Sample records for donor immunoassay cedia

  1. Optimization and validation of CEDIA drugs of abuse immunoassay tests in serum on Hitachi 912.

    PubMed

    Kirschbaum, Katrin M; Musshoff, Frank; Schmithausen, Ricarda; Stockhausen, Sarah; Madea, Burkhard

    2011-10-10

    Due to sensitive limits of detection of chromatographic methods and low limit values regarding the screening of drugs under the terms of impairment in safe driving (§ 24a StVG, Street Traffic Law in Germany), preliminary immunoassay (IA) tests should be able to detect also low concentrations of legal and illegal drugs in serum in forensic cases. False-negatives should be avoided, the rate of false-positive samples should be low due to cost and time. An optimization of IA cutoff values and a validation of the assay is required for each laboratory. In a retrospective study results for serum samples containing amphetamine, methylenedioxy derivatives, cannabinoids, benzodiazepines, cocaine (metabolites), methadone and opiates obtained with CEDIA drugs of abuse reagents on a Hitachi 912 autoanalyzer were compared with quantitative results of chromatographic methods (gas or liquid chromatography coupled with mass spectrometry (GC/MS or LC/MS)). Firstly sensitivity, specificity, positive and negative predictive values and overall misclassification rates were evaluated by contingency tables and compared to ROC-analyses and Youden-Indices. Secondly ideal cutoffs were statistically calculated on the basis of sensitivity and specificity as decisive statistical criteria with focus on a high sensitivity (low rates of false-negatives), i.e. using the Youden-Index. Immunoassay (IA) and confirmatory results were available for 3014 blood samples. Sensitivity was 90% or more for nearly all analytes: amphetamines (IA cutoff 9.5 ng/ml), methylenedioxy derivatives (IA cutoff 5.5 ng/ml), cannabinoids (IA cutoff 14.5 ng/ml), benzodiazepines (IA cutoff >0 ng/ml). Test of opiates showed a sensitivity of 86% for a IA cutoff value of >0 ng/ml. Values for specificity ranged between 33% (methadone, IA cutoff 10 ng/ml) and 90% (cocaine, IA cutoff 20 ng/ml). Lower cutoff values as recommended by ROC analyses were chosen for most tests to decrease the rate of false-negatives. Analyses enabled the definition of cutoff values with good values for sensitivity. Small rates of false-positives can be accepted in forensic cases. PMID:21775079

  2. Optimization and validation of CEDIA drugs of abuse immunoassay tests in serum on Hitachi 912

    Microsoft Academic Search

    Katrin M. Kirschbaum; Frank Musshoff; Ricarda Schmithausen; Sarah Stockhausen; Burkhard Madea

    2011-01-01

    Due to sensitive limits of detection of chromatographic methods and low limit values regarding the screening of drugs under the terms of impairment in safe driving (§ 24a StVG, Street Traffic Law in Germany), preliminary immunoassay (IA) tests should be able to detect also low concentrations of legal and illegal drugs in serum in forensic cases. False-negatives should be avoided,

  3. Immunoassay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immunoassays are analytical methods that employ antibodies or molecules derived from antibodies for the essential binding reactions. The choice of immunoassay system for food safety analysis depends on the analyte, the matrix, and the requirements of the analysis (speed, throughput, sensitivity, spe...

  4. Immunoassays

    NASA Astrophysics Data System (ADS)

    Hsieh, Y.-H. Peggy

    Immunochemistry is a relatively new science that has developed rapidly in the last few decades. One of the most useful analytical developments associated with this new science is immunoassay. Originally immunoassays were developed in medical settings to facilitate the study of immunology, particularly the antibody-antigen interaction. Immunoassays now are finding widespread applications outside the clinical field because they are appropriate for a wide range of analytes ranging from proteins to small organic molecules. In the food analysis area, immunoassays are widely used for chemical residue analysis, identification of bacteria and viruses, and detection of proteins in food and agricultural products. Protein detection is important for determination of allergens and meat species content, seafood species identification, and detection of genetically modified plant tissues. While immunoassays of all formats are too numerous to cover completely in this chapter, there are several procedures that have become standard for food analysis because of their specificity, sensitivity, and simplicity.

  5. Immunoassays

    Microsoft Academic Search

    Michael J. O'Sullivan

    Immunoassays are used in basic biological research to investigate the physiological and possible pathological role of a wide range of biologically active substances including cyclic nucleotides, prostaglandins, leukotrienes, growth factors and cytokines [1]. Such research often leads to the identification of new potential targets for therapeutic agents.The assays are also used in the pharmaceutical industry in many aspects of the

  6. Comparison of immunoassay screening tests and LC-MS-MS for urine detection of benzodiazepines and their metabolites: results of a national proficiency test.

    PubMed

    Bertol, Elisabetta; Vaiano, Fabio; Borsotti, Maurizio; Quercioli, Massimo; Mari, Francesco

    2013-01-01

    For most diverse purposes, different immunoassay (IA) screening methods are usually used to detect benzodiazepines and their metabolites in urine. In this study, we compared the main IAs used in forensic toxicology (Cloned Enzyme Donor Immunoassay, CEDIA®; Enzyme-Multiplied Immunoassay Technique, EMIT®; Fluorescent Polarization ImmunoAssay, FPIA®; Kinetic Interaction of Microparticles in Solution, KIMS® and Immunochromatographic Techniques, IMC) with liquid chromatography-tandem mass spectrometry (LC-MS-MS). Twelve urine specimens were analyzed by 178 laboratories in Italy that participated in a National Proficiency Test, providing both qualitative and semi-quantitative results. Each IA was evaluated by the parameters: true positive, true negative, false positive (FP), false negative (FN), sensitivity (SENS), specificity (SPEC), positive predictive value, negative predictive value (NPV) and accuracy. SPEC was affected by a high FP rate for all IAs. The lowest SENS and NPV were provided by FPIA due to a high number of FN cases. Comparing IA semi-quantitative data with LC-MS-MS results, an overestimation of benzodiazepine amount is noted. This paper draws attention to the problem of the careless use of IA tests for forensic purposes as they may provide FP and/or FN results that can lead to errors of great severity. PMID:23943436

  7. Alternative immunoassays

    SciTech Connect

    Collins, W.P.

    1985-01-01

    This book contains 13 chapters. Some of the chapter titles are: Uses of immunoassay; Particle immunoassays; Immunoradiometric assays; Enzyme immunoassays; and Current concepts and future developments.

  8. Cross-reactivity of the CEDIA buprenorphine assay with opiates: an Austrian phenomenon?

    PubMed

    Pavlic, M; Libiseller, K; Grubwieser, P; Rabl, W

    2005-11-01

    When testing the Microgenics CEDIA assay for immunological buprenorphine analysis, cross-reactivity between the buprenorphine reagents and opiates was observed at concentrations higher than 120 mg/l morphine, 320 mg/l methadone, 30 mg/l codeine, 60 mg/l dihydrocodeine and 520 mg/l morphine-3-glucuronide. The cross-reactivity with morphine has the greatest impact on routine screening as opiate maintenance therapy in Austria is also performed with slow-release oral morphine. The use of a second cutoff value of 30 mug/l for urine samples that are (immunologically) positive for opiates is therefore suggested, compared to the cutoff value of 5 microg/l proposed by the manufacturer. PMID:15834736

  9. Determining immunoassay cutoff value using Western blot results to predict hepatitis C infection in blood donors with low-titer anti-HCV reactivity.

    PubMed

    Kucukbayrak, Abdulkadir; Cakmak, Saadet; Hakyemez, Ismail Necati; Tas, Tekin; Akdeniz, Hayrettin

    2013-07-01

    Since the 1990s, blood donors have been scanned for anti-hepatitis C virus (anti-HCV) antibodies, which can be defined by enzyme immunoassay as a screening test. In this population, false-reactive ratios have been high. Recently, some authors have aimed to find a cutoff value for anti-HCV different from those established by test manufacturers to predict HCV infection. In this study, 321 patients, after two repeating tests, had reactive results in s/co <10 titers on anti-HCV test. The patients were 29.6 % (n?=?95) in women and 70.4 % (n?=?226) in men. The patients were classified into three groups by Western blot (WB) results (PS, positive; NG, negative; and ID, indeterminate). The average anti-HCV titer of the whole group was 2.61?±?1.96. Anti-HCV titers of subgroups were 2.43?±?1.95 in NG, 4.93?±?2.53 in PS, and 2.50?±?1.65 in ID (p?2.61 s/co, with 74.1 % sensitivity and 71.6 % specificity (area under the curve, 0.820; 95 % confidence interval, 0.753 to 0.887). We suggest that an effective cutoff value for anti-HCV other than that established by the manufacturer cannot be assigned to predict hepatitis C infection for blood donors in low-prevalence areas. PMID:23208738

  10. Multicentre evaluation of the Boehringer Mannheim Hitachi 911 system for homogeneous immunoassays.

    PubMed

    González Buitrago, J M; Ruiz, J; García Bastos, J L; Navajo, J A; Borque, L; Maside, C; Rodriguez, A; Balas, D; Palet, A

    1994-06-01

    A multicentre evaluation of the new analyser, Hitachi 911, is reported for three different classes of homogeneous immunoassays (latex assays, immunoprecipitation assays, and CEDIA assays). The evaluation protocol follows ECCLS, IFCC and NCCLS guidelines. Using patient samples and commercial controls, within run and between run coefficients of variation were less than 3% in most cases, but as high as 9.7% for some CEDIA and latex assays. All the assays were linear, either in the reference or the therapeutic range of the analytes. No interference by haemolysis, lipaemia or icterus was observed. The methods were compared with other commercial methods. Coefficients of correlation were higher than 0.94 for all the methods. However, there were differences of slope and intercept for rheumatoid factor, apolipoprotein A-I and apolipoprotein B. On the Hitachi 911, all of the eight methods give precise and accurate results, and compare well with other established methods on immunoassay dedicated analysers. The discrepancies observed could be ascribed to current problems of immunoassay standardization. PMID:7918850

  11. Immunoassay Animations

    NSDL National Science Digital Library

    Chung, Kyn Wai

    This site features animations showing the detailed steps involved in eight different immunoassay examples. The focus of the site is primarily on the biochemical aspects of the immunoassays, not on their analytical applications. The animations depict the following immunoassays: Dihydroxy Vitamin D, ACTH, Bone­specific Alkaline Phosphatase, Cortisol, Deoxypyridinoline, Osteocalcin, Prolactin and Thyroxine.

  12. Immunoassay Animations

    NSDL National Science Digital Library

    Chung, KynWai.

    1996-01-01

    The University of Glasgow Department of Pathological Biochemistry has recently made available five immunoassay animations that draw on the interactivity of the FutureSplash plug-in (discussed in the December 20, 1996 issue of the Scout Report). The animations are "a learning resource for students, to show the wide application of the use of antibodies in a clinical biochemistry laboratory," and are "graphical representations of the immunoassay methodology used by a number of commercial manufacturers." Each immunoassay is presented as a series of animations, allowing the user to navigate forward and back in time. A key is provided, and animations can be viewed step by step (with explanations) and then replayed as a single continuous animation without explanations or navigation. Immunoassay Animations is a powerful visual teaching tool.

  13. Microfluidic Immunoassays

    Microsoft Academic Search

    Chun-Che Lin; Jung-Hao Wang; Hui-Wen Wu; Gwo-Bin Lee

    2010-01-01

    Immunoassays have long been widely used in a variety of applications, such as for medical diagnostics, pharmaceutical analysis, environmental, food safety testing, and for basic scientific investigations because of its simplicity, sensitivity, and specificity. Microfluidic systems, also well known as a “lab-on-a-chip” or a “micro-total-analysis-system” have attracted a lot of attention in the past two decades because of advantages associated

  14. Immunoassays in Biotechnology

    EPA Science Inventory

    Immunoassays have broad applications for a wide variety of important biological compounds and environmental contaminants. Immunoassays can detect the presence of an antigen in the human body, a pollutant in the environment, or a critical antibody in a patient?s serum to develop a...

  15. Determination of Ritalinic Acid in Autopsy Material Using SPE and

    Microsoft Academic Search

    Waler Martz; Niels Tobias; Bernd Mühlbauer

    A toddler who had lived with drug addict parents, was found dead. The autopsy could not confirm any unequivocal cause of death. Therefore, a toxicological screening was ordered by the prosecutor. The goal of our examination was to identify or exclude drugs potentially contribu- ting to the death of the child. This screening involved Cloned-Enzyme-Donor-Immunoassay (CEDIA) and Fluorescence-Polarization-Immunoassay (FPIA), a

  16. Microfluidic Chips for Immunoassays

    NASA Astrophysics Data System (ADS)

    Han, Kwi Nam; Li, Cheng Ai; Seong, Gi Hun

    2013-06-01

    The use of microfluidic chips for immunoassays has been extensively explored in recent years. The combination of immunoassays and microfluidics affords a promising platform for multiple, sensitive, and automatic point-of-care (POC) diagnostics. In this review, we focus on the description of recent achievements in microfluidic chips for immunoassays categorized by their detection method. Following a brief introduction to the basic principles of each detection method, we examine current microfluidic immunosensor detection systems in detail. We also highlight interesting strategies for sensitive immunosensing configurations, multiplexed analysis, and POC diagnostics in microfluidic immunosensors.

  17. Interferences in Immunoassay

    PubMed Central

    Tate, Jill; Ward, Greg

    2004-01-01

    Substances that alter the measurable concentration of the analyte or alter antibody binding can potentially result in immunoassay interference. Interfering, endogenous substances that are natural, polyreactive antibodies or autoantibodies (heterophiles), or human anti-animal antibodies together with other unsuspected binding proteins that are unique to the individual, can interfere with the reaction between analyte and reagent antibodies in immunoassay. Lipaemia, cross-reactivity, and exogenous interferences due to pre-analytical variation, matrix and equipment reaction also affect immunoassay. Interfering substances may lead to falsely elevated or falsely low analyte concentration in one or more assay systems depending on the site of the interference in the reaction and possibly result in discordant results for other analytes. The prevalence of interference is generally low in assays containing blocking agents that neutralise or inhibit the interference but is often higher in new, untested immunoassays. A wide range of analytes measured by immunoassay including hormones, tumour markers, drugs, cardiac troponin and microbial serology may be affected. Interference in immunoassay may lead to the misinterpretation of a patient's results by the laboratory and the wrong course of treatment being given by the physician. Laboratories should put processes in place to detect, test and report suspected interferences. It is equally important that physicians communicate any clinical suspicion of discordance between the clinical and the laboratory data to the laboratory. The detection of interference may require the use of an alternate assay or additional measurements, before and after treatment with additional blocking reagent, or following dilution of the sample in non-immune serum. It is imperative that laboratories inform physicians of the follow-up procedure and report on the presence of any interference. The establishment of on-going laboratory-physician contact is essential to the continuing awareness of wrong patient results due to interference. PMID:18458713

  18. Interferences in immunoassay.

    PubMed

    Tate, Jill; Ward, Greg

    2004-05-01

    Substances that alter the measurable concentration of the analyte or alter antibody binding can potentially result in immunoassay interference. Interfering, endogenous substances that are natural, polyreactive antibodies or autoantibodies (heterophiles), or human anti-animal antibodies together with other unsuspected binding proteins that are unique to the individual, can interfere with the reaction between analyte and reagent antibodies in immunoassay. Lipaemia, cross-reactivity, and exogenous interferences due to pre-analytical variation, matrix and equipment reaction also affect immunoassay. Interfering substances may lead to falsely elevated or falsely low analyte concentration in one or more assay systems depending on the site of the interference in the reaction and possibly result in discordant results for other analytes. The prevalence of interference is generally low in assays containing blocking agents that neutralise or inhibit the interference but is often higher in new, untested immunoassays. A wide range of analytes measured by immunoassay including hormones, tumour markers, drugs, cardiac troponin and microbial serology may be affected. Interference in immunoassay may lead to the misinterpretation of a patient's results by the laboratory and the wrong course of treatment being given by the physician. Laboratories should put processes in place to detect, test and report suspected interferences. It is equally important that physicians communicate any clinical suspicion of discordance between the clinical and the laboratory data to the laboratory. The detection of interference may require the use of an alternate assay or additional measurements, before and after treatment with additional blocking reagent, or following dilution of the sample in non-immune serum. It is imperative that laboratories inform physicians of the follow-up procedure and report on the presence of any interference. The establishment of on-going laboratory-physician contact is essential to the continuing awareness of wrong patient results due to interference. PMID:18458713

  19. Enzyme immunoassay for methamphetamine.

    PubMed

    Aoki, K; Kuroiwa, Y

    1983-01-01

    A competitive enzyme immunoassay for methamphetamine with alkaline phosphatase labeled methamphetamine, Sepharose-antibody and p-nitrophenylphosphate as substrate was developed. The anti-methamphetamine antisera produced in rabbits by immunization with N-(4-aminobutyl) methamphetamine-BSA conjugate were specific for methamphetamine and showed low cross-reactivities with p-OH methamphetamine and amphetamine (metabolites of methamphetamine). The range of methamphetamine measurable by the enzyme immunoassay was 1 to 300 ng/tube. According to the assay, methamphetamine could be detected from urine and extract of hair. PMID:6343585

  20. Mass spectrometric immunoassay

    DOEpatents

    Nelson, Randall W (Phoenix, AZ); Williams, Peter (Phoenix, AZ); Krone, Jennifer Reeve (Granbury, TX)

    2007-12-04

    Rapid mass spectrometric immunoassay methods for detecting and/or quantifying antibody and antigen analytes utilizing affinity capture to isolate the analytes and internal reference species (for quantification) followed by mass spectrometric analysis of the isolated analyte/internal reference species. Quantification is obtained by normalizing and calibrating obtained mass spectrum against the mass spectrum obtained for an antibody/antigen of known concentration.

