. The Koolatrons can be plugged into auto cigarette lighters, recreational vehicles, boats or motel outlets.

  10. Portable Medical System

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Portable Medical Status and Treatment System (PMSTS) is designed for use in remote areas where considerable time may elapse before a patient can be transported to a hospital. First units were delivered to the Department of Transportation last year and tested in two types of medical emergency environments: one in a rural Pennsylvania community and another aboard a U.S. Coast Guard rescue helicopter operating along Florida's Gulf Coast. The system has the capability to transmit vital signs to a distantly located physician, who can perform diagnosis and relay treatment instructions to the attendant at the scene. The battery powered PMSTS includes a vital signs monitor and a defibrillator. Narco has also developed a companion system, called Porta-Fib III designed for use in a hospital environment with modifications accordingly. Both systems are offshoots of an earlier NASA project known as the Physician's Black Bag developed by Telecare, Inc., a company now acquired by NARCO.

  11. Portable intensity interferometry

    NASA Astrophysics Data System (ADS)

    Horch, Elliott P.; Camarata, Matthew A.

    2012-07-01

    A limitation of the current generation of long baseline optical interferometers is the need to make the light interfere prior to detection. This is unlike the radio regime where signals can be recorded fast enough to use electronics to accomplish the same result. This paper describes a modern optical intensity interferometer based on electronics with picosecond timing resolution. The instrument will allow for portable optical interferometry with much larger baselines than currently possible by using existing large telescopes. With modern electronics, the limiting magnitude of the technique at a 4-m aperture size becomes competitive with some amplitude-based interferometers. The instrumentation will permit a wireless mode of operation with GPS clocking technology, extending the work to extremely large baselines. We discuss the basic observing strategy, a planned observational program at the Lowell Observatory 1.8-m and 1.0-m telescopes, and the science that can realistically be done with this instrumentation.

  12. Portable, wheeled cooler apparatus

    SciTech Connect

    Bartholomew, A.E.; Miller, J.L.

    1988-02-16

    A portable, wheeled cooler apparatus adapted to be supported on and easily moved along a support surface is described comprising; (a) a cooler chest assembly including a support container member having an enclosure lid member connected thereto to hold ice and/or other contents therein for insulating purposes; (b) a support wheel assembly connected to the cooler chest assembly operable for supporting on the support surface; and (c) a combination handle and lock assembly connected to an upright wall of the support container member of the cooler chest assembly and operable (1) in one position extended over the enclosure lid member and against another upright wall of the support container member to hold the cooler chest assembly in an enclosed, locked condition; and (2) in a second extended rigid condition to provide a handle assembly for ease of inclining and moving the cooler chest assembly by pulling or pushing on the support wheel assembly.

  13. Physiological and behavioural responses of young horses to hot iron branding and microchip implantation.

    PubMed

    Erber, R; Wulf, M; Becker-Birck, M; Kaps, S; Aurich, J E; Möstl, E; Aurich, C

    2012-02-01

    Branding is the traditional and well-established method used to mark horses, but recently microchip transponders for implantation have become available. In this study, behaviour, physiological stress variables and skin temperature in foals were determined in response to hot-iron branding (n=7) and microchip implantation (n=7). Salivary cortisol concentrations increased in response to branding (1.8 ± 0.2 ng/mL) and microchip implantation (1.4 ± 0.1ng/mL), but cortisol release over time did not differ. In response to both manipulations there was a transient increase in heart rate (P<0.001) and heart rate variability (P<0.01). Branding and microchip implantation induced a comparable aversive behaviour (branding, score 3.86 ± 0.85; microchip, score 4.00 ± 0.82). Both techniques thus caused similar physiological and behavioural changes indicative of stress. Acutely, implantation of a microchip was as stressful as branding in foals. Branding caused a necrotising skin burn lasting at least 7 days. Moreover branding, but not microchip implantation (P<0.001), was accompanied by a generalized increase in skin temperature which was comparable to low degree post-burn hypermetabolism in humans.

  14. DNA analysis using an integrated microchip for multiplex PCR amplification and electrophoresis for reference samples.

    PubMed

    Le Roux, Delphine; Root, Brian E; Reedy, Carmen R; Hickey, Jeffrey A; Scott, Orion N; Bienvenue, Joan M; Landers, James P; Chassagne, Luc; de Mazancourt, Philippe

    2014-08-19

    A system that automatically performs the PCR amplification and microchip electrophoretic (ME) separation for rapid forensic short tandem repeat (STR) forensic profiling in a single disposable plastic chip is demonstrated. The microchip subassays were optimized to deliver results comparable to conventional benchtop methods. The microchip process was accomplished in sub-90 min compared with >2.5 h for the conventional approach. An infrared laser with a noncontact temperature sensing system was optimized for a 45 min PCR compared with the conventional 90 min amplification time. The separation conditions were optimized using LPA-co-dihexylacrylamide block copolymers specifically designed for microchip separations to achieve accurate DNA size calling in an effective length of 7 cm in a plastic microchip. This effective separation length is less than half of other reports for integrated STR analysis and allows a compact, inexpensive microchip design. This separation quality was maintained when integrated with microchip PCR. Thirty samples were analyzed conventionally and then compared with data generated by the microfluidic chip system. The microfluidic system allele calling was 100% concordant with the conventional process. This study also investigated allelic ladder consistency over time. The PCR-ME genetic profiles were analyzed using binning palettes generated from two sets of allelic ladders run three and six months apart. Using these binning palettes, no allele calling errors were detected in the 30 samples demonstrating that a microfluidic platform can be highly consistent over long periods of time.

  15. Self-transport and self-alignment of microchips using microscopic rain

    NASA Astrophysics Data System (ADS)

    Chang, Bo; Shah, Ali; Zhou, Quan; Ras, Robin H. A.; Hjort, Klas

    2015-10-01

    Alignment of microchips with receptors is an important process step in the construction of integrated micro- and nanosystems for emerging technologies, and facilitating alignment by spontaneous self-assembly processes is highly desired. Previously, capillary self-alignment of microchips driven by surface tension effects on patterned surfaces has been reported, where it was essential for microchips to have sufficient overlap with receptor sites. Here we demonstrate for the first time capillary self-transport and self-alignment of microchips, where microchips are initially placed outside the corresponding receptor sites and can be self-transported by capillary force to the receptor sites followed by self-alignment. The surface consists of hydrophilic silicon receptor sites surrounded by superhydrophobic black silicon. Rain-induced microscopic droplets are used to form the meniscus for the self-transport and self-alignment. The boundary conditions for the self-transport have been explored by modeling and confirmed experimentally. The maximum permitted gap between a microchip and a receptor site is determined by the volume of the liquid and by the wetting contrast between receptor site and substrate. Microscopic rain applied on hydrophilic-superhydrophobic patterned surfaces greatly improves the capability, reliability and error-tolerance of the process, avoiding the need for accurate initial placement of microchips, and thereby greatly simplifying the alignment process.

  16. Self-transport and self-alignment of microchips using microscopic rain.

    PubMed

    Chang, Bo; Shah, Ali; Zhou, Quan; Ras, Robin H A; Hjort, Klas

    2015-10-09

    Alignment of microchips with receptors is an important process step in the construction of integrated micro- and nanosystems for emerging technologies, and facilitating alignment by spontaneous self-assembly processes is highly desired. Previously, capillary self-alignment of microchips driven by surface tension effects on patterned surfaces has been reported, where it was essential for microchips to have sufficient overlap with receptor sites. Here we demonstrate for the first time capillary self-transport and self-alignment of microchips, where microchips are initially placed outside the corresponding receptor sites and can be self-transported by capillary force to the receptor sites followed by self-alignment. The surface consists of hydrophilic silicon receptor sites surrounded by superhydrophobic black silicon. Rain-induced microscopic droplets are used to form the meniscus for the self-transport and self-alignment. The boundary conditions for the self-transport have been explored by modeling and confirmed experimentally. The maximum permitted gap between a microchip and a receptor site is determined by the volume of the liquid and by the wetting contrast between receptor site and substrate. Microscopic rain applied on hydrophilic-superhydrophobic patterned surfaces greatly improves the capability, reliability and error-tolerance of the process, avoiding the need for accurate initial placement of microchips, and thereby greatly simplifying the alignment process.

  17. Physiological and behavioural responses of young horses to hot iron branding and microchip implantation.

    PubMed

    Erber, R; Wulf, M; Becker-Birck, M; Kaps, S; Aurich, J E; Möstl, E; Aurich, C

    2012-02-01

    Branding is the traditional and well-established method used to mark horses, but recently microchip transponders for implantation have become available. In this study, behaviour, physiological stress variables and skin temperature in foals were determined in response to hot-iron branding (n=7) and microchip implantation (n=7). Salivary cortisol concentrations increased in response to branding (1.8 ± 0.2 ng/mL) and microchip implantation (1.4 ± 0.1ng/mL), but cortisol release over time did not differ. In response to both manipulations there was a transient increase in heart rate (P<0.001) and heart rate variability (P<0.01). Branding and microchip implantation induced a comparable aversive behaviour (branding, score 3.86 ± 0.85; microchip, score 4.00 ± 0.82). Both techniques thus caused similar physiological and behavioural changes indicative of stress. Acutely, implantation of a microchip was as stressful as branding in foals. Branding caused a necrotising skin burn lasting at least 7 days. Moreover branding, but not microchip implantation (P<0.001), was accompanied by a generalized increase in skin temperature which was comparable to low degree post-burn hypermetabolism in humans. PMID:21917490

  18. Self-transport and self-alignment of microchips using microscopic rain

    PubMed Central

    Chang, Bo; Shah, Ali; Zhou, Quan; Ras, Robin H. A.; Hjort, Klas

    2015-01-01

    Alignment of microchips with receptors is an important process step in the construction of integrated micro- and nanosystems for emerging technologies, and facilitating alignment by spontaneous self-assembly processes is highly desired. Previously, capillary self-alignment of microchips driven by surface tension effects on patterned surfaces has been reported, where it was essential for microchips to have sufficient overlap with receptor sites. Here we demonstrate for the first time capillary self-transport and self-alignment of microchips, where microchips are initially placed outside the corresponding receptor sites and can be self-transported by capillary force to the receptor sites followed by self-alignment. The surface consists of hydrophilic silicon receptor sites surrounded by superhydrophobic black silicon. Rain-induced microscopic droplets are used to form the meniscus for the self-transport and self-alignment. The boundary conditions for the self-transport have been explored by modeling and confirmed experimentally. The maximum permitted gap between a microchip and a receptor site is determined by the volume of the liquid and by the wetting contrast between receptor site and substrate. Microscopic rain applied on hydrophilic-superhydrophobic patterned surfaces greatly improves the capability, reliability and error-tolerance of the process, avoiding the need for accurate initial placement of microchips, and thereby greatly simplifying the alignment process. PMID:26450019

  19. Hand portable thin-layer chromatography system

    DOEpatents

    Haas, Jeffrey S.; Kelly, Fredrick R.; Bushman, John F.; Wiefel, Michael H.; Jensen, Wayne A.

    2000-01-01

    A hand portable, field-deployable thin-layer chromatography (TLC) unit and a hand portable, battery-operated unit for development, illumination, and data acquisition of the TLC plates contain many miniaturized features that permit a large number of samples to be processed efficiently. The TLC unit includes a solvent tank, a holder for TLC plates, and a variety of tool chambers for storing TLC plates, solvent, and pipettes. After processing in the TLC unit, a TLC plate is positioned in a collapsible illumination box, where the box and a CCD camera are optically aligned for optimal pixel resolution of the CCD images of the TLC plate. The TLC system includes an improved development chamber for chemical development of TLC plates that prevents solvent overflow.