  1. Mass spectrometric immunoassay

    DOEpatents

    Nelson, Randall W.; Williams, Peter; Krone, Jennifer Reeve

    2005-12-13

    Rapid mass spectrometric immunoassay methods for detecting and/or quantifying antibody and antigen analytes utilizing affinity capture to isolate the analytes and internal reference species (for quantification) followed by mass spectrometric analysis of the isolated analyte/internal reference species. Quantification is obtained by normalizing and calibrating obtained mass spectrum against the mass spectrum obtained for an antibody/antigen of known concentration.

  2. Mass spectrometric immunoassay

    DOEpatents

    Nelson, Randall W; Williams, Peter; Krone, Jennifer Reeve

    2013-07-16

    Rapid mass spectrometric immunoassay methods for detecting and/or quantifying antibody and antigen analytes utilizing affinity capture to isolate the analytes and internal reference species (for quantification) followed by mass spectrometric analysis of the isolated analyte/internal reference species. Quantification is obtained by normalizing and calibrating obtained mass spectrum against the mass spectrum obtained for an antibody/antigen of known concentration.

  3. Multiprotein Immunoassay Arrays Fabricated by Microcontact Printing

    E-print Network

    Reifenberger, Ronald G.

    Multiprotein Immunoassay Arrays Fabricated by Microcontact Printing H. D. Inerowicz,,§ S. Howell, F. After fabrication, immunoassays were successfully performed using the patterned protein microarrays. The developed immunoassays were characterized by fluorescence microscopy and scanning probe microscopy

  4. Immunoassay in healthcare testing applications.

    PubMed

    DePriest, Anne Z; Black, David L; Robert, Timothy A

    2015-01-01

    Immunoassay is used extensively for drug testing in pain management. Drug testing for the purpose of compliance monitoring is fundamentally different from forensic applications, which may rely on immunoassay screening to rapidly identify "negative" samples. In clinical settings, focus is shifted from identification of select drugs of abuse with low positivity rates to detection of a wide variety of licit and illicit compounds with expected high positivity rates. The primary drug classes of interest in this population, opioids and benzodiazepines, require special testing considerations when immunoassay is used. This review highlights the performance characteristics of immunoassay, with special emphasis on prescription drug classes and testing at the point-of-care. PMID:25750161

  5. Immunoassays for pesticide monitoring

    NASA Astrophysics Data System (ADS)

    Wengatz, Ingrid; Szurdoki, Ferenc; Swamy, Anand R.; Evans, Lawrence, III; Patonay, Gabor; Stimmann, Eric; Delwiche, Michael; Stoutamire, Donald; Gee, Shirley J.; Hammock, Bruce D.

    1995-05-01

    This study compares two formats of rapid assays for the detection of pesticides (bromacil and pyrethroid based metabolites): enzyme linked immunosorbent assay (ELISA) and immunoassay with near-infrared (NIR) fluorescence detection. NIR dye immunoassay (NIRDIA) measurements were carried out by using two different instruments, both having a silicon photodiode as the detector and a laser diode for excitation. ELISA and NIRDIA were performed in a tracer format, where the specific antibody is bound to the surface of a microtiter plate well and the tracer with enzyme or fluorescent dye label competes with the analyte for the antibody binding site. It was demonstrated that the NIRDIA is at least as sensitive as the ELISA. Both assays detect pesticides in the (mu) g/L (ppb) range. Hapten- macromolecule-NIR dye-conjugates have been synthesized with various biopolymers (e.g., proteins) as carriers. The use of carrier macromolecules enables convenient purification of the cyanine dye derivatives. The mild conjugation method of the dye is based on isothiocyanate chemistry.

  6. Morphological resonances for multicomponent immunoassays

    SciTech Connect

    Whitten, W.B.; Shapiro, M.J.; Ramsey, J.M. [Chemical and Analytical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6142 (United States); Bronk, B.V. [United States Army Edgewood Research, Development and Engineering Center, Edgewood, Maryland 21010 (United States)

    1995-06-20

    An immunoassay technique capable of detecting and identifying a number of species of microorganisms in a single analysis is described. The method uses optical-resonance size discrimination of microspheres to identify antibodies to which stained microorganisms are bound.

  7. Competitive Quenching Fluorescence Immunoassay for Chlorophenols Based on

    E-print Network

    Hammock, Bruce D.

    Competitive Quenching Fluorescence Immunoassay for Chlorophenols Based on Laser microdroplets by a homogeneous quenching fluorescence immunoassay (QFIA). The competitive immunoassay oc- curs the opportunity for miniaturization and high- throughput screening. Fluorescence immunoassays (fluoroimmu

  8. Donor Tag Game

    MedlinePLUS

    ... Games > Donor Tag Game Printable Version Donor Tag Game This feature requires version 6 or later of ... Blood Donor Community Donor Stories Recipient Stories SleevesUp Games Facebook Fanbox Avatars and Badges Banners eCards Enter ...

  9. Immunoassays DOI: 10.1002/anie.200502862

    E-print Network

    Mayer, Michael

    Immunoassays DOI: 10.1002/anie.200502862 Label-Free Affinity Assays by Rapid Detection of Immune-based sensing of specific complexes may enable portable or high-throughput immunoassays for diagnostics

  10. Field Analytic Technologies: Immunoassay and Enzymatic Assays

    NSDL National Science Digital Library

    This site features a discussion of immunoassays in the context of testing for environmental contaminants, including a fairly detailed explanation of how immunoassays are conducted and advantages and limitations in the analysis of environmental problems. There is also a discussion of analytical concerns - interferences, limits of detection, accuracy and precision, calibrating immunoassays, etc.

  11. Mass spectrometric immunoassay.

    PubMed

    Nelson, R W; Krone, J R; Bieber, A L; Williams, P

    1995-04-01

    A new, general method of immunoassay is demonstrated. The approach is based on the microscale immunoaffinity capture of target antigens followed by mass-specific identification and quantitation using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Immunoaffinity capture of antigens effectively overcomes signal suppression effects typically encountered during traditional matrix-assisted laser desorption/ionization analysis of complex biological mixtures while simultaneously concentrating the analyte into a small volume. Mass spectrometric detection of antigens is unambiguous, as antigen signals are observed at characteristic mass-to-charge values in the mass spectrum, offering a high level of immunity to artifacts due to nonbiospecific retention of mixture components. However, the most important aspect of such mass-specific detection is the ability to use a single assay to screen biological systems for the presence of multiple, mass-resolved antigens. Analyte quantitation is possible by using a single antibody to capture both the antigen and an antigen variant which has been chemically modified to have a different mass. With proper calibration, the relative signal intensities of the two species in the mass spectrum can be used to determine the antigen concentration. Sample incubation and processing methods were such that a typical analysis could be performed in less than 1 h while subnanomolar sensitivities were maintained. The technique has been used for the rapid, selective, and quantitative screening of human blood for the presence of myotoxin a, and Mojave toxin form the venoms of the prairie rattlesnakes, Crotalus viridis viridis, and and the Mojave rattlesnake, Crotalus scutulatus scutulatus. PMID:15134097

  12. Bioelectrochemical Immunoassay of Polychlorinated Biphenyl

    SciTech Connect

    Lin, Ying-Ying; Liu, Guodong; Wai, Chien M.; Lin, Yuehe

    2008-04-01

    A simple, rapid, and highly sensitive bioelectrochemical immunoassay method based on magnetic beads (MBs) and disposable screen-printed electrodes (SPE) has been developed to detect polychlorinated biphenyls (PCBs). The principle of this bioassay is based on a direct competitive enzyme-linked immunosorbent assay using PCB-antibody-coated MBs and horseradish peroxidase (HRP)-labeled PCB (HRP-PCB). A magnetic process platform was used to mix and shake the samples during the immunoreactions and to separate free and unbound reagents after the liquid-phase competitive immunoreactions among PCB-antibody-coated MBs, PCB analyte, and HRP-PCB. After a complete immunoassay, the HRP tracers attached to MBs were transferred to a substrate solution containing o-aminophenol and hydrogen peroxide for electrochemical detection. The different parameters, including the amount of HRP-PCB conjugates, immunoreaction time, and the concentration of substrate that governs the analytical performance of the immunoassay have been studied in detail and optimized. The detection limit of 5 pg mL-1 was obtained under optimum experimental conditions. The performance of this bioelectrochemical immunoassay was successfully evaluated with untreated river water spiked with PCBs, and the results were validated by commercial PCB enzyme-linked immunosorbent assay kit, indicating that this convenient and sensitive technique offers great promise for decentralized environmental application and trace PCBs monitoring.

  13. Living Donor Liver Transplantation

    MedlinePLUS

    ... the donor's blood type matches the recipient’s blood type. Next, the transplant team will measure liver and kidney function as well as red cell, white cell, and platelet counts. The donor is also tested for viruses ... the donor’s and recipient’s blood types are compatible, the donor will get a physical ...

  14. Homogeneous fluorescence polarization immunoassay for eicosanoids

    Microsoft Academic Search

    M. Matt; A. Nicolas; M. Donner; J. F. Stoltz

    1992-01-01

    Homogeneous fluorescence polarization immunoassay (FPIA) was applied to the development of an immunoassay of prostaglandin E1 (PGE1) selected as a model of eicosanoids. PGE1 was derivatized with fluoresceinthiocarbamyl ethylenediamine and purified by thin layer chromatography (TLC). The purity was checked by high performance liquid chromatography (HPLC). A radioimmunoassay was realized to ensure of the immunocompetition of the tracer. After the

  15. Fluorescence Polarization Immunoassay of Mycotoxins: A Review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immunoassays are routinely used in the screening of commodities and foods for fungal toxins (mycotoxins). Demands to increase speed and lower costs have lead to continued improvements in such assays. Because many reported mycotoxins are low molecular weight (below 1 Kdal), immunoassays for their d...

  16. Our Future Donors

    ERIC Educational Resources Information Center

    Miller, Richard E.

    2004-01-01

    The rhetorical advantages and dangers involved in casting the students as "future donors" are explained. The way in which the institutions have to change for casting its students as future donors is described.

  17. Becoming a Donor

    MedlinePLUS

    ... by Organ and Gender. > U.S. Waiting List Candidate Data HOW TO BECOME A DONOR The most important thing to do is to sign up as an organ and tissue donor in your state's donor registry. To cover all bases, it's also helpful to: Designate your decision on ...

  18. Novel immunoassay formats for integrated microfluidic circuits: diffusion immunoassays (DIA)

    NASA Astrophysics Data System (ADS)

    Weigl, Bernhard H.; Hatch, Anson; Kamholz, Andrew E.; Yager, Paul

    2000-03-01

    Novel designs of integrated fluidic microchips allow separations, chemical reactions, and calibration-free analytical measurements to be performed directly in very small quantities of complex samples such as whole blood and contaminated environmental samples. This technology lends itself to applications such as clinical diagnostics, including tumor marker screening, and environmental sensing in remote locations. Lab-on-a-Chip based systems offer many *advantages over traditional analytical devices: They consume extremely low volumes of both samples and reagents. Each chip is inexpensive and small. The sampling-to-result time is extremely short. They perform all analytical functions, including sampling, sample pretreatment, separation, dilution, and mixing steps, chemical reactions, and detection in an integrated microfluidic circuit. Lab-on-a-Chip systems enable the design of small, portable, rugged, low-cost, easy to use, yet extremely versatile and capable diagnostic instruments. In addition, fluids flowing in microchannels exhibit unique characteristics ('microfluidics'), which allow the design of analytical devices and assay formats that would not function on a macroscale. Existing Lab-on-a-chip technologies work very well for highly predictable and homogeneous samples common in genetic testing and drug discovery processes. One of the biggest challenges for current Labs-on-a-chip, however, is to perform analysis in the presence of the complexity and heterogeneity of actual samples such as whole blood or contaminated environmental samples. Micronics has developed a variety of Lab-on-a-Chip assays that can overcome those shortcomings. We will now present various types of novel Lab- on-a-Chip-based immunoassays, including the so-called Diffusion Immunoassays (DIA) that are based on the competitive laminar diffusion of analyte molecules and tracer molecules into a region of the chip containing antibodies that target the analyte molecules. Advantages of this technique are a reduction in reagents, higher sensitivity, minimal preparation of complex samples such as blood, real-time calibration, and extremely rapid analysis.