  20. Intelligent microchip networks: an agent-on-chip synthesis framework for the design of smart and robust sensor networks

    NASA Astrophysics Data System (ADS)

    Bosse, Stefan

    2013-05-01

    Sensorial materials consisting of high-density, miniaturized, and embedded sensor networks require new robust and reliable data processing and communication approaches. Structural health monitoring is one major field of application for sensorial materials. Each sensor node provides some kind of sensor, electronics, data processing, and communication with a strong focus on microchip-level implementation to meet the goals of miniaturization and low-power energy environments, a prerequisite for autonomous behaviour and operation. Reliability requires robustness of the entire system in the presence of node, link, data processing, and communication failures. Interaction between nodes is required to manage and distribute information. One common interaction model is the mobile agent. An agent approach provides stronger autonomy than a traditional object or remote-procedure-call based approach. Agents can decide for themselves, which actions are performed, and they are capable of flexible behaviour, reacting on the environment and other agents, providing some degree of robustness. Traditionally multi-agent systems are abstract programming models which are implemented in software and executed on program controlled computer architectures. This approach does not well scale to micro-chip level and requires full equipped computers and communication structures, and the hardware architecture does not consider and reflect the requirements for agent processing and interaction. We propose and demonstrate a novel design paradigm for reliable distributed data processing systems and a synthesis methodology and framework for multi-agent systems implementable entirely on microchip-level with resource and power constrained digital logic supporting Agent-On-Chip architectures (AoC). The agent behaviour and mobility is fully integrated on the micro-chip using pipelined communicating processes implemented with finite-state machines and register-transfer logic. The agent behaviour

  1. Resorbable polymer microchips releasing BCNU inhibit tumor growth in the rat 9L flank model.

    PubMed

    Kim, Grace Y; Tyler, Betty M; Tupper, Malinda M; Karp, Jeffrey M; Langer, Robert S; Brem, Henry; Cima, Michael J

    2007-11-01

    Sustained local delivery of single agents and controlled delivery of multiple chemotherapeutic agents are sought for the treatment of brain cancer. A resorbable, multi-reservoir polymer microchip drug delivery system has been tested against a tumor model. The microchip reservoirs were loaded with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). BCNU was more stable at 37 degrees C within the microchip compared to a uniformly impregnated polymeric wafer (70% intact drug vs. 38%, at 48 h). The half-life of the intact free drug in the microchip was 11 days, which is a marked enhancement compared to its half-life in normal saline and 10% ethanol (7 and 10 min, respectively) [P. Tepe, S.J. Hassenbusch, R. Benoit, J.H. Anderson, BCNU stability as a function of ethanol concentration and temperature, J. Neurooncol. 10 (1991) 121-127; P. Kari, W.R. McConnell, J.M. Finkel, D.L. Hill, Distribution of Bratton-Marshall-positive material in mice following intravenous injections of nitrosoureas, Cancer Chemother. Pharmacol. 4 (1980) 243-248]. A syngeneic Fischer 344 9L gliosarcoma rat model was used to study the tumoricidal efficacy of BCNU delivery from the microchip or homogeneous polymer wafer. A dose-dependent decrease in tumor size was found for 0.17, 0.67, and 1.24 mg BCNU-microchips. Tumors treated with 1.24 mg BCNU-microchips showed significant tumor reduction (p=0.001) compared to empty control microchips at two weeks. The treatment showed similar efficacy to a polymer wafer with the same dosage. The microchip reservoir array may enable delivery of multiple drugs with independent release kinetics and formulations.

  2. Numerical simulation and optimization of passively q-switched erbium microchip lasers

    NASA Astrophysics Data System (ADS)

    Belghachem, Nabil; Mlynczak, Jarslow

    2015-08-01

    In this article we present a procedure of optimization of passively q-switched erbium microchip lasers. The procedure is based on the rate equation model, validated by comparing the numerical results to the experimental results of pulse generation in different types of erbium/ytterbium glass microchips q-switched by Co2+ : MgAl2O4 saturable absorber. Some Degnan’s optimization limitations in case of microchip lasers were also shown and the reabsorbtion cross section of erbium glass was also estimated.

  3. [A novel and facile microchip based on nitrocellulose membrane toward efficient capture of circulating tumor cells].

    PubMed

    Zhang, Peng; Sun, Changlong; Zhang, Ren; Gao, Mingxia; Zhang, Xiangmin

    2013-06-01

    A novel and facile circulating tumor cell (CTC) microchip has been developed for the isolation and detection of cancer cells. The CTC microchip was prepared based on the nitrocellulose membrane substrate, which shows high affinity to proteins and hence can adsorb antibodies naturally. We employed non-small-cells of lung cancer NCI-H1650 as target cells and testified the high capture efficacy of the CTC microchip. Furthermore, we spiked 500 cancer cells to 1 mL healthy donor's whole blood in order to simulate the detection of CTC in patient and detected 182 cancer cells ultimately, indicating the huge application potential in the future.

  4. A micro surface tension pump (MISPU) in a glass microchip.

    PubMed

    Peng, Xing Yue Larry

    2011-01-01

    A non-membrane micro surface tension pump (MISPU) was fabricated on a glass microchip by one-step glass etching. It needs no material other than glass and is driven by digital gas pressure. The MISPU can be seen working like a piston pump inside the glass microchip under a microscope. The design of the valves (MISVA) and pistons (MISTON) was based on the surface tension theory of the micro surface tension alveolus (MISTA). The digital gas pressure controls the moving gas-liquid interface to open or close the input and output MISVAs to refill or drive the MISTON for pumping a liquid. Without any moving parts, a MISPU is a kind of long-lasting micro pump for micro chips that does not lose its water pumping efficiency over a 20-day period. The volumetric pump output varied from 0 to 10 nl s(-1) when the pump cycle time decreased from 5 min to 15 s. The pump head pressure was 1 kPa.

  5. Quantitative analysis of plasma interleiukin-6 by immunoassay on microchip

    NASA Astrophysics Data System (ADS)

    Abe, K.; Hashimoto, Y.; Yatsushiro, S.; Yamamura, S.; Tanaka, M.; Ooie, T.; Baba, Y.; Kataoka, M.

    2012-03-01

    Sandwich enzyme-linked immunoassay (ELISA) is one of the most frequently employed assays for clinical diagnosis, since this enables the investigator to identify specific protein biomarkers. However, the conventional assay using a 96-well microtitration plate is time- and sample-consuming, and therefore is not suitable for rapid diagnosis. To overcome these drawbacks, we performed a sandwich ELISA on a microchip. We employed the piezoelectric inkjet printing for deposition and fixation of 1st antibody on the microchannnel surface (300 μm width and 100 μm depth). Model analyte was interleukin-6 (IL-6) which was one of the inflammatory cytokine. After blocking the microchannel, antigen, biotin-labeled 2nd antibody, and avidin-labeled peroxidase were infused into the microchannel and incubated for 20 min, 10 min, and 5 min, respectively. This assay could detect 2 pg/ml and quantitatively measure the range of 0-32 pg/ml. Liner regression analysis of plasma IL-6 concentration obtained by microchip and conventional methods exhibited a significant relationship (R2 = 0.9964). This assay reduced the time for the antigen-antibody reaction to 1/6, and the consumption of samples and reagents to 1/50 compared with the conventional method. This assay enables us to determine plasma IL-6 with accuracy, high sensitivity, time saving ability, and low consumption of sample and reagents, and thus will be applicable to clinic diagnosis.

  6. Analytical detection of biological thiols in a microchip capillary channel.

    PubMed

    Chand, Rohit; Jha, Sandeep Kumar; Islam, Kamrul; Han, Dawoon; Shin, Ik-Soo; Kim, Yong-Sang

    2013-02-15

    Sulfur-containing amino acids, such as cysteine and homocysteine play crucial roles in biological systems for the diagnosis of medical states. In this regard, this paper deals with separation, aliquot and detection of amino thiols on a microchip capillary electrophoresis with electrochemical detection in an inverted double Y-shaped microchannel. Unlike the conventional capillary electrophoresis, the modified microchannel design helps in storing the separated thiols in different reservoirs for further analysis, if required; and also eliminates the need of electrodes regeneration. The device was fabricated using conventional photolithographic technique which consisted of gold microelectrodes on a soda lime glass wafer and microchannels in PDMS mold. Multiple detections were performed using in-house fabricated dual potentiostat. Based on amperometric detection, cysteine and homocysteine were analyzed in 105 s and 120 s, respectively after diverting in branched channels. Repeated experiments proved the good reproducibility of the device. The device produced a linear response for both cysteine and homocysteine in electrochemical analysis. To prove the practicality of device, we also analyzed cysteine and homocysteine in real blood samples without any pre-treatment. Upon calculation, the device showed a very low limit of detection of 0.05 μM. The modified microchip design shall find a broad range of analytical applications involving assays of thiols and other biological compounds.

  7. Microchip-Associated Sarcoma in a Shrew (Suncus murinus)

    PubMed Central

    Schutt, Leah K; Turner, Patricia V

    2010-01-01

    A 16-mo-old female house musk shrew (Suncus murinus) with a 1-wk history of a rapidly growing subcutaneous mass in the interscapsular region was euthanized and submitted for necropsy. Macroscopic examination identified an irregular, well-demarcated, solid, tan-white subcutaneous mass. A small cavity containing a microchip device was present at the center of the mass. In addition, massive splenomegaly was evident grossly. Histologically, the subcutaneous mass comprised spindle cells arranged in a storiform pattern of interweaving bundles, consistent with a high-grade soft tissue sarcoma with multifocal necrosis. Immunohistochemical investigation suggested that the neoplastic cells were positive for neuron-specific enolase and (rarely) α-smooth muscle actin and negative for cytokeratin, desmin, S100, and vimentin. In light of the mesenchymal histopathologic phenotype and the lack of specific immunoreactivity pattern, the mass was considered to be most consistent with a poorly differentiated sarcoma. To our knowledge, this is the first report of a microchip-associated soft tissue sarcoma in a shrew. PMID:20858367

  8. Energy Conversion from Salinity Gradient Using Microchip with Nafion Membrane

    NASA Astrophysics Data System (ADS)

    Chang, Che-Rong; Yeh, Ching-Hua; Yeh, Hung-Chun; Yang, Ruey-Jen

    2016-06-01

    When a concentrated salt solution and a diluted salt solution are separated by an ion-selective membrane, cations and anions would diffuse at different rates depending on the ion selectivity of the membrane. The difference of positive and negative charges at both ends of the membrane would produce a potential, called the diffusion potential. Thus, electrical energy can be converted from the diffusion potential through reverse electrodialysis. This study demonstrated the fabrication of an energy conversion microchip using the standard micro-electromechanical technique, and utilizing Nafion junction as connecting membrane, which was fabricated by a surface patterned process. Through different salinity gradient of potassium chloride solutions, we experimentally investigated the diffusion potential and power generation from the microchip, and the highest value measured was 135 mV and 339 pW, respectively. Furthermore, when the electrolyte was in pH value of 3.8, 5.6, 10.3, the system exhibited best performance at pH value of 10.3; whereas, pH value of 3.8 yielded the worst.

  9. A Trusted Portable Computing Device

    NASA Astrophysics Data System (ADS)

    Ming-wei, Fang; Jun-jun, Wu; Peng-fei, Yu; Xin-fang, Zhang

    A trusted portable computing device and its security mechanism were presented to solve the security issues, such as the attack of virus and Trojan horse, the lost and stolen of storage device, in mobile office. It used smart card to build a trusted portable security base, virtualization to create a secure virtual execution environment, two-factor authentication mechanism to identify legitimate users, and dynamic encryption to protect data privacy. The security environment described in this paper is characteristic of portability, security and reliability. It can meet the security requirement of mobile office.