  19. EnzymeImmunoassay, KineticMicroparticle Immunoassay,Radioimmunoassay, and Fluorescence PolarizationImmunoassay Comparedfor Drugs-of-Abuse Screening

    Microsoft Academic Search

    David A. Armbruster; Robert H. Schwarzhoff; Edward C. Hubster; Monica K. Liserio

    The newestformulation ofthe Syva EMIT assayfor drugs of abuse, EMIT II, and a new immunoassay, OnUne (Roche), utilizing the kinetic interaction of microparticles in solution(KIMS)methodology, RIA tests,and TDx fluo- rescence polarization immunoassay (FPIA) procedures were compared for marijuana,cocaine,opiates,and bar- biturates.BothEMIT II and OnLineimmunoassays were performedwitha Hitachi717 analyzer.Calibration curves, the degree of separationbetween negativeand cutoff calibrators, precision,likelihood ofcarryoverfrompositive to negativesamples,andoverallease andspeedofanal-

  20. Selecting unrelated donors

    PubMed Central

    2015-01-01

    TEASER You are selecting an unrelated donor for a 40 year old man with AML in CR2. Which donor would you select? FULL CASE You are selecting an unrelated donor for a 40 year old man with AML in second complete remission with high-risk cytogenetics. He is CMV seronegative with blood type A?. He is an only child. The search coordinators have identified the following options: OptionAge/sexHLA matching (9/10 matched donors)CMV statusBlood typeYour ResponseDonor 150 FSingle allele mismatch at HLA-ACMV ?A+24%Donor 230 MSingle allele mismatch at HLA-CCMV +O+22%Donor 330 MSingle antigen mismatch at HLA-DQCMV +A+54% PMID:19203734

  1. Colorimetric Immunoassay for Detection of Tumor Markers

    PubMed Central

    Yin, Yongmei; Cao, Ya; Xu, Yuanyuan; Li, Genxi

    2010-01-01

    Tumor markers are substances, usually proteins, produced by the body in response to cancer growth, or by the cancer tissue itself. They can be detected in blood, urine, or tissue samples, and the discovery and detection of tumor markers may provide earlier diagnosis of cancer and improved therapeutic intervention. Colorimetric immunoassays for tumor marker detection have attracted considerable attention, due to their simplicity and high efficiency. The traditionally used colorimetric immunoassays for the detection of tumor markers are based on enzyme-linked immunosorbent assays, and the great achievement of nanotechnology has further opened opportunities for the development of such kind of immunoassays. This paper will summarize recent advances in the field of colorimetric immunoassays for detecting tumor markers, which is aimed to provide an overview in this field, as well as experimental guidance for the learner. PMID:21614193

  2. An immunoassay for human transferrin.

    PubMed

    el Guindi, M; Skikne, B S; Covell, A M; Cook, J D

    1988-01-01

    The laboratory measurement of serum transferrin is a valuable adjunct in the assessment of both iron and protein nutritional status. Conventional assays based on the Fe-binding properties of this protein are tedious to perform, susceptible to Fe contamination, and require volumes of serum that can only be obtained by venous sampling. We describe in this report a two-site enzyme immunoassay (EIA) developed with the use of monoclonal antibodies. Ten microliters serum is diluted 1:20,000 before assay, reflecting a high degree of sensitivity. The variability of this EIA is comparable to conventional colorimetric assays for total iron-binding capacity (TIBC), and excellent correspondence was observed between these methods over a range in TIBC of 150-500 micrograms/dL (27-90 mumol/L). No consistent difference was observed with the EIA when performed on venous and capillary specimens obtained simultaneously. This method will facilitate the evaluation of Fe and protein status in nutritional surveys. PMID:3276135

  3. Rich Donors, Poor Countries

    ERIC Educational Resources Information Center

    Thomas, M. A.

    2012-01-01

    The shifting ideological winds of foreign aid donors have driven their policy towards governments in poor countries. Donors supported state-led development policies in poor countries from the 1940s to the 1970s; market and private-sector driven reforms during the 1980s and 1990s; and returned their attention to the state with an emphasis on…

  4. Living donor kidney exchange.

    PubMed

    Gentry, Sommer; Segev, Dorry L

    2011-01-01

    Living donor kidney exchange, also referred to as kidney paired donation (KPD), is a relatively new transplant modality that is growing by leaps and bounds in the U.S. From its first realization as an exchange of kidneys between two incompatible donor/recipient pairs, KPD has expanded to include compatible pairs, nondirected donors, three-way and larger exchanges, and living/deceased donor exchanges. Innovations both clinical (transporting organs instead of donors, and improved HLA screening) and mathematical (simulation to test policies, optimization to find better and more matches) have made this modality even more useful and accessible. There are several independent multi-center paired donation registries and many more single-center registries operating in the U.S., but incompatible pairs are most likely to match when they participate in the largest possible paired exchange pool; a single, unified KPD program in the United States would likely best serve patients in search of matches. PMID:22755420

  5. Electrothermal stirring for heterogeneous immunoassays Marin Sigurdson,a

    E-print Network

    Meinhart, Carl

    Electrothermal stirring for heterogeneous immunoassays Marin Sigurdson,a Dazhi Wangb and Carl D-sensors, for example, immunoassays, in which a ligand immobilized on a microchannel wall specifically binds analyte of these heterogeneous immunoassays may be improved by using AC electrokinetically-driven microscale fluid motion

  6. Ultrashort Separation Length Homogeneous Electrophoretic Immunoassays Using On-Chip

    E-print Network

    Herr, Amy E.

    Ultrashort Separation Length Homogeneous Electrophoretic Immunoassays Using On-Chip Discontinuous-color homogeneous electrophoretic immunoassay for concur- rent quantitation of C reactive protein (CRP) and tumor for near-patient environments. Homogeneous electrophoretic immunoassays are well-suited for and often

  7. Ultra-sensitive immunoassay using VCSEL detection system

    E-print Network

    Cunningham, Brian

    Ultra-sensitive immunoassay using VCSEL detection system C.F.R. Mateus, M.C.Y. Huang, C.J. Chang. In this Letter, we report the use of this system in immunoassay with a record high sensitivity to antigen be largely extended (32 nm) by using a MEMS tunable VCSEL [4]. Mouse IgG capture immunoassay: In this Letter

  8. PROBLEM 6: MASS TRANSPORT AND SURFACE REACTION OF IMMUNOASSAY

    E-print Network

    Kalisch, Henrik

    PROBLEM 6: MASS TRANSPORT AND SURFACE REACTION OF IMMUNOASSAY Jim Buchanan, Henrik Kalisch applications, the solid phase surface reactions and immunoassay technologies are widely used to determine of the Y. Antigen attached with a label is used in a variety of immunoassay techniques. The labeled antigen

  9. Application of Photonic Crystal Enhanced Fluorescence to a Cytokine Immunoassay

    E-print Network

    Cunningham, Brian

    Application of Photonic Crystal Enhanced Fluorescence to a Cytokine Immunoassay Patrick C. Mathias on the glass slidesa decrease from 18 to 6 pg/mL. The increased performance of the immunoassay allows for more detection has been an adaptation of the DNA microarray format to immunoassays. Fluorescence-based protein

  10. Marginal kidney donor

    PubMed Central

    Gopalakrishnan, Ganesh; Gourabathini, Siva Prasad

    2007-01-01

    Renal transplantation is the treatment of choice for a medically eligible patient with end stage renal disease. The number of renal transplants has increased rapidly over the last two decades. However, the demand for organs has increased even more. This disparity between the availability of organs and waitlisted patients for transplants has forced many transplant centers across the world to use marginal kidneys and donors. We performed a Medline search to establish the current status of marginal kidney donors in the world. Transplant programs using marginal deceased renal grafts is well established. The focus is now on efforts to improve their results. Utilization of non-heart-beating donors is still in a plateau phase and comprises a minor percentage of deceased donations. The main concern is primary non-function of the renal graft apart from legal and ethical issues. Transplants with living donors outnumbered cadaveric transplants at many centers in the last decade. There has been an increased use of marginal living kidney donors with some acceptable medical risks. Our primary concern is the safety of the living donor. There is not enough scientific data available to quantify the risks involved for such donation. The definition of marginal living donor is still not clear and there are no uniform recommendations. The decision must be tailored to each donor who in turn should be actively involved at all levels of the decision-making process. In the current circumstances, our responsibility is very crucial in making decisions for either accepting or rejecting a marginal living donor. PMID:19718332

  11. Hepatitis C antibody prevalence in blood donors in different governorates in Egypt

    Microsoft Academic Search

    Ray R. Arthur; Nassef Farahat Hassan; Mahasan Yousef Abdallah; Mohamed Said El-Sharkawy; Magdy Darwish Saad; Barbara G. Hackbart; Imam Zaghloul Imam

    1997-01-01

    Markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections were sought in serum samples from 2644 blood donors in 24 of Egypt's 26 governorates. Of the 2644 samples, 656 (24·8%) were shown to contain anti-HCV immunoglobulin G antibody by Abbott second generation enzyme immunoassays (EIA). Of 85 EIA-positive samples tested by recombinant immunoblot assay, 72 (85%) were

  12. Living-donor liver transplantation: evaluation of donor and recipient

    Microsoft Academic Search

    Peter Sauer; Peter Schemmer; Waldemar Uhl; Jens Encke

    2004-01-01

    Living-donor liver transplantation (LDLT) in adults has been expanded after becoming the standard for children in many transplant centres. Advantages of LDLT include thorough donor screening, optimization of timing for transplantation and minimal cold ischaemia time. However, the risk of donor morbidity and mortality must be considered. The preoperative evaluation of the donor typically is performed in consecutive stages. Specific

  13. Fluorescence Polarization Immunoassay for Insulin Preparations

    Microsoft Academic Search

    Y. Yamaguchi; C. Hayashi; K. Miyai

    1982-01-01

    A fluorescence polarization immunoassay for insulin preparations such as pharmaceutical preparation and solutions after chromatography is described. The assay is rapid, without separation of antibody-bound and free ligands.The minimal amount of insulin detected was 0.6 mU\\/ tube and the measurable range was from 40 to 600 mU\\/ml of solution.

  14. Analysis of Sulfamethazine by Fluorescence Polarization Immunoassay

    Microsoft Academic Search

    Zhan-Hui Wang; Su-Xia Zhang; Jian-Zhong Shen; A. Eremin Sergei

    2007-01-01

    A fluorescence polarization immunoassay (FPIA) was developed based on a polyclonal antibody for the determination and the qualitative screening analysis of sulfamethazine (SMZ). To optimize the FPIA procedures, three fluorescein-labeled SMZ and sulfamerazine (SMR) were synthesized, and the influence of their structures on the characteristics of FPIA was studied. The optimized FPIA for SMZ had a dynamic range from 5

  15. Monitoring human exposure to pesticides using immunoassay

    E-print Network

    Hammock, Bruce D.

    Monitoring human exposure to pesticides using immunoassay Marja E. Koivunen1,2 , Shirley J. Gee1, specific and sensitive tools for human exposure studies involving numerous samples in complex matrices (4 compound requires extensive knowledge about its biotransformation and metabolism in humans. Studies

  16. IMMUNOASSAY FOR P-NITROPHENOL IN URINE

    EPA Science Inventory

    Urinary excretion of nitrophenol metabolites is an important index of human exposure to organophosphate pesticides. In particular, p-nitrophenol, a major urinary metabolite of parathion, can be used as a biomarker of human exposure. Immunoassay methods have been recently describe...

  17. The right environment for the immunoassay

    SciTech Connect

    Emon, J.M. Van; Gerlach, C.L.

    1995-11-01

    For the US Environmental Protection Agency (EPA), the first in-house research effort began in 1987, when results of an early immunoassay field study verified the technology`s potential for environmental applications. Looking at the fundamental features of immunochemical reactions from the clinical laboratories, analytical chemists realized the potential value of these methods for hazardous waste site characterization and pesticide monitoring. Immunoassays rely on the interaction between an antibody and a target analyte. For environmental purposes, enzyme immunoassays are generally used. After the target analyte binds to the antibody, an enzymatic reaction yields a colorimetric change. This change, read visually or by a spectrophotometer, indicates the concentration of the target analyte. Promising results with assays for compounds (such as paraquat and pentachlorophenol) and compound groups (such as total petroleum hydrocarbons and polychlorinated biphenyls) spurred interest among various entrepreneurs. The first target market for immunoassays was environmental engineers and field crews who needed quick answers on-site to determine the direction of further remediation efforts.

  18. Toxocariasis: serological diagnosis by enzyme immunoassay

    Microsoft Academic Search

    D H de Savigny; A Voller; A W Woodruff

    1979-01-01

    An enzyme-immunoassay was developed to measure the concentration of serum antibody specific for the secretory antigens released by migrating toxocaral larvae. This technique was evaluated by testing sera from healthy UK adults, and from patients with and without toxocariasis. In 922 healthy adults, 2.6% were found to have elevated specific antibody levels. Elevated values were observed twice as frequently in

  19. Independent donor ethical assessment: aiming to standardize donor advocacy.

    PubMed

    Choudhury, Devasmita; Jotterand, Fabrice; Casenave, Gerald; Smith-Morris, Carolyn

    2014-06-01

    Living organ donation has become more common across the world. To ensure an informed consent process, given the complex issues involved with organ donation, independent donor advocacy is required. The choice of how donor advocacy is administered is left up to each transplant center. This article presents the experience and process of donor advocacy at University of Texas Southwestern Medical Center administered by a multidisciplinary team consisting of physicians, surgeons, psychologists, medical ethicists and anthropologists, lawyers, a chaplain, a living kidney donor, and a kidney transplant recipient. To ensure that advocacy remains fair and consistent for all donors being considered, the donor advocacy team at University of Texas Southwestern Medical Center developed the Independent Donor Ethical Assessment, a tool that may be useful to others in rendering donor advocacy. In addition, the tool may be modified as circumstances arise to improve donor advocacy and maintain uniformity in decision making. PMID:24919733

  20. Laboratory diagnosis of syphilis with automated immunoassays.

    PubMed

    Marangoni, Antonella; Moroni, Alessandra; Accardo, Silvia; Cevenini, Roberto

    2009-01-01

    The serological detection of specific antibodies to Treponema pallidum is of particular importance in the diagnosis of syphilis. The purpose of this study was to evaluate diagnostic performances of automated immunoassays in comparison with T. pallidum hemagglutination test (TPHA) and Western Blot (WB). The retrospective study was performed with different panels of sera: 244 clinical and serological characterized syphilitic sera and 203 potentially interfering samples. All the sera were tested by Enzygnost Syphilis, ARCHITECT Syphilis TP, TPHA, and homemade WB. The diagnostic performances of the two assays were very similar: both Enzygnost Syphilis and ARCHITECT Syphilis TP performed with a sensitivity of 99.2%, whereas the specificity was 98.5 and 98.4%, respectively. Considering the suitability for automation, both immunoassays may represent a good choice as a screening test. However, the use of a confirmatory test, such as TPHA or WB, remains a must in order to avoid false-positive results. PMID:19140205

  1. Enzyme immunoassay system for panel testing.

    PubMed

    Donohue, J; Bailey, M; Gray, R; Holen, J; Huang, T M; Keevan, J; Mattimiro, C; Putterman, C; Stalder, A; Defreese, J

    1989-09-01

    An immunoassay system based on enzyme immunoassay technology has been developed for quantitative panel testing. The system includes test card disposables, reagents, and an instrument. Patients' samples are processed semiautomatically in the instrument with minimum user intervention. The test card has multiple test areas at individual locations on a membrane solid phase so that simultaneous determinations from a single specimen are possible. Each panel also includes positive and negative reagent procedural controls. Factory-determined calibration curves for each analyte are provided in barcode form with each test kit. The reagents include a specimen dilution buffer, enzyme conjugate, and precipitogenic substrate. Up to 10 test cards at a time can be processed in random-access and continuous-access modes, with automated agitation of sample and reagents over the solid phase, temperature-controlled incubation, and membrane washing and reading, data reduction, and printout of results. The optical reader measures diffuse reflectance and features source intensity and wavelength compensation. PMID:2673584

  2. Immunoassay for Simazine and Atrazine with Low Cross-Reactivity for Propazine

    E-print Network

    Hammock, Bruce D.

    Immunoassay for Simazine and Atrazine with Low Cross-Reactivity for Propazine Monika Wortberg: Immunoassay; enzyme-linked immunosorbent assay (ELISA); simazine; atrazine; propazine; triazine herbicide pesticide contami- nation, several immunoassays for atrazine have been developed as screening tools

  3. Homogeneous Immunoassays: Historical Perspective and Future Promise

    NASA Astrophysics Data System (ADS)

    Ullman, Edwin F.

    1999-06-01

    The founding and growth of Syva Company is examined in the context of its leadership role in the development of homogeneous immunoassays. The simple mix and read protocols of these methods offer advantages in routine analytical and clinical applications. Early homogeneous methods were based on insensitive detection of immunoprecipitation during antigen/antibody binding. The advent of reporter groups in biology provided a means of quantitating immunochemical binding by labeling antibody or antigen and physically separating label incorporated into immune complexes from free label. Although high sensitivity was achieved, quantitative separations were experimentally demanding. Only when it became apparent that reporter groups could provide information, not only about the location of a molecule but also about its microscopic environment, was it possible to design practical non-separation methods. The evolution of early homogenous immunoassays was driven largely by the development of improved detection strategies. The first commercial spin immunoassays, developed by Syva for drug abuse testing during the Vietnam war, were followed by increasingly powerful methods such as immunochemical modulation of enzyme activity, fluorescence, and photo-induced chemiluminescence. Homogeneous methods that quantify analytes at femtomolar concentrations within a few minutes now offer important new opportunities in clinical diagnostics, nucleic acid detection and drug discovery.

  4. Immunoassay as a screening tool for industrial toxicants

    SciTech Connect

    Pierce, T.

    1986-08-01

    Immunoassay techniques may represent useful screening tools to assist analysts interested in the presence and amounts of organic toxicants in biological fluids. The widespread application of immunoassay methods in medicinal and forensic (drugs of abuse) chemistry has resulted in such screening methodologies. Four methodologies of potential benefit are considered: the free radical assay technique, the enzyme-mediated immunoassay technique, radioimmunoassay, and hemagglutination. Each of these immunoassays is based on the competitive displacement of the labeled drug (or toxicant) from the antibody complex by the unlabeled drug-toxicant in the sample.

  5. Hapten Synthesis and Antibody Development for Polychlorinated Dibenzo-p-dioxin Immunoassays

    E-print Network

    Hammock, Bruce D.

    Hapten Synthesis and Antibody Development for Polychlorinated Dibenzo-p-dioxin Immunoassays James R. Keywords: TCDD; dioxin; immunoassay; polyclonal antibodies; hapten synthesis; polychlorinated hydrocarbons

  6. GTEx Donor Eligibility Criteria Form

    Cancer.gov

    GENERAL INSTRUCTIONS This guidance provides general instructions and guidance for completing the GTEx Donor Eligibility Criteria Form (PM-0003-F4) which is used to determine acceptability of a potential donor into the GTEx study.

  7. Laboratory and epidemiologic evaluation of an enzyme immunoassay for antibodies to HTLV-III

    SciTech Connect

    Ward, J.W.; Grindon, A.J.; Feorino, P.M.; Schable, C.; Parvin, M.; Allen, J.R.

    1986-07-18

    The enzyme immunoassays (EIAs) for antibody to human T-cell lymphotropic virus type III (HTLV-III) were rapidly adopted for screening donated blood and plasma. To evaluate the significance of a positive EIA reaction, test performance was examined in a blood bank screening program. Specimens were tested by EIA, Western blot assay, and HTLV-III/lymphadenopathy-associated virus (LAV) culture. The EIA was positive in 0.25% of 67 190 blood donations. Specimens were categorized and 57.3% had low (weak) reactivity, 12.7% had moderate reactivity, and 30.0% had high reactivity. Highly reactive specimens were strongly associated with a positive Western blot or culture (86.7%) in contrast to moderately and weekly reactive specimens (1.9%). Twenty-five of 29 donors interviewed with a highly reactive EIA had risk factors for HTLV-III/LAV infection. Risk factors were not identified for 74 of 75 interviewed donors with specimens of lower reactivity. The minimum calculated specificity was 99.82%. The use of the HTLV-III EIA has virtually eliminated the use of blood and plasma for HTLV-III/LAV infected donors.

  8. Novel One-step Immunoassays to Quantify ?-Synuclein

    PubMed Central

    Bidinosti, Michael; Shimshek, Derya R.; Mollenhauer, Brit; Marcellin, David; Schweizer, Tatjana; Lotz, Gregor P.; Schlossmacher, Michael G.; Weiss, Andreas

    2012-01-01

    Familial Parkinson disease (PD) can result from ?-synuclein gene multiplication, implicating the reduction of neuronal ?-synuclein as a therapeutic target. Moreover, ?-synuclein content in human cerebrospinal fluid (CSF) represents a PD biomarker candidate. However, capture-based assays for ?-synuclein quantification in CSF (such as by ELISA) have shown discrepancies and have limited suitability for high-throughput screening. Here, we describe two sensitive, in-solution, time-resolved Förster's resonance energy transfer (TR-FRET)-based immunoassays for total and oligomeric ?-synuclein quantification. CSF analysis showed strong concordance for total ?-synuclein content between two TR-FRET assays and, in agreement with a previously characterized 36 h protocol-based ELISA, demonstrated lower ?-synuclein levels in PD donors. Critically, the assay suitability for high-throughput screening of siRNA constructs and small molecules aimed at reducing endogenous ?-synuclein levels was established and validated. In a small-scale proof of concept compound screen using 384 well plates, signals ranged from <30 to >120% of the mean of vehicle-treated cells for molecules known to lower and increase cellular ?-synuclein, respectively. Furthermore, a reverse genetic screen of a kinase-directed siRNA library identified seven genes that modulated ?-synuclein protein levels (five whose knockdown increased and two that decreased cellular ?-synuclein protein). This provides critical new biological insight into cellular pathways regulating ?-synuclein steady-state expression that may help guide further drug discovery efforts. Moreover, we describe an inherent limitation in current ?-synuclein oligomer detection methodology, a finding that will direct improvement of future assay design. Our one-step TR-FRET-based platform for ?-synuclein quantification provides a novel platform with superior performance parameters for the rapid screening of large biomarker cohorts and of compound and genetic libraries, both of which are essential to the development of PD therapies. PMID:22843695

  9. Determination of the herbicide acetochlor by fluorescence polarization immunoassay

    Microsoft Academic Search

    M. A. Deryabina; Yu. N. Yakovleva; V. A. Popova; S. A. Eremin

    2005-01-01

    A fluorescence polarization immunoassay procedure was developed for determining the herbicide acetochlor from the group of chloroacetanilides. Conjugates of fluorescent labeled acetochlor derivatives (tracers) with glycylaminofluorescein and ethylenediaminofluorescein were synthesized. The effect of the tracer structure on the analytical characteristics of the determination and on antigen-antibody binding constants was studied. The developed immunoassay procedures are characterized by a detection limit

  10. Fluorescence Polarization Immunoassay: Detection of Antibody to Brucella abortus

    Microsoft Academic Search

    Klaus Nielsen; Min Lin; David Gall; Michael Jolley

    2000-01-01

    Fluorescence polarization immunoassay (FPA) is a homogeneous immunoassay useful for rapid and accurate detection of antibody or antigen. The principle of the assay is that a fluorescent dye (attached to an antigen or an antibody fragment) can be excited by plane-polarized light at the appropriate wavelength. As a rule, a small molecule rotates faster when in solution than a larger

  11. Immunoassay detection without washing by using AC magnetic susceptibility

    Microsoft Academic Search

    Ryuzo Kawabata; Takako Mizoguchi; Akira Tsukamoto; Tomoko Yoshimura; Akihiko Kandori; Keiji Enpuku

    2010-01-01

    Our aim in this study was to demonstrate a stable immunoassay using the decrease of AC magnetic susceptibility without washing to separate bound and unbound magnetic markers. To achieve low noise in the immunoassay system, we examined the arrangement of the MR sensors, the calibration of the distance between the MR sensor and the sample, and the magnetic noise generated

  12. Validation of immunoassays for bioanalysis: a pharmaceutical industry perspective

    Microsoft Academic Search

    J. W. A. Findlay; W. C. Smith; J. W. Lee; G. D. Nordblom; I. Das; B. S. DeSilva; M. N. Khan; R. R. Bowsher

    2000-01-01

    Immunoassays are bioanalytical methods in which quantitation of the analyte depends on the reaction of an antigen (analyte) and an antibody. Although applicable to the analysis of both low molecular weight xenobiotic and macromolecular drugs, these procedures currently find most consistent application in the pharmaceutical industry to the quantitation of protein molecules. Immunoassays are also frequently applied in such important

  13. Enzyme immunoassays with special reference to ELISA techniques

    Microsoft Academic Search

    A Voller; A Bartlett; D E Bidwell

    1978-01-01

    In this review outlines are given on various types of enzyme immunoassay. The applications to such enzyme immunoassays, especially ELISA, are dealth with in detail. It is concluded that these techniques have high sensitivity and will be suitable in due course as routine laboratory tests.

  14. Interpretation of total petroleum hydrocarbon results with immunoassay test kits

    SciTech Connect

    Jourdan, S.; Scutellaro, A.; Hayes, M.; Herzog, D.P. [Ohmicron Environmental Diagnostics, Newtown, PA (United States)

    1995-12-31

    Petroleum derived fuels are complex mixtures of organic compounds, predominantly hydrocarbons, with varying compositions depending on source of the crude oil and its refining process. Results from current analytical methods for petroleum hydrocarbons may be generically referred to as Total Petroleum Hydrocarbons or TPH. Various immunoassay kits for petroleum products are now commercially available. Questions often arise when individuals new to immunoassay technology begin application of kits to these complex mixtures. Many users wish to compare results from the immunoassay screening test to a TPH laboratory results. Studies were conducted to demonstrate the nature of the relationship of common TPH methods with immunoassay methods. The immunoassays studied were developed for determination of volatile aromatic mixtures and for determination of polynuclear aromatic hydrocarbons.

  15. Blood Donor Management in China

    PubMed Central

    Shi, Ling; Wang, Jingxing; Liu, Zhong; Stevens, Lori; Sadler, Andrew; Ness, Paul; Shan, Hua

    2014-01-01

    Summary Despite a steady increase in total blood collections and voluntary non-remunerated blood donors, China continues to have many challenges with its blood donation system. The country's donation rate remains low at 9%o, with over 60% of donors being first-time donors. Generally there is a lack of adequate public awareness about blood donation. The conservative donor selection criteria, the relatively long donation interval, and the small donation volume have further limited blood supply. To ensure a sufficient and safe blood supply that meets the increasing clinical need for blood products, there is an urgent need to strengthen the country's blood donor management. This comprehensive effort should include educating and motivating more individuals especially from the rural areas to be involved in blood donation, developing rational and evidence-based selection criteria for donor eligibility, designing a donor follow-up mechanism to encourage more future donations, assessing the current donor testing strategy, improving donor service and care, building regional and national shared donor deferral database, and enhancing the transparency of the blood donation system to gain more trust from the general public. The purpose of the review is to provide an overview of the key process of and challenges with the blood donor management system in China. PMID:25254023

  16. Fluorescent immunoassay visualization of sorbed pollutants

    SciTech Connect

    Moore, W.K.; Mossman, D.J. [Univ. of Missouri-Columbia, Kansas City, MO (United States). Dept. of Civil Engineering; Schwab, A.P. [Kansas State Univ., Manhattan, KS (United States). Dept. of Agronomy; Feldbush, T.L. [Northwestern Univ., Evanston, IL (United States)

    1994-12-31

    Current methods of detecting sorbed soil pollutants require that the contaminant be extracted from the soil. In an effort to make detection simpler and safer, standard fluorescent immunoassay techniques are being modified to allow fluorescent tags on the pollutant to be viewed and photographed with epifluorescent microscopy. Initial research focuses on detecting chlorinated benzenes on various soil types and developing a technique for tagging these pollutants with appropriate antibodies. This should lead to detection in actual soil cores and a better understanding of how contaminants progress through different soils.

  17. Gliadin Detection in Food by Immunoassay

    NASA Astrophysics Data System (ADS)

    Grant, Gordon; Sporns, Peter; Hsieh, Y.-H. Peggy

    Immunoassays are very sensitive and efficient tests that are commonly used to identify a specific protein. Examples of applications in the food industry include identification of proteins expressed in genetically modified foods, allergens, or proteins associated with a disease, including celiac disease. This genetic disease is associated with Europeans and affects about one in every 200 people in North America. These individuals react immunologically to wheat proteins, and consequently their own immune systems attack and damage their intestines. This disease can be managed if wheat proteins, specifically "gliadins," are avoided in foods.

  18. Quantum-dot-basedFörster resonance energy transfer immunoassay for sensitive clinical diagnostics of low-volume serum samples.

    PubMed

    Wegner, K David; Jin, Zongwen; Lindén, Stina; Jennings, Travis L; Hildebrandt, Niko

    2013-08-27

    A myriad of quantum dot (QD) biosensor examples have emerged from the literature over the past decade, but despite their photophysical advantages, QDs have yet to find acceptance as standard fluorescent reagents in clinical diagnostics. Lack of reproducible, stable, and robust immunoassays using easily prepared QD-antibody conjugates has historically plagued this field, preventing researchers from advancing the deeper issues concerning assay sensitivity and clinically relevant detection limits on low-volume serum samples. Here we demonstrate a ratiometric multiplexable FRET immunoassay using Tb donors and QD acceptors, which overcomes all the aforementioned limitations toward application in clinical diagnostics. We demonstrate the determination of prostate specific antigen (PSA) in 50 ?L serum samples with subnanomolar (1.6 ng/mL) detection limits using time-gated detection and two different QD colors. This concentration is well below the clinical cutoff value of PSA, which demonstrates the possibility of direct integration into real-life in vitro diagnostics. The application of IgG, F(ab')2, and F(ab) antibodies makes our homogeneous immunoassay highly flexible and ready-to-use for the sensitive and specific homogeneous detection of many different biomarkers. PMID:23909574

  19. Amphetamine Positive Urine Toxicology Screen Secondary to Atomoxetine

    PubMed Central

    Fenderson, Joshua L.; Stratton, Amy N.; Domingo, Jennifer S.; Matthews, Gerald O.; Tan, Christopher D.

    2013-01-01

    The aim of this paper is to report the first case of atomoxetine leading to false-positive urine drug screen. An otherwise healthy 27-year-old female with a history of attention deficit hyperactivity disorder (ADHD) treated with atomoxetine had an acute onset tonic-clonic seizure. On arrival to the hospital, a urine toxicological drug screen with immunochemical cloned enzyme donor immunoassay (CEDIA) was performed. Results were positive for amphetamines; however, the presence of these substances could not be confirmed with urine gas chromatography-mass spectrometry (GC-MS). She denied any illicit drug use, herbal medications, or supplements, and her other prescription medications have not been previously known to cause a false-positive result for amphetamines. While stimulant treatments for ADHD could certainly result in a positive result on urine screen for amphetamines, there have been no reports of false-positive results for amphetamines secondary to patients using atomoxetine. We implicate atomoxetine, and/or its metabolites, as a compound or compounds which may interfere with urine drug immunoassays leading to false-positive results for amphetamines CEDIA assays. PMID:23424703

  20. Application of Antibody and Fluorophore-Derivatized Liposomes to Heterogeneous Immunoassays for D-dimer

    E-print Network

    Kilpatrick, Peter K.