  10. A micro-chip initiator with controlled combustion reactivity realized by integrating Al/CuO nanothermite composites on a microhotplate platform

    NASA Astrophysics Data System (ADS)

    Ahn, Ji Young; Kim, Sang Beom; Kim, Ji Hoon; Jang, Nam Su; Kim, Dae Hyun; Lee, Hyung Woo; Kim, Jong Man; Kim, Soo Hyung

    2016-01-01

    The interfacial contact area between the fuel and oxidizer components plays an important role in determining the combustion reactivity of nanothermite composites. In addition, the development of compact and reliable ignition methods can extend the applicability of nanothermite composites to various thermal engineering fields. In this study we report the development of a micro-chip initiator with controlled combustion reactivity using concepts usually applied to microelectromechanical systems (MEMS) and simple nanofabrication processes. The nanothermite composites fabricated in this study consisted of aluminum nanoparticles (Al NPs) as the fuel and copper oxide nanoparticles (CuO NPs) as the oxidizer accumulated on a silicon oxide substrate with a serpentine-shaped gold (Au) electrode. The micro-chip initiator rapidly ignited and exploded when minimal current was supplied. The effects of stacking structures of Al and CuO-based multilayers on the combustion properties were systematically investigated in terms of the pressurization rate, peak explosion time, and heat flow. Pressurization rates of 0.004-0.025 MPa μs-1 and heat flows of 2.0-3.8 kJ g-1 with a commonly fast response time of less than 20 ms could be achieved by simply changing the interfacial structures of the Al and CuO multilayers. The controllability of combustion reactivity of micro-chip initiator can be made for general nanothermite composites composed of Al and various metal oxides (e.g. Fe2O3, CuO, KMnO4, etc). The micro-chip initiator fabricated in this study was reliable, compact, and proved to be a versatile platform, exhibiting controlled combustion reactivity and fast response time, which could be used for various civilian and military thermal engineering applications, such as in initiators and propulsion, welding, and ordinance systems.

  11. Fabrication and functional demonstration of a smart electrode with a built-in CMOS microchip for neural stimulation of a retinal prosthesis.

    PubMed

    Noda, Toshihiko; Fujisawa, Takumi; Kawasaki, Ryohei; Tashiro, Hiroyuki; Takehara, Hiroaki; Sasagawa, Kiyotaka; Tokuda, Takashi; Ohta, Jun

    2015-01-01

    In this study, we propose an advanced architecture of a smart electrode for neural stimulation of a retinal prosthesis. A feature of the proposed architecture is embedding CMOS microchips into the core of the stimulus electrodes. Microchip integration without dead space on the array is possible. Additionally, higher durability can be expected because the microchips are protected by the stimulus electrodes like a metal casing. Dedicated circular-shaped CMOS microchips were designed and fabricated. The microchip measured 400 μm in diameter. Stimulus electrodes that had a microcavity for embedding the microchip were also fabricated. In the assembly process, the CMOS microchip was mounted on a flexible substrate, and then the stimulus electrode was mounted to cover the microchip. The microchip was completely built into the inside of the electrode. By performing an ex-vivo experiment using the extracted eyeball of a pig, stimulus function of the electrode was demonstrated successfully. PMID:26737011

  12. A review of the development of portable laser induced breakdown spectroscopy and its applications

    NASA Astrophysics Data System (ADS)

    Rakovský, J.; Čermák, P.; Musset, O.; Veis, P.

    2014-11-01

    In this review, we present person-transportable laser induced breakdown spectroscopy (LIBS) devices that have previously been developed and reported in the literature as well as their applications. They are compared with X-ray fluorescent (XRF) devices, which represent their strongest competition. Although LIBS devices have advantages over XRF devices, such as sensitivity to the light elements, high spatial resolution and the possibility to distinguish between different layers of the sample, there are also disadvantages and both are discussed here. Furthermore, the essential portable LIBS instrumentation (laser, spectrograph and detector) is presented, and published results related to new laser sources (diode-pumped solid-state, microchip and fiber lasers) used in LIBS are overviewed. Compared to conventional compact flashlamp pumped solid-state lasers, the new laser sources provide higher repetition rates, higher efficiency (less power consumption) and higher beam quality, resulting in higher fluences, even for lower energies, and could potentially increase the figure of merit of portable LIBS instruments. Compact spectrometers used in portable LIBS devices and their parts (spectrograph, detector) are also discussed.

  13. Freely Oriented, Portable Superconducting Magnet

    NASA Astrophysics Data System (ADS)

    Schmierer, E. N.; Charles, B.; Efferson, R.; Hill, D.; Jankowski, T.; Laughon, G.; Prenger, C.

    2008-03-01

    A high-field low-temperature superconducting solenoidal magnet was developed that is portable and can be operated in any orientation relative to gravity. The design consists of several features that make this feasible; 1) bulk liquid cryogen storage occurs in a separate Dewar rather than as part of the magnet assembly, which allows single-person transport due to each component of the system having low relative weight, 2) vapor generated pressurization that circulates cryogenic fluid to and from the magnet with flexible transfer lines allowing operation in any orientation, and 3) composite, low-conducting structural members are used to suspend the magnet and shield layers within the vacuum vessel that provide a robust low heat loss design. Cooling is provided to the magnet through fluid channels that are in thermal contact with the magnet. The overall design of this magnet system, some of the analyses performed that address unique behavior of this system (pressure rise during a magnet quench and transient cooldown), and test results are presented.

  14. Portable rotating discharge plasma device

    NASA Astrophysics Data System (ADS)

    Dwyer, B. L.; Brooks, N. H.; Lee, R. L.

    2011-10-01

    We constructed two devices for the purpose of educational demonstration: a rotating tube containing media of two densities to demonstrate axial confinement and a similar device that uses pressure variation to convert a long plasma glow discharge into a long straight arc. In the first device, the buoyant force is countered by the centripetal force, which confines less dense materials to the center of the column. Similarly, a plasma arc heats the gas through which it passes, creating a hot gaseous bubble that is less dense than the surrounding medium. Rotating its containment envelope stabilizes this gas bubble in an analogous manner to an air bubble in a rotating tube of water. In addition to stabilization, the rotating discharge also exhibits a decrease in buoyancy-driven convection currents. This limits the power loss to the walls, which decreases the field strength requirement for maintaining the arc. These devices demonstrate principles of electrodynamics, plasma physics, and fluid mechanics. They are portable and safe for classroom use. Work supported by US DOE under DE-FC02-04ER54698 and the National Undergraduate Fellowship in Fusion Science and Engineering.

  15. A Portable Infrasonic Detection System

    NASA Technical Reports Server (NTRS)

    Shams, Qamar A.; Burkett, Cecil G.; Zuckerwar, Allan J.; Lawrenson, Christopher C.; Masterman, Michael

    2008-01-01

    During last couple of years, NASA Langley has designed and developed a portable infrasonic detection system which can be used to make useful infrasound measurements at a location where it was not possible previously. The system comprises an electret condenser microphone, having a 3-inch membrane diameter, and a small, compact windscreen. Electret-based technology offers the lowest possible background noise, because Johnson noise generated in the supporting electronics (preamplifier) is minimized. The microphone features a high membrane compliance with a large backchamber volume, a prepolarized backplane and a high impedance preamplifier located inside the backchamber. The windscreen, based on the high transmission coefficient of infrasound through matter, is made of a material having a low acoustic impedance and sufficiently thick wall to insure structural stability. Close-cell polyurethane foam has been found to serve the purpose well. In the proposed test, test parameters will be sensitivity, background noise, signal fidelity (harmonic distortion), and temporal stability. The design and results of the compact system, based upon laboratory and field experiments, will be presented.

  16. Portable Sonic Boom Simulation

    NASA Astrophysics Data System (ADS)

    Salamone, Joe

    2006-05-01

    A method is presented to simulate sonic booms using high fidelity and custom-built audio equipment that output to an acoustically treated listening environment, all of which is contained in a portable vehicle. The audio system has inherent low and high frequency performance limitations and also introduces distortion due to the frequency response of the system. The limitations of the system are compensated for by band-pass filtering a full-fidelity sonic boom signature and applying a system equalization filter. The purpose of the band-pass filter is to remove frequency content above and below the capabilities of the system yet retain the audible and felt characteristics of the full-fidelity waveform. The equalization filter, computed from time-domain Wiener filtering, compensates for the frequency-dependent system response of the audio system at several listening positions. The system performance is evaluated by comparing the PLdB, SEL(A) and SEL(C) of the measured system output to the full-fidelity waveform. Results show good agreement between the loudness levels of the full-fidelity waveform and the corresponding measured system output.

  17. Portable classroom leads to partnership.

    PubMed

    Le Ber, Jeanne Marie; Lombardo, Nancy T; Weber, Alice; Bramble, John

    2004-01-01

    Library faculty participation on the School of Medicine Curriculum Steering Committee led to a unique opportunity to partner technology and teaching utilizing the library's portable wireless classroom. The pathology lab course master expressed a desire to revise the curriculum using patient cases and direct access to the Web and library resources. Since the pathology lab lacked computers, the library's portable wireless classroom provided a solution. Originally developed to provide maximum portability and flexibility, the wireless classroom consists of ten laptop computers configured with wireless cards and an access point. While the portable wireless classroom led to a partnership with the School of Medicine, there were additional benefits and positive consequences for the library. PMID:15148018

  18. A Compact, Transportable, Microchip-Based System for High Repetition Rate Production of Bose-Einstein Condensates

    NASA Astrophysics Data System (ADS)

    Farkas, Daniel; Hudek, Kai; Salim, Evan; Segal, Stephen; Anderson, Dana

    2010-03-01

    We present a compact, transportable system that produces Bose-Einstein condensates (BECs) near the surface of an integrated atom microchip. Occupying a volume of 0.4 m^3 and consuming an average power of 525 W, the system contains all of the components needed to produce and image BECs, including an ultra-high vacuum system, lasers, data acquisition hardware, electronics, and imaging equipment. RF evaporative cooling forms nearly-pure condensates containing 1.9x10^4 ^87Rb atoms in the |F=2,mF=+2> ground hyperfine state. With trap frequencies of several kHz, evaporative cooling times as short as 1.5 s have been used to create BECs, resulting in production repetition rates as high as 0.3 Hz. The system can be easily reconfigured for use with atom chips having wire patterns designed for different applications. As such, it can serve as a standardized platform for a variety of portable experiments that utilize ultracold matter.

  19. Optical nanocluster microchips for human diagnostics

    NASA Astrophysics Data System (ADS)

    Bauer, Georg D.; Volnov, Sabine; Sontag, Gerhard; Leitner, Alfred; Aussenegg, Franz R.; Pittner, Fritz; Schalkhammer, Thomas G. M.

    1999-06-01

    Metal clusters excited by light exhibit high local field enhancement and nanoscale resonant behavior. Absorptive properties of these metal clusters bound to a surface are the basis of various new and highly promising setups to transduce biorecognitive interactions into an optical signal. Multilayered highly resonant systems had been proposed and recently demonstrated employing a metal mirror, a nanometric polymer distance layer, a biomolecule interaction layer and biorecognitively bound metal nano clusters. The optochips clearly exhibit strong reflection minima induced by the resonant behavior of the metal cluster layer. At least one narrow reflection minimum can be shifted to the red or infra red spectral range and therefore far away from spherical gold colloids (less than 520 nm) and human plasma absorption. The setup enabled us to replace conventional binding assays (like ELISA) overcoming the various technological limits as there are multiple incubation steps, harmful reagents and spatial resolution. A modified setup (the metal island coated swelling polymer over mirror system) employing an optical thin-layer system consisting of a metal mirror, an active analyte-induced swelling polymer, and a metal cluster (island) film as the topmost layer was used to transduce human plasma ion concentrations.

  20. Characteristics of High-Resolution Hemoglobin Measurement Microchip Integrated with Signal Processing Circuit

    NASA Astrophysics Data System (ADS)

    Noda, Toshihiko; Takao, Hidekuni; Ashiki, Mitsuaki; Ebi, Hiroyuki; Sawada, Kazuaki; Ishida, Makoto

    2004-04-01

    In this study, a microchip for measurement of hemoglobin in human blood has been proposed, fabricated and evaluated. The measurement principle of hemoglobin is based on the “cyanmethemoglobin method” that calculates the cyanmethemoglobin concentration by absorption photometry. A glass/silicon/silicon structure was used for the microchip. The middle silicon layer includes flow channels, and 45° mirrors formed at each end of the flow channels. Photodiodes and metal oxide semiconductor (MOS) integrated circuits were fabricated on the bottom silicon layer. The performance of the microchip for hemoglobin measurement was evaluated using a solution of red food color instead of a real blood sample. The fabricated microchip exhibited a similar performance to a nonminiaturized absorption cell which has the same optical path length. Signal processing output varied with solution concentration from 5.32 V to 5.55 V with very high stability due to differential signal processing.