    Application of Antibody and Fluorophore-Derivatized Liposomes to Heterogeneous Immunoassays for D-type) immunoassay for the detection of thromboembolic disorders by assaying for d-dimer. D-dimer is the final. The immunoassay using liposomes was compared to a conventional immunoassay that uses a fluor-antibody conjugate

  1. Fluorimetric immunoassay for multianalysis of aflatoxins.

    PubMed

    Kanungo, Lizy; Bhand, Sunil

    2013-01-01

    A sensitive fluorimetric ELISA was developed for the analysis of aflatoxins. The assay was performed in a 384 microwell plate, wherein high specificity monoclonal antibody against AFM1 (mAb-AFM1) was used as capture antibody and FITC conjugated secondary antibody was used for detection and quantification of the analyte. The linear range of the immunoassay was found to be 6.25-50?pg/mL. AFM1 as low as 1?pg/mL was detected by this method with assay volume 40? ? L. The multi-analysis of different aflatoxins was also investigated in the microwell plate, based on the cross-reactivity (CR) approach. Real milk samples were tested along with certified reference material by standard addition method and recovery analysis was done. The mAb-AFM1 showed 23.2% CR with AFB1, 50% CR with respect to AFM2, and least CR towards AFG1 (<1%). Furthermore, mixture analysis of AFM2 and AFB1 was carried out at specific concentrations of AFM1. The advantages of this developed immunoassay are high sensitivity, high throughput, multianalyte detection, versatility, and ease of handling. PMID:24000318

  2. Outcomes of living donor liver transplantation using elderly donors

    PubMed Central

    Han, Jae Hyun; Na, Gun Hyung; Kim, Eun Young; Lee, Soo Ho; Hong, Tae Ho; Kim, Dong Goo

    2014-01-01

    Purpose Living donor liver transplantation (LDLT) using elderly donors is increasing in frequency in response to organ shortage. However, elderly donor graft has been reported to negatively affect graft patency and patient survival. Methods We retrospectively reviewed the medical records of 604 patients who underwent LDLT at Seoul St. Mary's Hospital, The Catholic University of Korea between May 1999 and September 2012. Elderly donors were defined as those ?55 years of age. Here, we evaluate the survival differences and causes of death of recipients of elderly donor grafts. Results The overall mortality rate of the recipients was significantly higher in the elderly donor group (group A) than in the younger donor group (group B: 46.2% vs. 18.1%, P = 0.004). The survival length of group A was significantly shorter than that of group B (31.2 ± 31.3 and 51.4 ± 40.8 months, P = 0.014). The significantly common causes of death in group A were biliary (41.7%) and arterial complication (16.7%), and it was higher than those in group B (P = 0.000 and P = 0.043, respectively). Conclusion LDLT using elderly donors could induce more serious complications and higher mortality rates than those at using younger donors. As such, careful donor selection is needed, especially with regard to assessing the condition of potential elderly donor livers. Furthermore, a large-volume and multicenter study of complications and outcomes of LDLT using elderly donor liver is required. PMID:24783177

  3. Environmental monitoring by immunoassay: Current and future trends

    SciTech Connect

    Stanker, L.H.; Watkins, B.E.; Vanderlaan, M.

    1990-10-31

    Immunoassays for low molecular weight molecules have become increasingly popular in part, this is a result of the simplicity and potentially low cost of immunoassays when compared with conventional analytical methods. Environmental application of immunoassays, however, poses new challenges. First, not only must the parent compound be detected but often one would also like to detect metabolites or environmentally weathered'' products. Monoclonal antibody technology offers the possibility of selecting antibodies that have specific binding characteristics, eg. those that bind to a family of similar compounds or to broad classes of chemicals. Next, a simple rapid sample preparation method must be available. Unlike clinical assays that run in serum or other biological fluids (ideal matrixes for antibodies), environmental sample consist of soils, sediments, chemical sludges, water and air samples. Thus, in all cases, with the possible exception of water samples, the analyte of interest must be extracted and presented to the antibody in an appropriate buffer system. Once these criteria are met, immunoassays present an attractive alternative for conventional analytical methods. The most direct application of immunoassays will undoubtedly as as screening assays, with positives being confirmed by gas liquid chromatography/mass spectrometry (GC/MS). However, coupling immunoassay with other analytical methods, such as with high-pressure liquid chromatography (HPLC) converts a single residue immunoassay into a multiresidue method. Finally, immunoaffinity chromatography procedures are useful as methods for sample clean-up, followed by immunochemical detection or more traditional detection methods. 15 refs., 6 figs., 2 tabs.

  4. [Deceased donor liver transplantation].

    PubMed

    Seehofer, D; Schöning, W; Neuhaus, P

    2013-05-01

    Deceased donor liver transplantation is nowadays a routine procedure for the treatment of terminal liver failure and often represents the only chance of a cure. Under given optimal conditions excellent long-term results can be obtained with 15-year survival rates of well above 60 %.In Germany the outcome after liver transplantation has deteriorated since the introduction of an allocation policy, which is based on the medical urgency. At present 25 % of liver graft recipients die within the first year after transplantation. In contrast 1-year survival in most other countries, e.g. in the USA or the United Kingdom is around 90 % and therefore significantly better. Reasons for the inferior results in Germany are on the one hand an increasing number of critically ill recipients and on the other hand an unfavorable situation for organ donation. In comparison with other countries the organ donation rate is low and moreover the risk profile of these donors is above average. This combination of organ shortage and organ allocation represents a big challenge for the future orientation of liver transplantation and creates the potential for conflict. These cannot be solved on a medical basis but require a social consensus.Because of the present inferior results and because of the high expenses of the present system we suggest a discussion on future allocation policies as well as on future centre structures in Germany. In addition to the medical urgency the maximum benefit should also be considered for organ allocation. PMID:23576123

  5. Environmental Immunoassays: Alternative Techniques for Soil and Water Analysis

    USGS Publications Warehouse

    Aga, D.S.; Thurman, E.M.

    1996-01-01

    Analysis of soil and water samples for environmental studies and compliance testing can be formidable, time consuming, and costly. As a consequence, immunochemical techniques have become popular for environmental analysis because they are reliable, rapid, and cost effective. During the past 5 years, the use of immunoassays for environmental monitoring has increased substantially, and their use as an integral analytical tool in many environmental laboratories is now commonplace. This chapter will present the basic concept of immunoassays, recent advances in the development of immunochemical methods, and examples of successful applications of immunoassays in environmental analysis.

  6. DETECTION OF ROTAVIRUS WITH A NEW POLYCLONAL ANTIBODY ENZYME IMMUNOASSAY (ROTAZYME 2) AND A COMMERCIAL LATEX AGGLUTINATION TEXT (ROTALEX): COMPARISON WITH A MONOCLONAL ANTIBODY ENZYME IMMUNOASSAY

    EPA Science Inventory

    A total of 176 human fecal specimens were examined for the presence of rotavirus using four different assays: a monoclonal antibody enzyme immunoassay; the original polyclonal antibody enzyme immunoassay marketed by Abbott Laboratories, Chicago, IL (Rotazyme I); a modification of...

  7. Organ Donor FAQ's: Who Can Be a Donor

    MedlinePLUS

    ... citizens have been organ donors. Can non-resident aliens donate and receive organs? Non-resident aliens can both donate and receive organs in the ... the 12,375 organ donors were non-resident aliens. In this same year, 259 (1%) of the ...

  8. Immunoassay procedures for fiber optic sensors

    NASA Astrophysics Data System (ADS)

    Ligler, Frances S.

    1988-04-01

    There is an increasing need for the development of an ultrasensitive immunoassay for use with fiber optic sensors. These detection systems can be used for such applications as disease diagnosis, detection of chemical and biological warfare agents or drugs of abuse, pollution control, therapeutic monitoring, and explosive detection. This specific program is designed to produce generic chemistries for use with existing fiber optic-based sensors to detect pathogens of particular threat to Army personnel as determined by USAMRIID. The detection system under development involves the attachment of antibodies to an optical fiber at high density. In addition, the immobilization must be achieved in a way which retains the antibody's ability to bind antigen. The functionality of the antibody will be tested through the binding of a labelled antigen. In the future, this assay could incorporate the antibodies developed by the Army for pathogens of particularly military concern.

  9. [Detection of food additives by enzyme immunoassay].

    PubMed

    Yoshida, A; Takagaki, Y

    1995-09-01

    The analysis of synthesized food additives is generally performed by chromatography or spectrophotometry. However, the analytical procedures for natural food additives have been little reported so far because they are difficult to analyse chemically. We have attempted to apply enzyme immunoassay (EIA) to the analysis of natural food additives. Hen egg white lysozyme, as a food preservative, was determined by the competitive EIA, using mouse anti-HEL ascites. Carminic acid (CA), which is the main component of cochineal color, was determined by the competitive EIA, using monoclonal anti-CA antibody. Phycocyanin, which is the main component of spirulina color, was determined by the avidin-biotin sandwich EIA, using double monoclonal anti-phycocyanin antibodies. PMID:7474399

  10. Seroprevalence of human T lymphotropic virus antibodies among healthy blood donors at a tertiary centre in Lagos, Nigeria

    PubMed Central

    Durojaiye, Idris; Akinbami, Akinsegun; Dosunmu, Adedoyin; Ajibola, Sarah; Adediran, Adewumi; Uche, Ebele; Oshinaike, Olajumoke; Odesanya, Majeed; Dada, Akinola; Okunoye, Olaitan

    2014-01-01

    Introduction Transmission of human T-lymphotropic viruses (HTLV) occurs from mother to child, by sexual contact and blood transfusion. Presently, in most centres in Nigeria, there is no routine pre-transfusion screening for HTLV. The study aims to determine the prevalence of HTLV-1 and HTLV-2 among healthy blood donors at a tertiary centre in Lagos. Methods A cross-sectional study was carried out at the blood donor clinic of the Lagos State University Teaching Hospital (LASUTH), Ikeja. About 5mls of venous blood was collected from each subject into a sterile plain bottle after obtaining subject's consent. The serum separated and stored at -200C. Sera were assayed for HTLV by an enzyme-linked immunoassay (ELISA) for the determination of antibodies to HTLV 1 and HTLV -2. Western blot confirmatory testing was done on reactive samples. All donors were also screened for HIV, HBsAg and HCV by rapid kits. Results The seroprevalence of HTLV -1 by ELISA was 1.0% and 0.5% by Western Blot among blood donors. A total of 210 healthy blood donors were enrolled. Only 2 (1.0%) blood donors were repeatedly reactive with ELISA test. On confirmatory testing with Western Blot, 1 (0.5%) blood donor was positive for HTLV. All the healthy blood donors were negative for HIV, HbsAg and HCV. None of the 210 blood donors had been previously transfused; as such no association could be established between transfusion history and HTLV positivity among the blood donors. Conclusion The seroprevalence of HTLV in this environment is low among healthy blood donors. PMID:25328597

  11. Simple immunoassay for detection of PCBs in transformer oil.

    PubMed

    Glass, Thomas R; Ohmura, Naoya; Taemi, Yukihiro; Joh, Takashi

    2005-07-01

    A rapid and inexpensive procedure to detect polychlorinated biphenyls (PCBs) in transformer oil is needed to facilitate identification and removal of PCB contaminated transformers. Here we describe a simple two-step liquid-liquid extraction using acidic dimethyl sulfoxide in conjunction with an immunoassay for detecting PCBs in transformer oil. The process described is faster and simpler than any previous immunoassay while maintaining comparable detection limit and false negative rate. Cross reactivity data, characterizing the immunoassay response to the four Kanechlor technical mixtures of PCBs in oil, are presented. Forty-five used transformer oil samples were analyzed by gas chromatography-high-resolution mass spectrometry and were also evaluated using the immunoassay protocol developed. Results presented show zero false negatives at a 1.4 ppm nominal cutoff for the transformer oils analyzed. PMID:16053103

  12. Whole blood cyclosporin monitoring in liver and heart transplant patients: evaluation of the specificity of a fluorescence polarization immunoassay and an enzyme-multiplied immunoassay technique

    Microsoft Academic Search

    Béatrice Gulbis; Jack Van der Heijden; Harry van As; Philippe Thiry

    1997-01-01

    The specificity of two cyclosporin immunoassays were evaluated. Eleven patients were followed for the first four weeks after heart (n = 3) or liver (n = 8) transplantation. Cyclosporin A (CsA) monitoring was performed concomitantly by a monoclonal fluorescence polarization immunoassay (mFPIA) and enzyme-multiplied immunoassay technique (EMIT®) during this period. For several patients, cyclosporin monitoring was also performed by high

  13. Relationship Between Everolimus Blood Concentration Assessed Using the Innofluor Certican Fluorescence Polarization Immunoassay and the Architect i System Sirolimus Chemiluminescent Microparticle Immunoassay

    Microsoft Academic Search

    L. Coentrão; C. Carvalho; S. Sampaio; J. G. Oliveira; M. I. Pestana

    2010-01-01

    Everolimus, an immunosuppressive macrolide derivative of sirolimus, has a narrow therapeutic index and variable bioavailability. Assessment of blood concentration of everolimus is necessary to improve immunosuppressive efficacy without increasing potential adverse effects. Recently, Seradyn, Inc (Indianapolis, Indiana) introduced a fluorescence polarization immunoassay (Innofluor Certican Fluorescent Polarization Immunoassay [FPIA]) for quantitation of everolimus blood concentration. This immunoassay has concentration-dependent cross-reactivity with

  14. Management of young blood donors.

    PubMed

    Newman, Bruce H

    2014-07-01

    The emphasis on high-school blood drives and acceptance of 16-year-old blood donors led to more research on physiologic and psychological ways to decrease vasovagal reaction rates in young blood donors and to increase donor retention. Research on how to accomplish this has been advantageous for the blood collection industry and blood donors. This review discussed the current situation and what can be done psychologically, physiologically, and via process improvements to decrease vasovagal reaction rates and increase donor retention. The donation process can be significantly improved. Future interventions may include more dietary salt, a shorter muscle tension program to make it more feasible, recommendations for post-donation muscle tension / squatting / laying down for lightheadedness, more donor education by the staff at the collection site, more staff attention to donors with fear or higher risk for a vasovagal reaction (e.g. estimated blood volume near 3.5 l, first-time donor), and a more focused donation process to ensure a pleasant and safer procedure. PMID:25254024

  15. Donor Matching for Allogenic Transplant

    MedlinePLUS

    ... a stem cell transplant? Weigh the risks before transplant Types of stem cell transplants for treating cancer Sources of stem cells for ... How well the donor’s and recipient’s HLA tissue types match plays a large part in whether the transplant will work. A match is better when all ...

  16. Management of Young Blood Donors

    PubMed Central

    Newman, Bruce H.

    2014-01-01

    Summary The emphasis on high-school blood drives and acceptance of 16-year-old blood donors led to more research on physiologic and psychological ways to decrease vasovagal reaction rates in young blood donors and to increase donor retention. Research on how to accomplish this has been advantageous for the blood collection industry and blood donors. This review discussed the current situation and what can be done psychologically, physiologically, and via process improvements to decrease vasovagal reaction rates and increase donor retention. The donation process can be significantly improved. Future interventions may include more dietary salt, a shorter muscle tension program to make it more feasible, recommendations for post-donation muscle tension / squatting / laying down for lightheadedness, more donor education by the staff at the collection site, more staff attention to donors with fear or higher risk for a vasovagal reaction (e.g. estimated blood volume near 3.5 l, first-time donor), and a more focused donation process to ensure a pleasant and safer procedure. PMID:25254024

  17. Detection of narcotics with an immunoassay film badge

    SciTech Connect

    Lukens, H.R. [Diametrix Detectors, Inc., San Diego, CA (United States)

    1993-12-31

    Efficient personnel performance, a major requirement for a safe nuclear industry, is jeopardized where personnel use narcotics. However, detection of narcotics at nuclear plants is a challenge. The unique specificity and sensitivity of an immunoassay has been implemented in the form of a small, dry immunoassay film badge (IFB) for the detection of vapors emitted by narcotics. The device is suitable as an area monitor, and its characteristics are suitable for use as a breath monitor for the detection of drug use.

  18. Colorimetric immunoassay chip based on gold nanoparticles and gold enhancement

    Microsoft Academic Search

    Kin Fong Lei; Yoki K. C. Butt

    2010-01-01

    A colorimetric immunoassay chip has been developed based on gold nanoparticles for indicating the antibody–antigen binding\\u000a activity and gold enhancement for amplifying the specific binding signal. Our investigations showed that the results of immunoassay\\u000a can be represented by the level of color intensity. They were easily observed by a regular camera or naked eye, which is not\\u000a needed of sophisticated

  19. Simplifying site assessment of PAH using immunoassay directed field screening

    SciTech Connect

    Mullenix, M.C.; Hudak, R.T.; Melby, J.M.; Stave, J.W. [Strategic Diagnostics Inc., Newark, DE (United States)

    1995-12-31

    Polycyclic aromatic hydrocarbons (PAH) are carcinogenic and mutagenic chemicals found in combustion products and industrial waste materials. The carcinogenic nature of PAHs has led state and federal agencies to control their levels in the environment. Until recently, site assessment of PAH levels in soil was limited by the high cost and long turnaround time associated with analysis methods used in commercial analytical laboratories. The recent development of PAH immunoassays provides a rapid and cost effective alternative to the traditional analytical methods. One such immunoassay was developed as a part of the D TECH tm line of environmental detection systems. This competitive immunoassay uses anti-PAH antibodies immobilized on latex particles. Antibody binding to an enzyme labeled PAH analog is inhibited by free PAH extracted from soil samples or contained in water samples. The immunoassay detects the majority of compounds on the EPA list of 16 PAH priority pollutants below the ppm level without cross reacting with BTEX, PCBs and other similar compounds. Field samples of PAH were collected at both petrogenic and pyrolytic sites of contamination and the PAH concentrations were determined by both the immunoassay and the EPA SW-846 GC/MS method 8270. Test results correlated between the two methods and the low number of false negative and false positive results confirmed the assay`s specificity for PAH. The immunoassay provides the advantages of rapid, on site analysis, and minimum sample preparation. Use of the immunoassay results in a significant savings in the cost of analysis because the cost per assay is lower than commercial analysis and only positive samples require additional confirmation by instrumental techniques. The simple format of the immunoassay allows personnel with minimal training to reliably and accurately determine the PAH content of soils.

  20. Immunoassay of DNA modified by ultraviolet radiation: a review

    SciTech Connect

    Strickland, P.T.

    1985-01-01

    The present review concentrates on studies from several laboratories using immunological assays to detect and quantitate alterations induced in DNA by ultraviolet (UV) radiation. The initial section summarizes the available information on antibody specificity since conclusions drawn from immunoassays depend critically on this information. The subsequent section discusses the use of immunoassays in several areas of photobiological research, including kinetics of DNA photoproduct repair in cultured cells and distribution and repair of photoproducts in skin.

  1. Capillary Electrophoresis-Based Immunoassays: Principles & Quantitative Applications

    PubMed Central

    Moser, Annette C.; Hage, David S.

    2013-01-01

    The use of capillary electrophoresis as a tool to conduct immunoassays has been an area of increasing interest over the last decade. This approach combines the efficiency, small sample requirements, and relatively high speed of CE with the selectivity of antibodies as binding agents. This review examines the various assay formats and detection modes that have been reported for these assays, along with some representative applications. Most CE immunoassays in the past have employed homogeneous methods in which the sample and reagents are allowed to react in solution. These homogeneous methods have been conducted as both competitive binding immunoassays and as non-competitive binding immunoassays. Fluorescent labels are most commonly used for detection in these assays, but enzyme labels have also been utilized for such work. Some additional work has been performed in CE immunoassays with heterogeneous methods in which either antibodies or an analog of the analyte is immobilized to a solid support. These heterogeneous methods can be used for the selective isolation of analytes prior to their separation by CE or to remove a given species from a sample/reagent mixture prior to analysis by CE. These CE immunoassays can be used with a variety of detection modes, such as fluorescence, UV/visible absorbance, chemiluminescence, electrochemical measurements, mass spectrometry, and surface plasmon resonance. PMID:18646279

  2. Seroepidemiology of infection with Toxoplasma gondii in healthy blood donors of Durango, Mexico

    PubMed Central

    Alvarado-Esquivel, Cosme; Mercado-Suarez, Miguel Francisco; Rodríguez-Briones, Alfredo; Fallad-Torres, Laura; Ayala-Ayala, Julio Octavio; Nevarez-Piedra, Luis Jorge; Duran-Morales, Ehecatl; Estrada-Martínez, Sergio; Liesenfeld, Oliver; Márquez-Conde, José Ángel; Martínez-García, Sergio Arturo

    2007-01-01

    Background Toxoplasma gondii (T. gondii) infection in blood donors could represent a risk for transmission in blood recipients. There is scarce information about the epidemiology of T. gondii infection in blood donors in Mexico. Therefore, we sought to determine the prevalence of T. gondii infection and associated socio-demographic and behavioral characteristics in a population of healthy blood donors of Durango City, Mexico. Methods Four hundred and thirty two blood donors in two public blood banks of Durango City, Mexico were examined for T. gondii infection between August to September 2006. Blood donors were tested for anti-T. gondii IgG and IgM antibodies by using enzyme-linked immunoassays (Diagnostic Automation Inc., Calabasas, CA, USA). Socio-demographic and behavioral characteristics from each participant were also obtained. Results Thirty two (7.4%) of 432 blood donors had IgG anti-T. gondii antibodies. Eight (1.9%) of them had also IgM anti-T. gondii antibodies. Multivariate analysis using logic regression showed that T. gondii infection was associated with the presence of cats at home (adjusted OR = 3.81; 95% CI: 1.45–10.01). The age group of 45–60 years showed a significantly higher frequency of T. gondii infection than the group of 25–34 years (p = 0.02). Blood donors without education had a significantly higher frequency of infection (15.8%) than those with 13–19 years of education (4.5%) (p = 0.04). Other characteristics of blood donors including male gender, consumption of undercooked meat or blood transfusion did not show an association with infection. Conclusion The prevalence of T. gondii infection in healthy blood donors of Durango City, Mexico is lower than those reported in blood donors of south and central Mexico, and is one of the lowest reported in blood donors worldwide. T. gondii infection in our blood donors was most likely acquired by contact with cats. Prevalence of infection increased with age and decreased with educational level. PMID:17629901

  3. [Altruism and the donor].

    PubMed

    Langlois, A

    1991-08-01

    On December 20, 1988, the government of France passed a law to protect people who voluntarily participate in biomedical research. This article makes extensive reference to a major study, titled From Biology to Ethics, by Jean Bernard, a well-respected authority in the field of bioethics. The author looks at models proposed by Bernard, as examples for health volunteers, in particular, the blood donor and the self-experimenter. To set the tone of the article, she recalls the concept of altruism, as first proposed by Auguste Comte, then makes a linkage between his philosophy and Bernard's point of view. By trial and error, in their discussions, various ethics committees and the French State Council have agreed upon what constitutes fair compensation under the law. Unlike their Canadian counterparts, medical researchers in France have free access to volunteers who are not in perfect health--e.g., the elderly, people suffering from kidney deficiency, cirrhosis of the liver, etc.--but these "experimental subjects" receive no monetary compensation. Thus, healthy and less-than-healthy volunteers do not receive equal treatment under the law. This inequity, added to the fear of what amounts to a tax on the human body and the difficulty of ensuring just compensation, is giving rise to a great deal of uncertainty. PMID:1878857

  4. Fluorescence polarization immunoassays for metal ions.

    PubMed

    Johnson, David K

    2003-05-01

    Antibodies raised against a given metal ion complex of a polyaminopolycarboxylate chelating agent can display specificity for the immunizing chelate and, when used in conjunction with a fluorophore-labeled analog of that chelate, can form the basis for highly sensitive and specific methods for detecting that metal ion by competitive inhibition fluorescence polarization immunoassay (FPIA). Chelate complexes of ethylenediamine-N,N,N',N'- tetraacetic acid (EDTA) and of a hetrocyclic ring-substituted derivative of diethylenetriamine-N, N', N"-triacetic acid (DTTA) have been used to configure such assays for the heavy metal ions lead(II) and cadmium(II) respectively. Limits of detection for the 1:1 metal chelates under ideal conditions are 20 ppt for lead(II) and below 100 ppt for cadmium(II). Standard curves for 0 - 100 nM cadmium (II) chelate can be constructed in the presence of fixed 250 nM concentrations of the corresponding, potentially cross-reactive chelates of zinc(II), copper(II) and mercury(II). Cross-reactivity of the lead (II) FPIA with 15 non-target metals is below 0.2% in all cases except for mercury(II) (0.37%). These characteristics have allowed the development of FPIA methods for the quantitative analysis of lead in a variety of samples relevant to environmental monitoring, including soil, dust, solid wastes and drinking water. Although applied thus far to heavy metals that are of concern as toxic contaminants in the environment, anti-chelate FPIA methods are also in principle applicable to a wide variety of other metal ions, including precious metals and various transition and main group elements used or monitored in a range of industrial applications. As conventional methods for trace metal analysis based on atomic spectroscopy are relatively slow, expensive and cumbersome, anti-chelate FPIA methods have the potential to supplant many existing techniques and in so doing extend the use of immunoassay technology beyond the biomedical, veterinary and agricultural spheres in which it has historically found use. PMID:12678703

  5. Multiplex lateral flow immunoassay for mycotoxin determination.

    PubMed

    Song, Suquan; Liu, Na; Zhao, Zhiyong; Njumbe Ediage, Emmanuel; Wu, Songling; Sun, Changpo; De Saeger, Sarah; Wu, Aibo

    2014-05-20

    A new lateral flow immunoassay (LFA) is proposed for qualitative and/or semiquantitative determination of aflatoxin B1 (AFB1), zearalenone (ZEA), deoxynivalenol (DON), and their analogues (AFs, ZEAs, DONs) in cereal samples. Each of the mycotoxin specific antibody was class specific and there was no cross reactivity to other groups of compounds. The visual limits of detection (vLOD) of the strip were 0.03, 1.6, and 10 ?g/kg for AFB1, ZEA and DON, respectively. The calculated limits of detection (cLOD) were 0.05, 1, and 3 ?g/kg, respectively. Meanwhile the cutoff values were achieved at 1, 50, and 60 ?g/kg for AFB1, ZEA and DON, respectively. Recoveries ranged from 80% to 122% and RSD from 5% to 20%. Both the vLOD and cLOD for the three mycotoxins were lower than the EU maximum levels. Analysis of naturally contaminated maize samples resulted in a good agreement between the multiplex LFA and LC-MS/MS (100% for DONs and AFs, and 81% for ZEAs). Careful analysis of the results further explained the general overestimation of LFA compared to chromatographic methods for quantification of mycotoxins. PMID:24745689

  6. A new modular chemiluminescence immunoassay analyser evaluated.

    PubMed

    Ognibene, A; Drake, C J; Jeng, K Y; Pascucci, T E; Hsu, S; Luceri, F; Messeri, G

    2000-03-01

    Thyrotropin (TSH), free thyroxine (fT4) and testosterone assays have been used as a probe to evaluate the performances of a new modular chemiluminescence (CL) immunoassay analyser, the Abbott Architect 2000. The evaluation was run in parallel on other systems that use CL as the detection reaction: DPC Immulite, Chiron Diagnostics ACS-180 and ACS Centaur (TSH functional sensitivity only). TSH functional sensitivity was 0.0012, 0.009, 0.033 and 0.039 mU/I for the Architect, Immulite, ACS Centaur and ACS-180, respectively. Testosterone functional sensitivity was 0.38, 3.7 and 2.0 nmol/l for Architect, Immulite and ACS-180, respectively. Good correlation was obtained between the ACS-180 and Architect for all assays. The Immulite correlation did not agree well with the Architect or ACS-180 for fT4 and testosterone but was in good agreement for TSH. Regarding fT4 and testosterone, equilibrium dialysis and isotopic dilution gas-chromatography mass-spectrometry (GC-MS) respectively were used as reference methods. For both within- and between-run precision, the Architect showed the best reproducibility for all three analytes (CV < 6%). PMID:10905763

  7. Why Minority Donors Are Needed

    MedlinePLUS

    ... Why Donate RELATED INFORMATION Minority Focused Grantee Publications Organ Donation Process Enrolling as a Donor Trying to Save ... transplantation for everyone. > More about African Americans and organ donation > More about Asians, and Native Hawaiians and other ...

  8. Being a Living Donor: Risks

    MedlinePLUS

    ... after donation or later. You and/or your recipient may face surgical complications. The transplanted organ may ... may change the relationship you have with the recipient. Living donors must be made aware of the ...

  9. Donor states in inverse opals

    SciTech Connect

    Mahan, G. D. [Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2014-09-21

    We calculate the binding energy of an electron bound to a donor in a semiconductor inverse opal. Inverse opals have two kinds of cavities, which we call octahedral and tetrahedral, according to their group symmetry. We put the donor in the center of each of these two cavities and obtain the binding energy. The binding energies become very large when the inverse opal is made from templates with small spheres. For spheres less than 50?nm in diameter, the donor binding can increase to several times its unconfined value. Then electrons become tightly bound to the donor and are unlikely to be thermally activated to the semiconductor conduction band. This conclusion suggests that inverse opals will be poor conductors.

  10. Resonant tunneling through donor molecules

    Microsoft Academic Search

    A. K. Geim; T. J. Foster; A. Nogaret; N. Mori; P. J. McDonnell; N. La Scala Jr.; P. C. Main; L. Eaves

    1994-01-01

    We discuss the origin of zero-dimensional states, which give rise to resonant structure at the current onset in tunneling devices. The states can be identified as being due to random pairs of shallow donors.

  11. Complications of Laparoscopic Donor Nephrectomy

    Microsoft Academic Search

    Alexei Wedmid; Michael A. Palese

    \\u000a “Laparoscopic donor nephrectomy is a unique surgical procedure due to the fact that the surgeon is operating on a healthy\\u000a individual in order to benefit another patient he or she is unlikely managing, with a potential for complications ensuing\\u000a in both the donor and the recipient patients. Overall surgical technique, anatomic considerations, and perioperative management\\u000a remain important for minimizing the

  12. Donor selection in heart transplantation

    PubMed Central

    Emani, Sitaramesh; Sai-Sudhakar, Chittoor B.; Higgins, Robert S. D.; Whitson, Bryan A.

    2014-01-01

    There is increased scrutiny on the quality in health care with particular emphasis on institutional heart transplant survival outcomes. An important aspect of successful transplantation is appropriate donor selection. We review the current guidelines as well as areas of controversy in the selection of appropriate hearts as donor organs to ensure optimal outcomes. This decision is paramount to the success of a transplant program as well as recipient survival and graft function post-transplant. PMID:25132976

  13. Motivations for Giving of Alumni Donors, Lapsed Donors and Non-Donors: Implications for Christian Higher Education

    ERIC Educational Resources Information Center

    Rugano, Emilio Kariuki

    2011-01-01

    This descriptive and causal comparative study sought to identify motivations for alumni donor acquisition and retention in Christian institutions of higher learning. To meet this objective, motivations for alumni donors, lapsed donors, and non-donors were analyzed and compared. Data was collected through an electronic survey of a stratified sample…

  14. DEVELOPMENT OF A CLASS-SELECTIVE ENZYME IMMUNOASSAY FOR URINARY PHENOLIC GLUCURONIDES. (R825433)

    EPA Science Inventory

    Class-selective immunoassays for the measurement of glucuronides in human urine can aid evaluation of human exposure to complex mixtures of xenobiotics. Therefore, an enzyme immunoassay (EIA) for the group-selective detection of phenolic ...

  15. SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION PROGRAM DEMONSTRATION PLAN FOR WESTINGHOUSE BIO-ANALYTIC SYSTEMS PENTACHLOROPHENOL IMMUNOASSAYS

    EPA Science Inventory

    This plan provides a detailed design and description of the demonstration and evaluation program for the Westinghouse Bio-Analytic Systems immunoassay technologies specific for the analysis of pentachlorophenol. he immunoassays measure parts per billion concentrations of pentachl...