  1. Fibrosarcoma adjacent to the site of microchip implantation in a cat.

    PubMed

    Daly, Meighan K; Saba, Corey F; Crochik, Sonia S; Howerth, Elizabeth W; Kosarek, Carrie E; Cornell, Karen K; Roberts, Royce E; Northrup, Nicole C

    2008-04-01

    A 14-year-old spayed female domestic shorthair cat presented with an interscapular mass. A computed tomography scan, biopsy, and histological examination revealed a fibrosarcoma adjacent to a pet identification microchip. Because the cat was previously vaccinated at this site, it is not possible to establish definitive causation of the fibrosarcoma, but this is the first report of a tumor in the vicinity of a microchip in a cat. Microchip-associated tumors have been reported in rodents and dogs. Veterinarians should be aware that because inflammation may predispose felines to tumor formation, separation and observation of vaccination and implantation sites are indicated. Adherence to American Association of Feline Practitioners (AAFP) vaccination guidelines and monitoring of microchip implantation sites are recommended.

  2. Effect of mixing on reaction-diffusion kinetics for protein hydrogel-based microchips.

    PubMed

    Zubtsov, D A; Ivanov, S M; Rubina, A Yu; Dementieva, E I; Chechetkin, V R; Zasedatelev, A S

    2006-03-01

    Protein hydrogel-based microchips are being developed for high-throughput evaluation of the concentrations and activities of various proteins. To shorten the time of analysis, the reaction-diffusion kinetics on gel microchips should be accelerated. Here we present the results of the experimental and theoretical analysis of the reaction-diffusion kinetics enforced by mixing with peristaltic pump. The experiments were carried out on gel-based protein microchips with immobilized antibodies under the conditions utilized for on-chip immunoassay. The dependence of fluorescence signals at saturation and corresponding saturation times on the concentrations of immobilized antibodies and antigen in solution proved to be in good agreement with theoretical predictions. It is shown that the enhancement of transport with peristaltic pump results in more than five-fold acceleration of binding kinetics. Our results suggest useful criteria for the optimal conditions for assays on gel microchips to balance high sensitivity and rapid fluorescence saturation kinetics.

  3. Kinetic effects on signal normalization in oligonucleotide microchips with labeled immobilized probes.

    PubMed

    Pan'kov, S V; Chechetkin, V R; Somova, O G; Antonova, O V; Moiseeva, O V; Prokopenko, D V; Yurasov, R A; Gryadunov, D A; Chudinov, A V

    2009-10-01

    Among various factors affecting operation of oligonucleotide microchips, the variations in concentration and in homogeneous distribution of immobilized probes over the cells are one of the most important. The labeling of immobilized probes ensures the complete current monitoring on the probe distribution and is reliable and convenient. Using hydrogel-based oligonucleotide microchips, the applicability of Cy3-labeled immobilized probes for quality control and signal normalization after hybridization with Cy5-labeled target DNA was investigated. This study showed that proper signal normalization should be different in thermodynamic conditions and in transient regime with hybridization far from saturation. This kinetic effect holds for both hydrogel-based and surface oligonucleotide microchips. Besides proving basic features, the technique was assessed on a sampling batch of 50 microchips developed for identifying mutations responsible for rifampicin and isoniazid resistance of Mycobacterium tuberculosis.

  4. Rapid amplification of genetically modified organisms using a circular ferrofluid-driven PCR microchip.

    PubMed

    Sun, Yi; Kwok, Yien-Chian; Foo-Peng Lee, Peter; Nguyen, Nam-Trung

    2009-07-01

    The use of genetically modified organisms (GMOs) as food and in food products is becoming more and more widespread. Polymerase chain reaction (PCR) technology is extensively used for the detection of GMOs in food products in order to verify compliance with labeling requirements. In this paper, we present a novel close-loop ferrofluid-driven PCR microchip for rapid amplification of GMOs. The microchip was fabricated in polymethyl methacrylate by CO2 laser ablation and was integrated with three temperature zones. PCR solution was contained in a circular closed microchannel and was driven by magnetic force generated by an external magnet through a small oil-based ferrofluid plug. Successful amplification of genetically modified soya and maize were achieved in less than 13 min. This PCR microchip combines advantages of cycling flexibility and quick temperature transitions associated with two existing microchip PCR techniques, and it provides a cost saving and less time-consuming way to conduct preliminary screening of GMOs.

  5. [On-microchip PCR for detection of influenza A viruses subtypes, circulating in the human population].

    PubMed

    Kostina, E V; Ryabinin, V A; Ternovoi, V A; Sinyakov, A N

    2015-01-01

    A oligonucleotide microchip was developed for revealing Influenza A viruses subtypes, circulating in human population: pandemic H1N1 swine influenza viruses, seasonal H1N1, H2N2, H3N2, H5N1, H9N2, H7N9. Typing of influenza virus was performed by on-microchip PCR. We used immobilized primers-probes selected for the neuraminidase gene that allows determining both subtype of neuraminidase and subtype of hemagglutinin. PMID:26050481

  6. [On-microchip PCR for detection of influenza A viruses subtypes, circulating in the human population].

    PubMed

    Kostina, E V; Ryabinin, V A; Ternovoi, V A; Sinyakov, A N

    2015-01-01

    A oligonucleotide microchip was developed for revealing Influenza A viruses subtypes, circulating in human population: pandemic H1N1 swine influenza viruses, seasonal H1N1, H2N2, H3N2, H5N1, H9N2, H7N9. Typing of influenza virus was performed by on-microchip PCR. We used immobilized primers-probes selected for the neuraminidase gene that allows determining both subtype of neuraminidase and subtype of hemagglutinin.

  7. Microchip implant system used for animal identification in laboratory rabbits, guineapigs, woodchucks and in amphibians.

    PubMed

    Mrozek, M; Fischer, R; Trendelenburg, M; Zillmann, U

    1995-07-01

    Traditional methods for animal identification have a number of drawbacks. We evaluated a new system for individual identification using microchip implants in rabbits, guineapigs, woodchucks (Marmota monax) and amphibians (Xenopus laevis, Pleurodeles waltlii). Implantation procedure and long-term observations are described. Microchip implants proved to be a practicable and reliable system for animal identification without obvious adverse effects. The applicability of electronic animal identification in comparison with common methods and with regard to animal welfare and legal aspects is discussed.

  8. Portable source identification device

    NASA Astrophysics Data System (ADS)

    Andersen, Eric S.; Samuel, Todd J.; Gervais, Kevin L.

    2005-05-01

    U.S. Customs and Border Protection (CBP) is the primary enforcement agency protecting the nation"s ports of entry. CBP is enhancing its capability to interdict the illicit import of nuclear and radiological materials and devices that may be used by terrorists. Pacific Northwest National Laboratory (PNNL) is providing scientific and technical support to CBP in their goal to enable rapid deployment of nuclear and radiation detection systems at U. S. ports of entry to monitor 100% of the incoming international traffic and cargo while not adversely impacting the operations or throughput of the ports. As the deployment of radiation detection systems proceeds, there is a need to adapt the baseline radiation portal monitor (RPM) system technology to operations at these diverse ports of entry. When screening produces an alarm in the primary inspection RPM, the alarming vehicle is removed from the flow of commerce and the alarm is typically confirmed in a secondary inspection RPM. The portable source identification device (PSID) is a radiation sensor panel (RSP), based on thallium-doped sodium iodide (NaI(Tl)) scintillation detector and gamma spectroscopic analysis hardware and software, mounted on a scissor lift on a small truck. The lift supports a box containing a commercial off-the-shelf (COTS) sodium iodide detector that provides real-time isotopic identification, including neutron detectors to interdict Weapons of Mass Destruction (WMD) and radiation dispersion devices (RDD). The scissor lift will lower the detectors to within a foot off the ground and raise them to approximately 24 feet (7.3 m) in the air, allowing a wide vertical scanning range.

  9. Portable Multiplex Pathogen Detector

    SciTech Connect

    Visuri, S; McBride, M T; Matthews, D; Rao, R

    2002-07-15

    Tumor marker concentrations in serum provide useful information regarding clinical stage and prognosis of cancer and can thus be used for presymptomatic diagnostic purposes. Currently, detection and identification of soluble analytes in biological fluids is conducted by methods including bioassays, ELISA, PCR, DNA chip or strip tests. While these technologies are generally sensitive and specific, they are time consuming, labor intensive and cannot be multiplexed. Our goal is to develop a simple, point-of-care, portable, liquid array-based immunoassay device capable of simultaneous detection of a variety of cancer markers. Here we describe the development of assays for the detection of Serum Prostate Specific Antigen, and Ovalbumin from a single sample. The multiplexed immunoassays utilize polystyrene microbeads. The beads are imbedded with precise ratios of red and orange fluorescent dyes yielding an array of 100 beads, each with a unique spectral address (Figure 1). Each bead can be coated with capture antibodies specific for a given antigen. After antigen capture, secondary antibodies sandwich the bound antigen and are indirectly labeled by the fluorescent reporter phycoerythrin (PE). Each optically encoded and fluorescently-labeled microbead is then individually interrogated. A red laser excites the dye molecules imbedded inside the bead and classifies the bead to its unique bead set, and a green laser quantifies the assay at the bead surface. This technology has been proven to be comparable to the ELISA in terms of sensitivity and specificity. We also describe the laser-based instrumentation used to acquire fluorescent bead images Following the assay, droplets of bead suspension containing a mixture of bead classes were deposited onto filters held in place by a disposable plexiglass device and the resultant arrays viewed under the fluorescent imaging setup. Using the appropriate filter sets to extract the necessary red, orange and green fluorescence from the

  10. Portable Source Identification Device

    SciTech Connect

    Andersen, Eric S.; Samuel, Todd J.; Gervais, Kevin L.

    2005-08-01

    U.S. Customs and Border Protection (CBP) is the primary enforcement agency protecting the nation’s ports of entry. CBP is enhancing its capability to interdict the illicit import of nuclear and radiological materials and devices that may be used by terrorists. Pacific Northwest National Laboratory (PNNL) is providing scientific and technical support to CBP in their goal to enable rapid deployment of nuclear and radiation detection systems at U. S. ports of entry to monitor 100% of the incoming international traffic and cargo while not adversely impacting the operations or throughput of the ports. As the deployment of radiation detection systems proceeds, there is a need to adapt the baseline radiation portal monitor (RPM) system technology to operations at these diverse ports of entry. When screening produces an alarm in the primary inspection RPM, the alarming vehicle is removed from the flow of commerce and the alarm is typically confirmed in a secondary inspection RPM. The portable source identification device (PSID) is a radiation sensor panel (RSP), based on thallium-doped sodium iodide (NaI(Tl)) scintillation detector and gamma spectroscopic analysis hardware and software, mounted on a scissor lift on a small truck. The lift supports a box containing a commercial off-the-shelf (COTS) sodium iodide detector that provides real-time isotopic identification, including neutron detectors to interdict Weapons of Mass Destruction (WMD) and radiation dispersion devices (RDD). The scissor lift will lower the detectors to within a foot off the ground and raise them to approximately 24 feet in the air, allowing a wide vertical scanning range.

  11. Microchip micellar electrokinetic chromatography separation of alkaloids with UV-absorbance spectral detection.

    PubMed

    Newman, Carl I D; Giordano, Braden C; Copper, Christine L; Collins, Greg E

    2008-02-01

    A microchip device is demonstrated for the electrophoretic separation and UV-absorbance spectral detection of four toxic alkaloids: colchicine, aconitine, strychnine, and nicotine. A fused-silica (quartz) microchip containing a simple cross geometry is utilized to perform the separations, and a miniature, fiber-optic CCD spectrometer is coupled to the microchip for detection. Sensitive UV-absorbance detection is achieved via the application of online preconcentration techniques in combination with the quartz microchip substrate which contains an etched bubble-cell for increased pathlength. The miniature CCD spectrometer is configured to detect light between 190 and 645 nm and LabView programming written in-house enables absorbance spectra as well as separations to be monitored from 210 to 400 nm. Consequently, the configuration of this microchip device facilitates qualitative and quantitative separations via simultaneous spatial and spectral resolution of solutes. UV-absorbance limits of quantification for colchicine, 20 microM (8 mg/L); strychnine, 50 microM (17 mg/L); aconitine, 50 microM (32 mg/L); and nicotine, 100 microM (16 mg/L) are demonstrated on the microchip. With the exception of aconitine, these concentrations are > or =20-times more sensitive than lethal dose monitoring requirements. Finally, this device is demonstrated to successfully detect each toxin in water, skim milk, and apple juice samples spiked at sublethal dose concentrations after a simple, SPE procedure. PMID:18203247

  12. On-chip immunoassay of a cardiac biomarker in serum using a polyester-toner microchip.

    PubMed

    Kim, Ah Rahn; Kim, Joo Yeon; Choi, Kihwan; Chung, Doo Soo

    2013-05-15

    An on-chip immunoassay to detect C-reactive protein (CRP) was performed using a polyester-toner (PT) microchip. CRP is a highly conserved plasma protein responding to inflammation and is used for clinical purposes to diagnose an inflammatory state. For rapid analysis and specific interactions in immunoassays, extensive studies using microfluidic chips have been carried out. Recently, a simple technique to fabricate a disposable PT microchip by a direct printing process was developed and several applications were introduced. One major drawback of the PT microchip, however, is the poor separation performance due to the quality of the microfluidic structures. This problem for a PT microchip can be overcome using a cleavable tag immunoassay, which requires minimal separation performance. After analytes are conjugated onto antibodies which are immobilized on the surface of microbeads placed on the PT microchip, a second group of fluorescently tagged antibodies are added and complexed with the analytes. The tag is then cleaved and the solution containing the cleaved tag is analyzed by electrophoresis. The time needed for the complete analysis to be carried out on a PT microchip was less than 35 min. The dynamic range of the CRP in 10-fold diluted serum was 0.3-100 mg/L and the limit of detection was 0.3 mg/L, which demonstrated the possibility of a quantitative analysis of CRP in serum in clinical trials.

  13. Analysis of acrylamide in food products by microchip electrophoresis with on-line multiple-preconcentration techniques.

    PubMed

    Wu, Minglei; Chen, Wujuan; Wang, Guan; He, Pingang; Wang, Qingjiang

    2016-10-15

    In this paper, a microchip electrophoresis method based on on-line multiple-preconcentration techniques combining field-amplified sample stacking and reversed-field stacking was developed for highly efficient analysis of acrylamide in food products. The related mechanism as well as important parameters governing separation and preconcentration have been investigated in order to obtain maximum resolution and sensitivity. The best separation was achieved using a 100mM borate solution at pH 9.3 as running buffer, and a sensitivity enhancement factor of 432 was obtained using this concentration method under optimal conditions. The detection limit of acrylamide was 1ng/mL, which was comparable to those previously obtained using CE methods with on-line preconcentration techniques and was 41-700 times lower than those previously reported CE methods without concentration process. The proposed method also gave satisfactory and reliable results in the analysis of acrylamide in potato chips and French fries.

  14. [Infrared fluorescent markers for microarray DNA analysis on biological microchip].

    PubMed

    Spitsyn, M A; Shershov, V E; Kuznetsova, V E; Barsky, V E; Egorov, E E; Emelyanova, M A; Kreindlin, E Ya; Lysov, Yu P; Guseinov, T O; Fesenko, D E; Lapa, S A; Surzhikov, S A; Abramov, I S; Nasedkina, T V; Zasedatelev, A S; Chudinov, A V

    2015-01-01

    To expand the informational capabilities of molecular genetic research, on the biological microchips, new indotricarbocyanine dyes that fluoresce in the near infrared (IR) spectral region have been synthesized. The developed IR dyes were studied using a biochip-based test system for detection of mutations in the BRCA1/BRCA2 and CHECK2 genes associated with breast cancer. The fluorescent label was introduced to the analyzed DNA during PCR using primers labeled with the synthesized IR dyes. An analyzer that allows recording and processing of images of fluorescent microarrays in the IR spectral region was designed and manufactured. It has been shown that the use of the synthesized dyes enables to conduct analysis in the IR region and improve the reliability of medical diagnostic tests due to low fluorescence intensity of sample components as well as of a biochip substrate and the reagents used for analysis. PMID:26510593

  15. Microchip for the Measurement of Seebeck Coefficients of Single Nanowires

    NASA Astrophysics Data System (ADS)

    Völklein, F.; Schmitt, M.; Cornelius, T. W.; Picht, O.; Müller, S.; Neumann, R.

    2009-07-01

    Bismuth nanowires were electrochemically grown in ion track-etched polycarbonate membranes. Micromachining and microlithography were employed to realize a newly developed microchip for Seebeck coefficient measurements on individual nanowires. By anisotropic etching of a (100) Si wafer, an 800-nm-thick SiO2/Si3N4 membrane was prepared in the chip center. The low thermal conductivity of the membrane is crucial to obtain the required temperature difference Δ T along the nanowire. The wire is electrically contacted to thin metal pads which are patterned by a new method of microscopic exposure of photoresist and a lift-off process. A Δ T between the two pairs of contact pads, located on the membrane, is established by a thin-film heater. Applying the known Seebeck coefficient of a reference film, the temperature difference at this gap is determined. Using Δ T and the measured Seebeck voltage U of the nanowire, its Seebeck coefficient can be calculated.

  16. Microchip capillary electrophoresis based electroanalysis of triazine herbicides.

    PubMed

    Islam, Kamrul; Chand, Rohit; Han, Dawoon; Kim, Yong-Sang

    2015-01-01

    The number of pesticides used in agriculture is increasing steadily, leading to contamination of soil and drinking water. Herein, we present a microfluidic platform to detect the extent of contamination in soil samples. A microchip capillary electrophoresis system with in-channel electrodes was fabricated for label-free electroanalytical detection of triazine herbicides. The sample mixture contained three representative triazines: simazine, atrazine and ametryn. The electropherogram for each individual injection of simazine, atrazine and ametryn showed peaks at 58, 66 and 72 s whereas a mixture of them showed distinct peaks at 59, 67 and 71 s respectively. The technique as such may prove to be a useful qualitative and quantitative tool for the similar environmental pollutants.

  17. Investigation of temperature effect on cell mechanics by optofluidic microchips

    PubMed Central

    Yang, Tie; Nava, Giovanni; Minzioni, Paolo; Veglione, Manuela; Bragheri, Francesca; Lelii, Francesca Demetra; Vazquez, Rebeca Martinez; Osellame, Roberto; Cristiani, Ilaria

    2015-01-01

    Here we present the results of a study concerning the effect of temperature on cell mechanical properties. Two different optofluidic microchips with external temperature control are used to investigate the temperature-induced changes of highly metastatic human melanoma cells (A375MC2) in the range of ~0 – 35 °C. By means of an integrated optical stretcher, we observe that cells’ optical deformability is strongly enhanced by increasing cell and buffer-fluid temperature. This finding is supported by the results obtained from a second device, which probes the cells’ ability to be squeezed through a constriction. Measured data demonstrate a marked dependence of cell mechanical properties on temperature, thus highlighting the importance of including a proper temperature-control system in the experimental apparatus. PMID:26309762

  18. Vacuum membrane distillation by microchip with temperature gradient.

    PubMed

    Zhang, Yaopeng; Kato, Shinji; Anazawa, Takanori

    2010-04-01

    A multilayered microchip (25 x 95 mm) used for vacuum distillation is designed, fabricated and tested by rectification of a water-methanol mixture. The polymer chip employs a cooling channel to generate a temperature gradient along a distillation channel below, which is separated into a channel (72 microm deep) for liquid phase and a channel (72 microm deep) for vapor phase by an incorporated microporous poly(tetrafluoroethylene) (PTFE) membrane. The temperature gradient is controlled by adjusting hotplate temperature and flow rate of cooling water to make the temperatures in the stripping section higher than the increasing boiling points of the water-enriched liquids and the temperatures in the rectifying section lower than the decreasing dew points of the methanol-enriched vapors. The effects of temperature gradient, feed composition, feed flow rate and membrane pore size on the micro distillation are also investigated. A theoretical plate number up to 1.8 is achieved at the optimum conditions. PMID:20300677

  19. PMMA-based capillary electrophoresis electrochemical detection microchip fabrication

    NASA Astrophysics Data System (ADS)

    Horng, Ray-Hua; Han, Pin; Chen, Hung-Yu; Lin, Kuan-Wen; Tsai, Tung-Mung; Zen, Jyh-Myng

    2005-01-01

    In this paper, a 50 µm (depth) × 50 µm (width) microfluidic channel is made on a poly(methyl methacrylate) (PMMA) substrate using thick photoresist. Openings were drilled for buffer reservoirs on an additional piece of PMMA. A final PMMA/patterned photoresist/PMMA sandwich configuration was completed using a bonding process. The thick photoresist was used as the adhesion layer and also as the microfluidic system. Using screen-printed technology for carbon and silver electrode fabrication, the microchip electrophoretic device functions were demonstrated. Successful detection of uric acid and L-ascorbic acid (the main components in human urine) validates the functionality of the proposed system. Successful ascorbic and uric acid separation in a sample from a urine donor who had consumed 500 mg of vitamins verified the proposed biochip.

  20. [Infrared fluorescent markers for microarray DNA analysis on biological microchip].

    PubMed

    Spitsyn, M A; Shershov, V E; Kuznetsova, V E; Barsky, V E; Egorov, E E; Emelyanova, M A; Kreindlin, E Ya; Lysov, Yu P; Guseinov, T O; Fesenko, D E; Lapa, S A; Surzhikov, S A; Abramov, I S; Nasedkina, T V; Zasedatelev, A S; Chudinov, A V

    2015-01-01

    To expand the informational capabilities of molecular genetic research, on the biological microchips, new indotricarbocyanine dyes that fluoresce in the near infrared (IR) spectral region have been synthesized. The developed IR dyes were studied using a biochip-based test system for detection of mutations in the BRCA1/BRCA2 and CHECK2 genes associated with breast cancer. The fluorescent label was introduced to the analyzed DNA during PCR using primers labeled with the synthesized IR dyes. An analyzer that allows recording and processing of images of fluorescent microarrays in the IR spectral region was designed and manufactured. It has been shown that the use of the synthesized dyes enables to conduct analysis in the IR region and improve the reliability of medical diagnostic tests due to low fluorescence intensity of sample components as well as of a biochip substrate and the reagents used for analysis.

  1. Electrothermally activated microchips for implantable drug delivery and biosensing.

    PubMed

    Maloney, John M; Uhland, Scott A; Polito, Benjamin F; Sheppard, Norman F; Pelta, Christina M; Santini, John T

    2005-12-01

    Novel drug delivery and biosensing devices have the potential to increase the efficacy of drug therapy by providing physicians and patients the ability to precisely control key therapy parameters. Such "intelligent" systems can enable control of dose amount and the time, rate, and location of drug delivery. We have developed and demonstrated the operation of an electrothermal mechanism to precisely control the delivery of drugs and exposure of biosensors. These microchip devices contain an array of individually sealed and actuated reservoirs, each capped by a thin metal membrane comprised of either gold or multiple layers of titanium and platinum. The passage of a threshold level of electric current through the membrane causes it to disintegrate, thereby exposing the protected contents (drugs or biosensors) of the reservoir to the surrounding environment. This paper describes the theory and experimental characterization of the electrothermal method and includes in vitro release results for a model compound.