  16. SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION (SITE) REPORT FOR THE WESTINGHOUSE BIOANALYTICAL SYSTEMS PENTACHLOROPHENOL (PCP) IMMUNOASSAYS

    EPA Science Inventory

    The results of the demonstration of two Westinghouse Bio-Analytic Systems (WBAS) immunoassay technologies are described in this report. The immunoassays measure parts per billion concentrations of pentachlorophenol in environmental water samples. The study was conducted under the...

  17. Enhancement of Immunoassay's Fluorescence and Detection Sensitivity Using Three-Dimensional Plasmonic Nano-Antenna-Dots

    E-print Network

    the average fluorescence of an immunoassay of Protein A and human immunoglo- bulin G (IgG) by over 7400-fold range, and ease to manufacture, the giant enhancement in immunoassay's fluorescence and detection

  18. Blood Donation by Elderly Repeat Blood Donors

    PubMed Central

    Zeiler, Thomas; Lander-Kox, Jutta; Alt, Timo

    2014-01-01

    Summary Background Upper age limits for blood donors are intended to protect elderly blood donors from donor reactions. However, due to a lack of data about adverse reactions in elderly blood donors, upper age limits are arbitrary and vary considerably between different countries. Methods Here we present data from 171,231 voluntary repeat whole blood donors beyond the age of 68 years. Results Blood donations from repeat blood donors beyond the age of 68 years increased from 2,114 in 2005 to 38,432 in 2012 (from 0,2% to 4.2% of all whole blood donations). Adverse donor reactions in repeat donors decreased with age and were lower than in the whole group (0.26%), even in donors older than 71 years (0.16%). However, from the age of 68 years, the time to complete recovery after donor reactions increased. Donor deferrals were highest in young blood donors (21.4%), but increased again in elderly blood donors beyond 71 years (12.6%). Conclusion Blood donation by regular repeat blood donors older than 71 years may be safely continued. However, due to a lack of data for donors older than 75 years, blood donation in these donors should be handled with great caution. PMID:25254019

  19. Self-Assembled Monolayers for MALDI-TOF Mass Spectrometry for Immunoassays of Human Protein

    E-print Network

    Mrksich, Milan

    Self-Assembled Monolayers for MALDI-TOF Mass Spectrometry for Immunoassays of Human Protein spinal fluids from patients diagnosed with mul- tiple sclerosis. The SAMDI-TOF immunoassay, which much promise for diagnostic immunoassays.5,6 By eliminating the need for labeled reagents, these label

  20. Kinetics of protein binding in solid-phase immunoassays: Theory Konstantin V. Klenin

    E-print Network

    Langowski, Jörg

    Kinetics of protein binding in solid-phase immunoassays: Theory Konstantin V. Klenin Division 2005; accepted 13 April 2005; published online 7 June 2005 In a solid-phase immunoassay, binding. Various immunoassay geometries are considered, in particular, the case when the reaction is carried out

  1. 1602 ANALYTICAL CHEMISTRY, VOL. 51, NO. 11, SEPTEMBER 1979 Laser Fluorescence Immunoassay of Insulin

    E-print Network

    Zare, Richard N.

    1602 ANALYTICAL CHEMISTRY, VOL. 51, NO. 11, SEPTEMBER 1979 Laser Fluorescence Immunoassay-6). It is our goal to combine laser fluorimetry with fluorescence immunoassay to achieve an attractive alternative to radioimmunoassay. In immunoassay, unlabeled antigen (Ag) competes with labeled antigen (Ag

  2. High-Speed Interferometric Detection of Label-Free Immunoassays on the

    E-print Network

    Nolte, David D.

    High-Speed Interferometric Detection of Label-Free Immunoassays on the Biological Compact Disc Ming-support immunoassays based on optical detection enable small spot sizes that in principle could be scaled down optical detection into a sensitive and scalable immunoassay platform (1, 2). The 1st BioCD demonstration

  3. Immunoassay on Free-Standing Electrospun Dapeng Wu, Daewoo Han, and Andrew J. Steckl*

    E-print Network

    Steckl, Andrew J.

    Immunoassay on Free-Standing Electrospun Membranes Dapeng Wu, Daewoo Han, and Andrew J. Steckl of immunoassay, electrospun membranes can be thought as the threadlike self-assembling of nano/ microbeads-HSA and HSA-FITC as an immunoassay model, a linear detection range from 500 ng/mL down to 1 ng/mL is obtained

  4. Electrophoretic build-up of multi nanoparticle array for a highly sensitive immunoassay

    E-print Network

    Hammock, Bruce D.

    Electrophoretic build-up of multi nanoparticle array for a highly sensitive immunoassay Jin-Hee Han Accepted 17 August 2012 Available online 6 September 2012 Keywords: Nanoarray Immunoassay Electrophoretic immunoassays to smaller sizes is to immobilize the biological molecules to nanometer-scaled spots. To overcome

  5. 333Biotechnol. Prog. 1995, 11, 333-341 Noncompetitive Immunoassays Using Bifunctional Unilamellar

    E-print Network

    Kilpatrick, Peter K.

    333Biotechnol. Prog. 1995, 11, 333-341 Noncompetitive Immunoassays Using Bifunctional Unilamellar the specific signal, the immunoassay protocol was optimized with respect to (1)the type and concentration) the incubation temperature. The bifunctional vesicles were used in a noncompetitive immunoassay to detect d

  6. Measuring multiple hormones from a single water sample using enzyme immunoassays

    E-print Network

    Hofmann, Hans A.

    Measuring multiple hormones from a single water sample using enzyme immunoassays Celeste E. Kidd F2a 11-Ketotestosterone Astatotilapia burtoni Enzyme immunoassay EIA Teleost Cichlid Steroid radioimmuno- assay (RIA) or enzyme immunoassay (EIA) is becoming widely used in teleost research. Commercial

  7. On-Chip Native Gel Electrophoresis-Based Immunoassays for Tetanus Antibody and Toxin

    E-print Network

    Herr, Amy E.

    On-Chip Native Gel Electrophoresis-Based Immunoassays for Tetanus Antibody and Toxin Amy E. Herr device, we have developed a microanalytical platform for performing electrophoresis- based immunoassays. The microfluidic immunoassays are performed by gel electrophoretic separation and quanti- tation of bound

  8. FREE AND CONJUGATED ZERANOL RESIDUES DETERMINED BY RADIO-IMMUNOASSAY IN URINE AND PLASMA OF CALVES

    E-print Network

    Paris-Sud XI, Université de

    FREE AND CONJUGATED ZERANOL RESIDUES DETERMINED BY RADIO-IMMUNOASSAY IN URINE AND PLASMA OF CALVES (part per billion) range. Recently, radio-immunoassays (RIA) for zeranol have been described (Dixon) before the radio- immunoassay. In this study, we have measured free and conju- #12;gated zeranol residues

  9. Immunoassay for mercury in seafood and animal tissues

    SciTech Connect

    Carlson, L.; Holmquist, B.; Ladd, R.; Riddell, M. [BioNebraska, Inc., Lincoln, NE (United States)

    1995-12-01

    Methylmercury accumulates to high levels in the tissues of fish and other animals through biomagnification. Since methylmercury is extremely toxic, it is important to identify fish or animal tissues with mercury levels too high for human consumption. Current methods for the analysis of mercury are expensive and time- consuming, and they must be performed in a laboratory setting. In this study, a rapid and inexpensive mercury-specific immunoassay developed by BioNebraska was used to measure total mercury in tissue following acid digestion and methylmercury decomposition. A good correlation was obtained between the immunoassay and cold vapor atomic absorption spectrophotometry (CVAAS). Use of the mercury immunoassay will facilitate the rapid screening of large numbers of tissue samples.

  10. Potential applications of immunoassays in studies of flatfish recruitment

    NASA Astrophysics Data System (ADS)

    Feller, Robert J.

    The fisheries recruitment-stock problem, a lack of correlation between measures of reproductive output of the parent stock and recruitment to the fishery, has several potential biotic and abiotic causes. Immunoassays may be useful in examining several aspects of this and several other problems in flatfish ecology: stock identification, parasitism and disease, and trophic interactions. Given stage-specific antisera capable of recognozing antigenic moieties of, for instance, eggs, larvae, or newly-settled juveniles, it is possible to screen stomach contents of many putative predators ( e.g., shrimp or crabs) rapidly for the presence and amounts of platfish prey. This trophic application of immunological methods has great promise for measuring loss of potential recruits to predation. All immunoassays are limited by the quality of antisera used and the researcher's ability to interpret quantitative data in an ecologically meaningful way. Key references for applications of immunoassays in fish-related questions are provided with recommendations for their utilization.

  11. Detection of bound residues in soils by sandwich-immunoassay

    SciTech Connect

    Dosch, M.; Weller, M.G.; Niessner, R. [Technical Univ. of Munich (Germany). Institute of Hydrochemistry

    1995-12-31

    Immunoassays are useful analytical instruments for the detection of many environmental compounds. This method was not introduced for the detection of non-extractable compounds in soil. So-called ``bound residues`` consist of a soil component, e.g. humic acids and an irreversibly bound pollutant. Because of the complexity of those macromolecules conventional analytical methods in general do not work. Enzyme immunoassays, in contrast, seem to have a large potential for applications and further developments in this field. The use of antibodies with high affinity to the analytes makes a selective detection of environmental pollutants possible. With the development of an enzyme-labeled sandwich-immunoassay polycyclic aromatic hydrocarbons (PAHs) irreversibly bound to humic acids were determined for the first time.

  12. Studies on the applications of an immunoassay for mercury

    SciTech Connect

    Water, L.C.; Counts, R.W.; Smith, R.R. [Oak Ridge National Lab., TN (United States)

    1996-10-01

    Immunoassays are rapidly becoming a significant component of the arsenal of field analytical methods. Validation of such alternative methods is necessary for their acceptance by the regulatory agencies and potential users. As part of a program to evaluate the performance of such methods, we have examined the capacity of the BiMelyze (BioNebraska, Inc.) immunoassay method to measure mercury in soil, sludge and water. Results from the analysis of contaminated soil samples showed the immunoassay to perform as well as either X-ray fluorescence or neutron activation analysis. The method was also shown to be capable of measuring as little as 2.5 ppm mercury in sludge from a waste water treatment plant. In conjunction with a bacterial genetic toxicity assay (Xenometrix, Inc.), it was also indicated to have a specificity for bioavailable mercury in a contaminated waste water sample.

  13. Estimation of sensitivity and specificity of several Trypanosoma cruzi antibody assays in blood donors in Argentina

    PubMed Central

    Remesar, Mirta C.; Gamba, Cecilia; Colaianni, Ivana F.; Puppo, Mónica; Sartor, Paula A.; Murphy, Edward L.; Neilands, Torsten B.; Ridolfi, María A.; Leguizamón, M. Susana; Kuperman, Silvina; del Pozo, Ana E.

    2010-01-01

    BACKGROUND The absence of a gold standard test for Trypanosoma cruzi antibodies represents a problem not only for the evaluation of screening tests, but also for appropriate blood donor counseling. The aim of this study was to estimate the sensitivity and specificity of multiple blood donor screening tests for T. cruzi antibodies in Argentina. STUDY DESIGN AND METHODS From June 2006 to March 2007 a sample of 1455 blood donors was recruited from two blood banks in Chaco province, an area of Argentina with highly endemic T. cruzi infection. Samples were tested by three epimastigote lysate enzyme immunoassays (EIAs), one recombinant antigen EIA, two indirect hemagglutination assay (IHA) tests, a particle agglutination assay (PA), and a research trans-sialidase inhibition assay (TIA). Sensitivity and specificity were estimated using latent class analysis (LCA). RESULTS LCA estimated the consensus prevalence of T. cruzi infection at 24.5%. Interassay correlation was higher among the four EIA tests and TIA compared to IHA tests. Assay sensitivities varied from 96 to 99.7 for different EIAs, 91% for TIA, 84% for PA, and 66 to 74% for IHA tests. Relative to the LCA, assay specificities were from 96% to almost 100%. CONCLUSION Based on the comparison of several tests in a large population from an endemic area for T. cruzi infection, our data showed an adequate sensitivity for EIA tests in contrast to PA and IHA assays. The latter tests should no longer be used for blood donor screening. PMID:19903291

  14. Variability in telavancin cross-reactivity among vancomycin immunoassays.

    PubMed

    McConeghy, Kevin W; Liao, Siyun; Clark, Douglas; Worboys, Philip; Barriere, Steven L; Rodvold, Keith A

    2014-12-01

    Telavancin is a semisynthetic lipoglycopeptide with a dual mechanism of action against Gram-positive pathogens. Two brief reports have suggested potential cross-reactivity of telavancin with the vancomycin particle-enhanced turbidometric immunoassay (PETIA). The purpose of this study was to evaluate several commercially available vancomycin immunoassays (fluorescence polarization [FPIA], enzyme-multiplied immunoassays [EMIT], PETIA, and chemiluminescent immunoassay [CMIA]) for cross-reactivity with telavancin. Seven sites were selected to analyze serum samples for vancomycin. Each site received a set of samples (n = 18) which combined drug-free serum with telavancin, 7-OH telavancin metabolite, or vancomycin. Immunoassays demonstrating potential cross-reactivity were further evaluated by sending a duplicate sample set to multiple laboratories. Cross-reactivity was defined as the percent theoretical concentration (reported concentration/theoretical concentration × 100). No cross-reactivity was seen with FPIA or EMIT. Within the theoretical concentration range of 5 to 120 ?g/ml of telavancin, the Synchron PETIA system reported vancomycin concentrations ranging from 4.7 to 54.2 ?g/ml compared to vancomycin concentrations from 1.1 to 5.6 ?g/ml for the Vista PETIA system. The Architect CMIA system reported vancomycin concentrations in the range of 0.27 to 0.97 ?g/ml, whereas Advia Centaur XP CMIA reported vancomycin concentrations between 1.6 and 31.6 ?g/ml. The Architect CMIA immunoassay had the lowest percent cross-reactivity (0.8 to 5.4%), while the Synchron PETIA immunoassay demonstrated the highest percent cross-reactivity (45.2 to 53.8%). Telavancin samples measured by liquid chromatography-mass spectroscopy were within 93.9 to 122% of theoretical concentrations. Vancomycin concentrations were not measured in any 7-OH telavancin-spiked sample. Vancomycin concentrations measured by liquid chromatography-mass spectroscopy were within 57.2 to 113% of theoretical concentrations. PETIA and CMIA measured vancomycin concentrations in telavancin-spiked samples. Significant variability in percent cross-reactivity was observed for each platform regardless of immunoassay method. PMID:25223996

  15. Robust detection of peak signals for lateral flow immunoassays

    NASA Astrophysics Data System (ADS)

    Kim, Jongwon; Kim, Jong Dae; Nahm, Kie Bong; Choi, Eui Yul; Lee, Geumyoung

    2011-02-01

    Template matching method is presented to identify the peaks from the scanned signals of lateral flow immunoassay strips. The template is composed of two pulses separated by the distance of the control and the target ligand line in the assay, and is convolved with the scanned signal to deliver the maximum at the center of the two peaks. The peak regions were identified with the predefined distances from the center. Glycosylated haemoglobin immunoassay strips and fluorescent strip readers from Boditechmed Inc. were tested to estimate the lot and reader variations of the concentration measurands. The results showed the robustness of the propose method.

  16. 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.

  17. Enzyme linked immunoassay with stabilized polymer saccharide enzyme conjugates

    DOEpatents

    Callstrom, M.R.; Bednarski, M.D.; Gruber, P.R.