  2. Investigation of temperature effect on cell mechanics by optofluidic microchips.

    PubMed

    Yang, Tie; Nava, Giovanni; Minzioni, Paolo; Veglione, Manuela; Bragheri, Francesca; Lelii, Francesca Demetra; Vazquez, Rebeca Martinez; Osellame, Roberto; Cristiani, Ilaria

    2015-08-01

    Here we present the results of a study concerning the effect of temperature on cell mechanical properties. Two different optofluidic microchips with external temperature control are used to investigate the temperature-induced changes of highly metastatic human melanoma cells (A375MC2) in the range of ~0 - 35 °C. By means of an integrated optical stretcher, we observe that cells' optical deformability is strongly enhanced by increasing cell and buffer-fluid temperature. This finding is supported by the results obtained from a second device, which probes the cells' ability to be squeezed through a constriction. Measured data demonstrate a marked dependence of cell mechanical properties on temperature, thus highlighting the importance of including a proper temperature-control system in the experimental apparatus.

  3. Affinity Monolith-Integrated Microchips for Protein Purification and Concentration.

    PubMed

    Gao, Changlu; Sun, Xiuhua; Wang, Huaixin; Qiao, Wei; Hu, Bo

    2016-01-01

    Affinity chromatography is a valuable method to purify and concentrate minute amount of proteins. Monoliths with epoxy groups for affinity immobilization were prepared by direct in-situ photopolymerization of glycidyl methacrylate and ethylene glycol dimethacrylate in porogenic solvents consisting of 1-dodecanol and cyclohexanol. By integrating affinity monoliths onto a microfluidic system, targeted biomolecules can be captured and retained on affinity column, while other biomolecules having no specific interactions toward the immobilized ligands flow through the microchannel. Therefore, proteins which remain on the affinity column are purified and concentrated, and then eluted by appropriate solutions and finally, separated by microchip capillary electrophoresis. This integrated microfluidic device has been applied to the purification and separation of specific proteins (FITC-labeled human serum albumin and IgG) in a mixture.

  4. Affinity Monolith-Integrated Microchips for Protein Purification and Concentration.

    PubMed

    Gao, Changlu; Sun, Xiuhua; Wang, Huaixin; Qiao, Wei; Hu, Bo

    2016-01-01

    Affinity chromatography is a valuable method to purify and concentrate minute amount of proteins. Monoliths with epoxy groups for affinity immobilization were prepared by direct in-situ photopolymerization of glycidyl methacrylate and ethylene glycol dimethacrylate in porogenic solvents consisting of 1-dodecanol and cyclohexanol. By integrating affinity monoliths onto a microfluidic system, targeted biomolecules can be captured and retained on affinity column, while other biomolecules having no specific interactions toward the immobilized ligands flow through the microchannel. Therefore, proteins which remain on the affinity column are purified and concentrated, and then eluted by appropriate solutions and finally, separated by microchip capillary electrophoresis. This integrated microfluidic device has been applied to the purification and separation of specific proteins (FITC-labeled human serum albumin and IgG) in a mixture. PMID:27473483

  5. Accurate multiplex gene synthesis from programmable DNA microchips

    NASA Astrophysics Data System (ADS)

    Tian, Jingdong; Gong, Hui; Sheng, Nijing; Zhou, Xiaochuan; Gulari, Erdogan; Gao, Xiaolian; Church, George

    2004-12-01

    Testing the many hypotheses from genomics and systems biology experiments demands accurate and cost-effective gene and genome synthesis. Here we describe a microchip-based technology for multiplex gene synthesis. Pools of thousands of `construction' oligonucleotides and tagged complementary `selection' oligonucleotides are synthesized on photo-programmable microfluidic chips, released, amplified and selected by hybridization to reduce synthesis errors ninefold. A one-step polymerase assembly multiplexing reaction assembles these into multiple genes. This technology enabled us to synthesize all 21 genes that encode the proteins of the Escherichia coli 30S ribosomal subunit, and to optimize their translation efficiency in vitro through alteration of codon bias. This is a significant step towards the synthesis of ribosomes in vitro and should have utility for synthetic biology in general.

  6. Improving sensitivity for microchip electrophoresis interfaced with inductively coupled plasma mass spectrometry using parallel multichannel separation.

    PubMed

    Cheng, Heyong; Liu, Jinhua; Xu, Zigang; Wang, Yuanchao; Ye, Meiying

    2016-08-26

    We reported sensitivity enhancement using multichannel parallel separation for microchip electrophoresis hyphenated with inductively coupled plasma mass spectrometry (MCE-ICP-MS) in this study. By using 2-20 array lanes for parallel separation, the sensitivity of the MCE-ICP-MS system was proportionally improved by 2-20 folds. No significantly adverse effect of parallel separation on column efficiency and resolution was observed. Rapid separation of Hg(2+) and methylmercuric (MeHg) ion within 36s under an electric field of 800Vcm(-1) was achieved in the 2-cm twenty-channels with a background electrolyte of 5mmolL(-1) borate buffer (pH 9.2). Detection limits of Hg(2+) and MeHg by the proposed system were decreased to 6.8-7.1ngL(-1). Good agreement between determined values and certified values of a certified reference fish was obtained with recoveries ranged between 94-98%. All results prove its advantages including high sensitivity, high efficiency and low operation cost, which are beneficial to routine analysis of metal speciation in environmental, biological and food fields. PMID:27488720

  7. Portable Habitat for Antarctic Scientific Research (PHASR)

    NASA Technical Reports Server (NTRS)

    Griswold, Samantha S.

    1992-01-01

    The Portable Habitat for Antarctic Scientific Research, PHASR, is designed as a versatile, general purpose habitat system that addresses the problem of functional space and environmental soundness in a partially fabric-covered shelter. PHASR is used for remote field site applications that can be quickly deployed. PHASR will also provide four scientists with a comfortable and efficient use of interior space. PHASR is a NASA/USRA Advanced Design Program project conducted at the University of Houston College of Architecture, Sasadawa International Center for Space Architecture (SICSA). This report is prepared for NASA/USRA.

  8. A portable free space optical system

    NASA Astrophysics Data System (ADS)

    Ai, Yong; Lu, Xingguang; Yang, Jinglin; Chen, Jing; Hao, Zhonggang

    2005-08-01

    A portable protocol independent free space optical communication terminal was developed, which enables customer to quickly deploy optical bandwidth services for applications such as fiber extension, wild field point to point communication and wireless backhaul while avoiding costly and time-consuming fiber installation. By using specially designed optical components and optical-mechanical structure, the system is very compact and effective, can establish optical link within a few minutes, with total weight 4kg, size 160 x 360 x 155 mm, effective transmitting/receiving aperture 40mm, data rate 100Mbps, maximum communication distance 1500m. The system and experiments are presented in the paper.

  9. Improved portable lighting for visual aircraft inspection

    SciTech Connect

    Shagam, R.N.; Lerner, J.; Shie, R.

    1995-04-01

    The most common tool used by aircraft inspectors is the personal flashlight. While it is compact and very portable, it is generally typified by poor beam quality which can interfere with the ability for an inspector to detect small defects and anomalies, such as cracks and corrosion sites, which may be indicators of major structural problems. A Light Shaping Diffuser{trademark} (LSD) installed in a stock flashlight as a replacement to the lens can improve the uniformity of an average flashlight and improve the quality of the inspection. Field trials at aircraft maintenance facilities have demonstrated general acceptance of the LSD by aircraft inspection and maintenance personnel.

  10. [Portable instrument for arteriosclerosis assessment].

    PubMed

    Cao, Shuai; Chen, Xiang

    2014-01-01

    A portable instrument for arteriosclerosis assessment containing sensor module, acquisition board and embedded module was developed for home care in this paper. The sensor module consists of one ECG module and three pulse wave extraction modules, synchronously acquiring human ECG and pulse wave signal of carotid, radial, and dorsal, respectively. The acquisition board converts the sensor module's analog output signals into digital signals and transmits them to the embedded module. The embedded module realizes the functions including signal display, storage and the calculation and output of pulse wave velocity. The structure of the proposed portable instrument is simple, easy to use, and easy to expand. Small size, low cost, and low power consumption are also the advantages of this device. Experimental results demonstrated that the proposed portable instrument for arteriosclerosis assessment has high accuracy, good repeatability and can assess the degree of atherosclerosis appropriately.

  11. 20 T portable bipolar magnetic pulser.

    PubMed

    Wolf Cruz, R R; Dias, A L B; Bonfim, M J C

    2010-06-01

    High magnetic fields are required for the study of hard magnetic materials and, in many cases, the reversal of these fields is essential. This paper describes a portable pulse generator capable of producing bipolar magnetic fields up to 20 T into a copper coil. The peak current around 7 kA is achieved by discharging two capacitor banks through a combination of thyristors and fast diodes. Each pulse polarity has a semisinusoidal shape with 18 mus base width. Pulse triggering is computer controlled and magnetic measurements are done by an induction coil or Kerr effect acquired by a sampling oscilloscope. The whole apparatus weighs less than 2 kg. Hysteresis loops of NdFeB magnets were done to demonstrate the viability of the system.

  12. Freely oriented portable superconducting magnet

    SciTech Connect

    Schmierer, Eric N.; Prenger, F. Coyne; Hill, Dallas D.

    2010-01-12

    A freely oriented portable superconducting magnet is disclosed. Coolant is supplied to the superconducting magnet from a repository separate from the magnet, enabling portability of the magnet. A plurality of support assemblies structurally anchor and thermally isolate the magnet within a thermal shield. A plurality of support assemblies structurally anchor and thermally isolate the thermal shield within a vacuum vessel. The support assemblies restrain movement of the magnet resulting from energizing and cooldown, as well as from changes in orientation, enabling the magnet to be freely orientable.

  13. Portable Heat Pump Testing Device

    NASA Astrophysics Data System (ADS)

    Kłosowiak, R.; Bartoszewicz, J.; Urbaniak, R.

    2015-08-01

    The aim of this paper is to present the design and working principle of a portable testing device for heat pumps in the energy recirculation system. The presented test stand can be used for any refrigerating/reverse flow cycle device to calculate the device energy balance. The equipment is made of two portable containers of the capacity of 250 liters to simulate the air heat source and ground heat source with a system of temperature stabilization, compressor heat pump of the coefficient of performance (COP) of = 4.3, a failsafe system and a control and measurement system.

  14. A Compact, Microchip-Based, Atomic Clock Based on Ultracold Trapped Rb Atoms

    NASA Astrophysics Data System (ADS)

    Farkas, Daniel; Zozulya, Alex; Anderson, Dana

    2010-03-01

    We propose a compact atomic clock based on ultracold Rb atoms that are magnetically trapped near the surface of an atom microchip. An interrogation scheme that combines electromagnetically-induced transparency (EIT) with Ramsey's method of separated oscillatory fields can achieve atomic shot-noise level performance of 10-13/τ^1/2 for 10^6 atoms and an interrogation time of 1 s. A two-color Mach-Zehnder interferometer can detect a 100 pW probe beam at the optical shot-noise level using conventional photodetectors. This measurement scheme is non-destructive and therefore can be used to increase operational duty cycle by reusing the trapped atoms between clock cycles. Numerical calculations of the density matrix equations are used to identify realistic operating parameters at which AC Stark shifts are eliminated. By considering fluctuations in these parameters, we estimate that AC Stark shifts can be canceled to a level better than 2x10-14.

  15. Electroporation on microchips: the harmful effects of pH changes and scaling down

    PubMed Central

    Li, Yang; Wu, Mengxi; Zhao, Deyao; Wei, Zewen; Zhong, Wenfeng; Wang, Xiaoxia; Liang, Zicai; Li, Zhihong

    2015-01-01

    Electroporation has been widely used in delivering foreign biomolecules into cells, but there is still much room for improvement, such as cell viability and integrity. In this manuscript, we investigate the distribution and the toxicity of pH changes during electroporation, which significantly decreases cell viability. A localized pH gradient forms between anode and cathode leading to a localized distribution of cell death near the electrodes, especially cathodes. The toxicity of hydroxyl ions is severe and acute due to their effect in the decomposition of phospholipid bilayer membrane. On the other hand, the electric field used for electroporation aggravates the toxicity of hydroxyl because the electropermeabilization of cell membrane makes bilayer structure more loosen and vulnerable. We also investigate the side effects during scaling down the size of electrodes in electroporation microchips. Higher percentage of cells is damaged when the size of electrodes is smaller. At last, we propose an effective strategy to constrain the change of pH by modifying the composition of electroporation buffer. The modified buffer decreases the changes of pH, thus enables high cell viability even when the electric pulse duration exceeds several milliseconds. This ability has potential advantage in some applications that require long-time electric pulse stimulation. PMID:26658168

  16. Recent innovations in protein separation on microchips by electrophoretic methods: an update.

    PubMed

    Tran, Nguyet Thuy; Ayed, Ichraf; Pallandre, Antoine; Taverna, Myriam

    2010-01-01

    Lab-on-a-chip electrophoresis is becoming increasingly useful for protein analysis, thanks to recent developments in this field. This review is an update of the review we published at the start of 2008 [Peng, Y., Pallandre, A., Tran, N. T., Taverna, M., Electrophoresis 2008, 29, 156-177]. The superiority of polymers for the manufacture of analytical microchips has been confirmed. This trend implies several modifications to the processes previously used with glass/silicon chips and requires a better understanding of the interfacial phenomena of these materials. Significant progress in chip-based techniques for protein analysis has been made in the last 2 years. In addition to advances in traditional electrokinetic modes, counter-flow gradient focusing techniques have emerged as useful methods not only for separation, but also for the online preconcentration of samples. This review, with more than 175 references, presents recent advances and novel strategies for EOF measurement, surface treatment, sample pretreatment, detection and innovations relating to the different modes of separation. PMID:20014053

  17. Electroporation on microchips: the harmful effects of pH changes and scaling down.

    PubMed

    Li, Yang; Wu, Mengxi; Zhao, Deyao; Wei, Zewen; Zhong, Wenfeng; Wang, Xiaoxia; Liang, Zicai; Li, Zhihong

    2015-12-14

    Electroporation has been widely used in delivering foreign biomolecules into cells, but there is still much room for improvement, such as cell viability and integrity. In this manuscript, we investigate the distribution and the toxicity of pH changes during electroporation, which significantly decreases cell viability. A localized pH gradient forms between anode and cathode leading to a localized distribution of cell death near the electrodes, especially cathodes. The toxicity of hydroxyl ions is severe and acute due to their effect in the decomposition of phospholipid bilayer membrane. On the other hand, the electric field used for electroporation aggravates the toxicity of hydroxyl because the electropermeabilization of cell membrane makes bilayer structure more loosen and vulnerable. We also investigate the side effects during scaling down the size of electrodes in electroporation microchips. Higher percentage of cells is damaged when the size of electrodes is smaller. At last, we propose an effective strategy to constrain the change of pH by modifying the composition of electroporation buffer. The modified buffer decreases the changes of pH, thus enables high cell viability even when the electric pulse duration exceeds several milliseconds. This ability has potential advantage in some applications that require long-time electric pulse stimulation.

  18. Microdissection, microchip arrays, and molecular analysis of tumor cells (primary and metastases).

    PubMed

    Pappalardo, P A; Bonner, R; Krizman, D B; Emmert-Buck, M R; Liotta, L A

    1998-07-01

    Advances in biotechnology and bioinformatics are offering promise for new breakthroughs in gene discovery and elucidation of gene function. At present, many candidate genes related to cancer pathogenesis have been identified in several types of human cancer, yet frequently their function remains elusive. This is particularly true as it relates to the progression of human cancer. This landscape could change dramatically, however, as technological innovations and improvements continue to revolutionize these fields. High-throughput molecular approaches are emerging, which may become accurate, automated, and cost-effective. For example, DNA arrays on microchips are under development with numerous applications, including the ability to screen genes rapidly for mutations and to study patterns of gene expression on a large scale. Automated systems for microdissection and sequencing are also in their implementation stages. Commensurate with their integration and evolution, these information and technological tools have the potential to offer a more comprehensive understanding of multiple genetic and cellular alterations occurring during cancer initiation, development, and progression. Ultimately, this fundamental knowledge can provide strategies for intervention, prevention, and early diagnosis. This is a US government work. There are no restrictions on its use.

  19. 48 CFR 1837.170 - Pension portability.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... portability. (a) It is NASA's policy not to require pension portability in service contracts. However, pension... procurement officer determines in writing, with full supporting rationale, that such a requirement is in...

  20. Identification of chemical warfare agents from vapor samples using a field-portable capillary gas chromatography/membrane-interfaced electron ionization quadrupole mass spectrometry instrument with Tri-Bed concentrator.

    PubMed

    Nagashima, Hisayuki; Kondo, Tomohide; Nagoya, Tomoki; Ikeda, Toru; Kurimata, Naoko; Unoke, Shohei; Seto, Yasuo

    2015-08-01

    A field-portable gas chromatograph-mass spectrometer (Hapsite ER system) was evaluated for the detection of chemical warfare agents (CWAs) in the vapor phase. The system consisted of Tri-Bed concentrator gas sampler (trapping time: 3s(-1)min), a nonpolar low thermal-mass capillary gas chromatography column capable of raising temperatures up to 200°C, a hydrophobic membrane-interfaced electron ionization quadrupole mass spectrometer evacuated by a non-evaporative getter pump for data acquisition, and a personal computer for data analysis. Sample vapors containing as little as 22μg sarin (GB), 100μg soman (GD), 210μg tabun (GA), 55μg cyclohexylsarin (GF), 4.8μg sulfur mustard, 390μg nitrogen mustard 1, 140μg of nitrogen mustard 2, 130μg nitrogen mustard 3, 120μg of 2-chloroacetophenone and 990μg of chloropicrin per cubic meter could be confirmed after Tri-Bed micro-concentration (for 1min) and automated AMDIS search within 12min. Using manual deconvolution by background subtraction of neighboring regions on the extracted ion chromatograms, the above-mentioned CWAs could be confirmed at lower concentration levels. The memory effects were also examined and we found that blister agents showed significantly more carry-over than nerve agents. Gasoline vapor was found to interfere with the detection of GB and GD, raising the concentration limits for confirmation in the presence of gasoline by both AMDIS search and manual deconvolution; however, GA and GF were not subject to interference by gasoline. Lewisite 1, and o-chlorobenzylidene malononitrile could also be confirmed by gas chromatography, but it was hard to quantify them. Vapors of phosgene, chlorine, and cyanogen chloride could be confirmed by direct mass spectrometric detection at concentration levels higher than 2, 140, and 10mg/m(3) respectively, by bypassing the micro-concentration trap and gas chromatographic separation. PMID:26118803

  1. Use of a Field Portable X-Ray Fluorescence Analyzer for Environmental Exposure Assessment of a Neighborhood in Cairo, Egypt Adjacent to the Site of a Former Secondary Lead Smelter.

    PubMed

    Menrath, William; Zakaria, Yehia; El-Safty, Amal; Clark, C Scott; Roda, Sandy M; Elsayed, Essam; Lind, Caroline; Pesce, John; Peng, Hongying

    2015-01-01

    The objectives of this study are to demonstrate for the first time the use of a field portable X-Ray Fluorescence Analyzer (XRF) in a multi-media environmental survey and to use the survey results to determine if residual lead from a once-active secondary lead smelter in Cairo, Egypt, still posed a health risk to the residents when comparing results with US EPA standards. Results were analyzed to determine if relationships among the variables indicated that there were residual impacts of the former smelter. Samples collected inside and near a total of 194 dwellings were analyzed. The mean floor dust lead loading was 7.48 μg lead/ft(2). Almost 10% of the dwellings had at least one floor dust wipe sample that exceeded the United States Environmental Protection Agency's (USEPA) interior settled dust lead level of 40 μg lead/ft(2). The median paint lead level was 0.04 mg lead/cm(2). 17% of the dwellings had at least one interior paint sample that exceeded the USEPA standard of 1.0 mg lead/cm(2). Mean soil lead concentration in the study area was 458 ppm and 91 ppm outside the study area. Four of nine composite soil samples exceeded the US EPA limit for bare soil in play areas. Lead concentrations in samples collected in locations outside the study area did not exceed the limit. The highest concentration was in the plot closest to the smelter and may represent residual impact from the former smelter. Statistically significant relationships were not detected between interior floor dust lead loading and either interior paint lead loading or exterior dust lead concentration. Thus, no significant exposure from the former smelter was indicated by these analyses. This may have resulted from the time elapsed since the closing of the smelter and/or the relatively low paint lead levels. Further study is needed in other areas of Egypt near former and active lead smelters. Elevated levels of mercury and arsenic detected in soil samples do not appear to be related to the smelter

  2. Identification of chemical warfare agents from vapor samples using a field-portable capillary gas chromatography/membrane-interfaced electron ionization quadrupole mass spectrometry instrument with Tri-Bed concentrator.

    PubMed

    Nagashima, Hisayuki; Kondo, Tomohide; Nagoya, Tomoki; Ikeda, Toru; Kurimata, Naoko; Unoke, Shohei; Seto, Yasuo

    2015-08-01

    A field-portable gas chromatograph-mass spectrometer (Hapsite ER system) was evaluated for the detection of chemical warfare agents (CWAs) in the vapor phase. The system consisted of Tri-Bed concentrator gas sampler (trapping time: 3s(-1)min), a nonpolar low thermal-mass capillary gas chromatography column capable of raising temperatures up to 200°C, a hydrophobic membrane-interfaced electron ionization quadrupole mass spectrometer evacuated by a non-evaporative getter pump for data acquisition, and a personal computer for data analysis. Sample vapors containing as little as 22μg sarin (GB), 100μg soman (GD), 210μg tabun (GA), 55μg cyclohexylsarin (GF), 4.8μg sulfur mustard, 390μg nitrogen mustard 1, 140μg of nitrogen mustard 2, 130μg nitrogen mustard 3, 120μg of 2-chloroacetophenone and 990μg of chloropicrin per cubic meter could be confirmed after Tri-Bed micro-concentration (for 1min) and automated AMDIS search within 12min. Using manual deconvolution by background subtraction of neighboring regions on the extracted ion chromatograms, the above-mentioned CWAs could be confirmed at lower concentration levels. The memory effects were also examined and we found that blister agents showed significantly more carry-over than nerve agents. Gasoline vapor was found to interfere with the detection of GB and GD, raising the concentration limits for confirmation in the presence of gasoline by both AMDIS search and manual deconvolution; however, GA and GF were not subject to interference by gasoline. Lewisite 1, and o-chlorobenzylidene malononitrile could also be confirmed by gas chromatography, but it was hard to quantify them. Vapors of phosgene, chlorine, and cyanogen chloride could be confirmed by direct mass spectrometric detection at concentration levels higher than 2, 140, and 10mg/m(3) respectively, by bypassing the micro-concentration trap and gas chromatographic separation.

  3. Use of a Field Portable X-Ray Fluorescence Analyzer for Environmental Exposure Assessment of a Neighborhood in Cairo, Egypt Adjacent to the Site of a Former Secondary Lead Smelter.

    PubMed

    Menrath, William; Zakaria, Yehia; El-Safty, Amal; Clark, C Scott; Roda, Sandy M; Elsayed, Essam; Lind, Caroline; Pesce, John; Peng, Hongying

    2015-01-01

    The objectives of this study are to demonstrate for the first time the use of a field portable X-Ray Fluorescence Analyzer (XRF) in a multi-media environmental survey and to use the survey results to determine if residual lead from a once-active secondary lead smelter in Cairo, Egypt, still posed a health risk to the residents when comparing results with US EPA standards. Results were analyzed to determine if relationships among the variables indicated that there were residual impacts of the former smelter. Samples collected inside and near a total of 194 dwellings were analyzed. The mean floor dust lead loading was 7.48 μg lead/ft(2). Almost 10% of the dwellings had at least one floor dust wipe sample that exceeded the United States Environmental Protection Agency's (USEPA) interior settled dust lead level of 40 μg lead/ft(2). The median paint lead level was 0.04 mg lead/cm(2). 17% of the dwellings had at least one interior paint sample that exceeded the USEPA standard of 1.0 mg lead/cm(2). Mean soil lead concentration in the study area was 458 ppm and 91 ppm outside the study area. Four of nine composite soil samples exceeded the US EPA limit for bare soil in play areas. Lead concentrations in samples collected in locations outside the study area did not exceed the limit. The highest concentration was in the plot closest to the smelter and may represent residual impact from the former smelter. Statistically significant relationships were not detected between interior floor dust lead loading and either interior paint lead loading or exterior dust lead concentration. Thus, no significant exposure from the former smelter was indicated by these analyses. This may have resulted from the time elapsed since the closing of the smelter and/or the relatively low paint lead levels. Further study is needed in other areas of Egypt near former and active lead smelters. Elevated levels of mercury and arsenic detected in soil samples do not appear to be related to the smelter

  4. Nonlinear multi-photon laser wave-mixing optical detection in microarrays and microchips for ultrasensitive detection and separation of biomarkers for cancer and neurodegenerative diseases

    NASA Astrophysics Data System (ADS)

    Iwabuchi, Manna; Hetu, Marcel; Maxwell, Eric; Pradel, Jean S.; Ramos, Sashary; Tong, William G.

    2015-09-01

    Multi-photon degenerate four-wave mixing is demonstrated as an ultrasensitive absorption-based optical method for detection, separation and identification of biomarker proteins in the development of early diagnostic methods for HIV- 1, cancer and neurodegenerative diseases using compact, portable microarrays and capillary- or microchip-based chemical separation systems that offer high chemical specificity levels. The wave-mixing signal has a quadratic dependence on concentration, and hence, it allows more reliable monitoring of smaller changes in analyte properties. Our wave-mixing detection sensitivity is comparable or better than those of current methods including enzyme-linked immunoassay for clinical diagnostic and screening. Detection sensitivity is excellent since the wave-mixing signal is a coherent laser-like beam that can be collected with virtually 100% collection efficiency with high S/N. Our analysis time is short (1-15 minutes) for molecular weight-based protein separation as compared to that of a conventional separation technique, e.g., sodium dodecyl sulfate-polyacrylamide gel electrophoresis. When ultrasensitive wavemixing detection is paired with high-resolution capillary- or microchip-based separation systems, biomarkers can be separated and identified at the zepto- and yocto-mole levels for a wide range of analytes. Specific analytes can be captured in a microchannel through the use of antibody-antigen interactions that provide better chemical specificity as compared to size-based separation alone. The technique can also be combined with immune-precipitation and a multichannel capillary array for high-throughput analysis of more complex protein samples. Wave mixing allows the use of chromophores and absorption-modifying tags, in addition to conventional fluorophores, for online detection of immunecomplexes related to cancer.

  5. Portable File Format (PFF) specifications.

    SciTech Connect

    Dolan, Daniel H.,

    2015-02-01

    Created at Sandia National Laboratories, the Portable File Format (PFF) allows binary data transfer across computer platforms. Although this capability is supported by many other formats, PFF files are still in use at Sandia, particularly in pulsed power research. This report provides detailed PFF specifications for accessing data without relying on legacy code.

  6. Portable vacuum object handling device

    DOEpatents

    Anderson, Gordon H.

    1983-08-09

    The disclosure relates to a portable device adapted to handle objects which are not to be touched by hand. A piston and bore wall form a vacuum chamber communicating with an adaptor sealably engageable with an object to be lifted. The piston is manually moved and set to establish vacuum. A valve is manually actuatable to apply the vacuum to lift the object.

  7. Portable Positron Measurement System (PPMS)

    SciTech Connect

    2011-01-01

    Portable Positron Measurement System (PPMS) is an automated, non-destructive inspection system based on positron annihilation, which characterizes a material's in situatomic-level properties during the manufacturing processes of formation, solidification, and heat treatment. Simultaneous manufacturing and quality monitoring now are possible. Learn more about the lab's project on our facebook site http://www.facebook.com/idahonationallaboratory.

  8. Portable Positron Measurement System (PPMS)

    ScienceCinema

    None

    2016-07-12

    Portable Positron Measurement System (PPMS) is an automated, non-destructive inspection system based on positron annihilation, which characterizes a material's in situatomic-level properties during the manufacturing processes of formation, solidification, and heat treatment. Simultaneous manufacturing and quality monitoring now are possible. Learn more about the lab's project on our facebook site http://www.facebook.com/idahonationallaboratory.

  9. Portable thermo-powered high-throughput visual electrochemiluminescence sensor.

    PubMed

    Hao, Nan; Xiong, Meng; Zhang, Jia-dong; Xu, Jing-Juan; Chen, Hong-Yuan

    2013-12-17

    This paper describes a portable thermo-powered high-throughput visual electrochemiluminescence (ECL) sensor for the first time. This sensor is composed of a tiny power supply device based on thermal-electrical conversion and a facile prepared array electrode. The ECL detection could be conducted with thermo-power, which is easily accessible. For example, hot water, a bonfire, or a lighted candle enables the detection to be conducted. And the assay can be directly monitored by the naked eye semiquantitatively or smart phones quantitatively. Combined with transparent electrode and array microreactors, a portable high-throughput sensor was achieved. The portable device, avoiding the use of an electrochemical workstation to generate potential and a photomultiplier tube to receive the signal, is not only a valuable addition for traditional methods but also a suitable device for field operation or point-of-care testing. PMID:24215560

  10. Monolithic thermally bonded Er3+, Yb3+:glass/Co2+:MgAl2O4 microchip lasers

    NASA Astrophysics Data System (ADS)

    Mlynczak, Jaroslaw; Belghachem, Nabil

    2015-12-01

    The highest ever reported 10 kW peak power in monolithic thermally bonded Er3+, Yb3+:glass/Co2+:MgAl2O4 microchip laser was achieved. To show the superiority of monolithic microchip lasers over those with external mirrors the laser generation characteristics of the same samples in both cases were compared.

  11. Homogeneous agglutination assay based on micro-chip sheathless flow cytometry.

    PubMed

    Ma, Zengshuai; Zhang, Pan; Cheng, Yinuo; Xie, Shuai; Zhang, Shuai; Ye, Xiongying

    2015-11-01

    Homogeneous assays possess important advantages that no washing or physical separation is required, contributing to robust protocols and easy implementation which ensures potential point-of-care applications. Optimizing the detection strategy to reduce the number of reagents used and simplify the detection device is desirable. A method of homogeneous bead-agglutination assay based on micro-chip sheathless flow cytometry has been developed. The detection processes include mixing the capture-probe conjugated beads with an analyte containing sample, followed by flowing the reaction mixtures through the micro-chip sheathless flow cytometric device. The analyte concentrations were detected by counting the proportion of monomers in the reaction mixtures. Streptavidin-coated magnetic beads and biotinylated bovine serum albumin (bBSA) were used as a model system to verify the method, and detection limits of 0.15 pM and 1.5 pM for bBSA were achieved, using commercial Calibur and the developed micro-chip sheathless flow cytometric device, respectively. The setup of the micro-chip sheathless flow cytometric device is significantly simple; meanwhile, the system maintains relatively high sensitivity, which mainly benefits from the application of forward scattering to distinguish aggregates from monomers. The micro-chip sheathless flow cytometric device for bead agglutination detection provides us with a promising method for versatile immunoassays on microfluidic platforms.

  12. A Sol-Gel-Modified Poly(methyl methacrylate) Electrophoresis Microchip with a Hydrophilic Channel Wall

    SciTech Connect

    Chen, Gang; Xu, Xuejiao; Lin, Yuehe; Wang, Joseph

    2007-07-27

    A sol-gel method was employed to fabricate a poly(methyl methacrylate) (PMMA) electrophoresis microchip that contains a hydrophilic channel wall. To fabricate such a device, tetraethoxysilane (TEOS) was injected into the PMMA channel and was allowed to diffuse into the surface layer for 24 h. After removing the excess TEOS, the channel was filled with an acidic solution for 3 h. Subsequently, the channel was flushed with water and was pretreated in an oven to obtain a sol-gel-modified PMMA microchip. The water contact angle for the sol-gel-modified PMMA was 27.4° compared with 66.3° for the pure PMMA. In addition, the electro-osmotic flow increased from 2.13×10-4 cm2 V-1 s-1 for the native-PMMA channel to 4.86×10-4 cm2 V-1 s-1 for the modified one. The analytical performance of the sol-gel-modified PMMA microchip was demonstrated for the electrophoretic separation of several purines, coupled with amperometric detection. The separation efficiency of uric acid increased to 74 882.3 m-1 compared with 14 730.5 m-1 for native-PMMA microchips. The result of this simple modification is a significant improvement in the performance of PMMA for microchip electrophoresis and microfluidic applications.

  13. A high-speed, high-performance on-chip integrated reverse transcription (RT)-microchip.

    PubMed

    Lee, Hwanyong; Han, Nari; Choi, In-Hak; Han, Ki-Ho

    2013-02-01

    This report introduces an on-chip integrated reverse transcription (RT)-microchip, which includes two genetic functionalities of RNA extraction and cDNA synthesis. In the RNA extraction compartment, RNA is extracted from peripheral blood lysate within 1 min, by lateral magnetophoresis using magnetic oligo-dT beads. The extracted RNA is then collected and used directly to produce cDNA in the cDNA synthesis microchamber, which is monolithically integrated with the RNA extraction compartment. To verify the superiority of the proposed RT-microchip, RT-PCR amplification was performed using cDNA harvested from the RT-microchip, and the results were compared with those obtained using typical RNA extraction methods such as a silica matrix column and magnetic oligo-dT beads. The RT-PCR amplification results using 100 μl of blood showed that the intensity of the bands in gel electrophoresis of the RT-microchip was 2-fold stronger than that of the silica matrix column and 2.65-fold stronger than that of the magnetic oligo-dT beads. The results demonstrate that the RT-microchip technique is the most sensitive of the tested methods.

  14. 48 CFR 1837.170 - Pension portability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false Pension portability. 1837... ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING SERVICE CONTRACTING Service Contracts-General 1837.170 Pension portability. (a) It is NASA's policy not to require pension portability in service contracts. However,...

  15. 46 CFR 120.430 - Portable lights.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Portable lights. 120.430 Section 120.430 Shipping COAST... Systems § 120.430 Portable lights. Each vessel must be equipped with at least two operable portable battery lights. One of these lights must be located at the operating station and the other at the...

  16. 46 CFR 183.430 - Portable lights

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Portable lights 183.430 Section 183.430 Shipping COAST...) ELECTRICAL INSTALLATION Lighting Systems § 183.430 Portable lights Each vessel must be equipped with at least two operable portable battery lights. One of these lights must be located at the operating station...

  17. 46 CFR 120.430 - Portable lights.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Portable lights. 120.430 Section 120.430 Shipping COAST... Systems § 120.430 Portable lights. Each vessel must be equipped with at least two operable portable battery lights. One of these lights must be located at the operating station and the other at the...

  18. 46 CFR 183.430 - Portable lights

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Portable lights 183.430 Section 183.430 Shipping COAST...) ELECTRICAL INSTALLATION Lighting Systems § 183.430 Portable lights Each vessel must be equipped with at least two operable portable battery lights. One of these lights must be located at the operating station...

  19. 29 CFR 1917.119 - Portable ladders.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Portable ladders. 1917.119 Section 1917.119 Labor... (CONTINUED) MARINE TERMINALS Terminal Facilities § 1917.119 Portable ladders. (a) Scope and applicability. This section applies to all portable ladders, including job-made ladders for temporary use,...

  20. 29 CFR 1917.119 - Portable ladders.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Portable ladders. 1917.119 Section 1917.119 Labor... (CONTINUED) MARINE TERMINALS Terminal Facilities § 1917.119 Portable ladders. (a) Scope and applicability. This section applies to all portable ladders, including job-made ladders for temporary use,...