    1997-11-25

    An improvement in enzyme linked immunoassays is disclosed wherein the enzyme is in the form of a water soluble polymer saccharide conjugate which is stable in hostile environments. The conjugate comprises the enzyme which is linked to the polymer at multiple points through saccharide linker groups. 19 figs.

  18. Highly sensitive homogenous chemiluminescence immunoassay using gold nanoparticles as label

    NASA Astrophysics Data System (ADS)

    Luo, Jing; Cui, Xiang; Liu, Wei; Li, Baoxin

    2014-10-01

    Homogeneous immunoassay is becoming more and more attractive for modern medical diagnosis because it is superior to heterogeneous immunoassay in sample and reagent consumption, analysis time, portability and disposability. Herein, a universal platform for homogeneous immunoassay, using human immunoglobulin G (IgG) as a model analyte, has been developed. This assay relies upon the catalytic activity of gold nanoparticles (AuNPs) on luminol-AgNO3 chemiluminescence (CL) reaction. The immunoreaction of antigen and antibody can induce the aggregation of antibody-functionalized AuNPs, and after aggregation the catalytic activity of AuNPs on luminol-AgNO3 CL reaction is greatly enhanced. Without any separation steps, a CL signal is generated upon addition of a trigger solution, and the CL intensity is directly correlated to the quantity of IgG. The detection limit of IgG was estimated to be as low as 3 pg/mL, and the sensitivity was better than that of the reported AuNPs-based CL immunoassay for IgG.

  19. CAPILLARY ELECTROPHORESIS IMMUNOASSAY FOR 2,4-DICHLOROPHENOXYACETIC ACID

    EPA Science Inventory

    A capillary electrophoresis (CE) immunoassay format for 2,4-dichlorophenoxyacetic acid (2,4-D) is demonstrated. A fluorescent labeled 2,4-D analog competes with the analyte of interest for a finite number of binding sites provided by anti-2,4-D monoclonal antibodies. CE then pr...

  20. Establishment of norvancomycin fluorescence polarization immunoassay for therapeutic drug monitoring

    Microsoft Academic Search

    Xiao-Jie Wu; Jing Zhang; Ji-Cheng Yu; Guo-Ying Cao; Yao-Guo Shi; Ying-Yuan Zhang; Ming-Gui Wang; J Zhang

    2012-01-01

    To establish a rapid and simple fluorescence polarization immunoassay method for determination of norvancomycin serum concentration, we collected 300 serum samples from the patients receiving norvancomycin in the hospitals localized in Shanghai, China. The drug concentrations were measured by the established HPLC method and FPIA with vancomycin kit. A FPIA algorithm for the determination of norvancomycin concentration was established according

  1. Development of a Fluorescence Polarization Immunoassay for Polycyclic Aromatic Hydrocarbons

    Microsoft Academic Search

    Irina Yu Goryacheva; Sergei A. Eremin; Ekaterina A. Shutaleva; Miloslav Suchanek; Reinhard Niessner; Dietmar Knopp

    2007-01-01

    A fluorescence polarization immunoassay for detection of polycyclic aromatic hydrocarbons (PAHs) was developed. Fluorescein?labeled tracers based on different PAHs were synthesized and studied in order to achieve a high sensitivity using both monoclonal and polyclonal antibodies. The application of different combinations of antibody tracer pairs allows to separately determine groups of small and large PAHs or to realize a class?specific

  2. Magnetic Beads-based Bioelectrochemical Immunoassay of Polycyclic Aromatic Hydrocarbons

    SciTech Connect

    Lin, Ying-Ying; Liu, Guodong; Wai, Chien M.; Lin, Yuehe

    2007-07-01

    A simple, rapid, and sensitive bioelectrochemical immunoassay method based on magnetic beads (MBs) has been developed to detect polycyclic aromatic hydrocarbons (PAHs). The principle of this bioassay is based on a direct competitive enzyme-linked immunosorbent assay using PAH-antibody-coated MBs and horseradish peroxidase (HRP)-labeled PAH (HRP-PAH). A magnetic process platform was used to mix and shake the samples during the immunoreactions and to separate free and unbound reagents after the liquid-phase competitive immunoreaction among PAH-antibody-coated MBs, PAH analyte, and HRP-PAH. After a complete immunoassay, the HRP tracers attached to MBs were transferred to a substrate solution containing 3, 3´, 5, 5´- tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2) for electrochemical detection. The voltammetric characteristics of the substrate were investigated, and the reduction peak current of TMB was used to quantify the concentration of PAH. The different parameters, including the amount of HRP-PAH conjugates, the enzyme catalytic reaction time, and the pH of the supporting electrolyte that governs the analytical performance of the immunoassay have been studied in detail and optimized. The detection limit of 50 pg mL-1 was obtained under optimum experimental conditions. The performance of this bioelectrochemical magnetic immunoassay was successfully evaluated with tap water spiked with PAHs, indicating that this convenient and sensitive technique offers great promise for decentralized environmental applications.

  3. AN EVALUATION OF FIVE COMMERCIAL IMMUNOASSAY DATA ANALYSIS SOFTWARE SYSTEMS

    EPA Science Inventory

    An evaluation of five commercial software systems used for immunoassay data analysis revealed numerous deficiencies. Often, the utility of statistical output was compromised by poor documentation. Several data sets were run through each system using a four-parameter calibration f...

  4. Enzyme linked immunoassay with stabilized polymer saccharide enzyme conjugates

    DOEpatents

    Callstrom, Matthew R. (Columbus, OH); Bednarski, Mark D. (Berkeley, CA); Gruber, Patrick R. (St. Paul, MN)

    1997-01-01

    An improvement in enzyme linked immunoassays is disclosed wherein the enzyme is in the form of a water soluble polymer saccharide conjugate which is stable in hostile environments. The conjugate comprises the enzyme which is linked to the polymer at multiple points through saccharide linker groups.

  5. Development of competitive immunoassays to hydroxyl containing fungicide metabolites

    Microsoft Academic Search

    Kevin C. Gough; Shila Jarvis; Ben C. Maddison

    2011-01-01

    This paper describes the isolation of monoclonal antibodies and the development of competitive immunoassays to pesticide metabolites of the fungicides imazalil, carbendazim and thiabendazole. The metabolite specific hydroxyl residues were used as the reactive group with which to link the metabolite to the carrier proteins Keyhole Limpet Haemocyanin (KLH) and Bovine Serum Albumin (BSA). In each case immune responses in

  6. Fluorescence quenching competitive immunoassay in micro droplets , Guomin Shan b

    E-print Network

    Hammock, Bruce D.

    in micro droplets was applied to the sensitive detection of the pyrethroid insecticide, esfenvalerate quenching effect that arises from the interaction between the protein and rhodamine molecules following effects and was shown to give rise to negligible interference with the immunoassay. # 2002 Elsevier

  7. Streamlining Immunoassays with Immiscible Filtrations Assisted by Surface Tension

    E-print Network

    Beebe, David J.

    are currently available including enzyme-linked immunosorbent assay (ELISA), radio- immunoassay (RIA of assay must be washed multiple times between each of these steps to ensure residual reagents (e is performed at the start of the assay (i.e., no pipetting steps are necessary during the assay). Analytes

  8. A Compact Immunoassay Platform Based on a Multicapillary Glass Plate

    PubMed Central

    Xue, Shuhua; Zeng, Hulie; Yang, Jianmin; Nakajima, Hizuru; Uchiyama, Katsumi

    2014-01-01

    A highly sensitive, rapid immunoassay performed in the multi-channels of a micro-well array consisting of a multicapillary glass plate (MCP) and a polydimethylsiloxane (PDMS) slide is described. The micro-dimensions and large surface area of the MCP permitted the diffusion distance to be decreased and the reaction efficiency to be increased. To confirm the concept of the method, human immunoglobulin A (h-IgA) was measured using both the proposed immunoassay system and the traditional 96-well plate method. The proposed method resulted in a 1/5-fold decrease of immunoassay time, and a 1/56-fold cut in reagent consumption with a 0.05 ng/mL of limit of detection (LOD) for IgA. The method was also applied to saliva samples obtained from healthy volunteers. The results correlated well to those obtained by the 96-well plate method. The method has the potential for use in disease diagnostic or on-site immunoassays. PMID:24859022

  9. Monitoring Pesticides and Personal Care Chemicals in Water by Immunoassay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the increasing number and quantity of organic pollutants, regulatory authorities require implementation of rapid, reliable, and cost-effective technologies for monitoring of water quality. Immunoassays provide a simple, powerful and inexpensive method for monitoring organic contaminants in bo...

  10. DETECTION OF NORWALK VIRUS IN STOOLS BY ENZYME IMMUNOASSAY

    EPA Science Inventory

    The development of a solid-phase microtiter enzyme immunoassay (EIA) for detection of Norwalk virus antigen in stool samples is described. The EIA was compared with a previously developed radioimmunoassay (RIA) for detection of Norwalk virus antigen in stools obtained from 30 vol...

  11. AUTOMATED FLOW FLUORESCENT IMMUNOASSAY FOR THE INSECTICIDE THIAMETHOXAM.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A sensitive automated flow fluorescent immunoassay was developed with KinExATM 3000 system for quantitative analysis of the neonicotinoid insecticide thiamethoxam, 3-(2-chlorothiaxol-5-ylmethyl)-5-methyl-4-nitroimino-1,3,5-oxadiazinane. A capillary flow cell contains antigen (thiamethoxam hapten-B...

  12. Kinase Activity Studied in Living Cells Using an Immunoassay

    ERIC Educational Resources Information Center

    Bavec, Aljos?a

    2014-01-01

    This laboratory exercise demonstrates the use of an immunoassay for studying kinase enzyme activity in living cells. The advantage over the classical method, in which students have to isolate the enzyme from cell material and measure its activity in vitro, is that enzyme activity is modulated and measured in living cells, providing a more…

  13. Microfluidic immunoassays as rapid saliva-based clinical diagnostics

    E-print Network

    Herr, Amy E.

    Microfluidic immunoassays as rapid saliva-based clinical diagnostics Amy E. Herr , Anson V. Hatch diagnostic that enables rapid quantitation of an oral disease biomarker in human saliva by using a monolithic facilitates hands-free saliva analysis by integrating sample pretreatment (filtering, enrichment, mixing

  14. Effect of phenolic compounds on immunoassays of peanut allergens.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phenolic compounds (PCs) are antioxidants. Because of their health benefit, PCs may be added to some food products. Occasionally, these products may be subjected to screening for food allergens (i.e. peanuts). In this case, the screening (an immunoassay technique) may or may not be affected by the P...

  15. DEVELOPMENT OF SENSITIVE MAGNETIC PARTICLE IMMUNOASSAY FOR POLYBROMINATED DIPHENYL ETHERS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A sensitive magnetic particle based immunoassay for polybrominated diphenyl ether (PBDE) was developed. Rabbit antiserum was produced by immunizing the rabbit with 4-(2,4-dibromo-5-(2,4-dibromophenoxy)phenoxy)butyrate-BSA. The PBDE ligand and horse radish peroxidase were conjugated via NHS and EDA...

  16. A rapid diffusion immunoassay in a T-sensor

    Microsoft Academic Search

    Anson Hatch; Andrew Evan Kamholz; Kenneth R. Hawkins; Matthew S. Munson; Eric A. Schilling; Bernhard H. Weigl; Paul Yager

    2001-01-01

    We have developed a rapid diffusion immunoassay that allows measurement of small molecules down to subnanomolar concentrations in <1 min. This competitive assay is based on measuring the distribution of a labeled probe molecule after it diffuses for a short time from one region into another region containing antigen-specific antibodies. The assay was demonstrated in the T-sensor, a simple microfluidic

  17. Detection of petroleum hydrocarbons in soil and water by immunoassay

    SciTech Connect

    Selisker, M.Y.; McCaffrey, C.R.; Herzog, D.P.; Itak, J.A. [Ohmicron Corp., Newtown, PA (United States)

    1995-12-31

    A magnetic particle based enzyme immunoassay (EIA) that detects small aromatic hydrocarbons was developed. This EIA can be used to directly test water samples or can be coupled with a simple extraction method to identify the presence of petroleum hydrocarbons in soil. This immunoassay offers several advantages over traditional testing methods (i.e. GC) including speed, cost effectiveness and portability. This assay can be performed on site in less than one hour. The assay`s performance with soil and water samples was evaluated in several studies. In one study conducted on water samples from locations across the US, recoveries of spiked Total BTEX averaged greater than 99% with results ranging from 87% to 119%; one false positive (1.8%) was observed. Soil samples spiked with Total BTEX at concentrations ranging from 0.25 to 10 ppm were extracted, diluted and evaluated in the immunoassay. Recoveries averaged 113% with results ranging from 104% to 120%. In a third study, soil samples collected from various remediation sites were extracted and run in the immunoassay. The assay and recommended extraction procedure agreed well with results obtained by EPA Method 8020 in determining the presence and degree of contamination. Additional study results and data on the cross-reactivity of the assay for various small aromatic hydrocarbons and petroleum fuel mixtures (i.e. gasoline) are also presented.

  18. EVALUATION OF FIVE COMMERCIAL IMMUNOASSAY DATA ANALYSIS SOFTWARE SYSTEMS

    EPA Science Inventory

    The U.S. EPA, Office of Research and Development, conducted an evaluation of five commercial software systems used for immunoassay data analysis. he evaluation revealed numerous deficiencies. often, the utility of statistical output was compromised by poor documentation. everal d...

  19. Protein Microchips: Use for Immunoassay and Enzymatic Reactions

    Microsoft Academic Search

    Pavel Arenkov; Alexander Kukhtin; Anne Gemmell; Sergey Voloshchuk; Valentina Chupeeva; Andrei Mirzabekov

    2000-01-01

    Different proteins such as antibodies, antigens, and enzymes were immobilized within the 100 × 100 × 20-?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

  20. Donor Hemovigilance during Preparatory Plasmapheresis

    PubMed Central

    Diekamp, Ulrich; Gneißl, Johannes; Rabe, Angela; Kießig, Stephan T.

    2014-01-01

    Summary Background Reports on unexpected donor events (UEs) during preparatory plasmapheresis (PPP) are scarce, and rarely consider technical UEs. Methods Defined local and systemic UEs were graded by severity; technical UEs were not graded. On January 1, 2008, E.B.P.S.-Logistics (EBPS) installed the UE module for plasma management software (PMS). Donor room physicians entered UEs daily into the PMS. Medical directors reviewed entries quarterly. EBPS compiled data on donors, donations and UEs from January 1, 2008 to June 30, 2011. Results 66,822 UEs were observed during 1,107,846 PPPs for a corrected incidence of 6.55% (1.4% local, 0.55% systemic, 4.6% technical UEs). 3.36% of PPPs were accompanied by 1 UE and 1.18% by >1 UE (2-5). 13.7% of donors undergoing PPP for the first time, 9.7% of those having a second PPP and 4.0% of those having a third or more PPPs were associated with UEs. Most common UEs were repeated venipuncture, and broken-off collection due to venous access problems and small hematomas. Severe systemic UEs occurred at a rate of 36 per 100,000 PPPs. Conclusions Technical UEs were common with PPP. UEs accompanied first and second donations significantly more frequently than for subsequent donations. PMID:24847188

  1. Anonymous Donor Dr. Sara Abosch

    E-print Network

    Dasgupta, Dipankar

    Anonymous Donor Dr. Sara Abosch ACRE Dr. Rob and Brenda Adams Dr. Richmond B. Adams Alchemy Aldo and Lynette Black Blind Bear Bluff City Coffee Dr. Mark E. Bradshaw Dr. Peter J. Brand Dr. Linde M. Brocato Ciao Bella Dr. Robert Cohen Dr. John T. Cooper Dr. William G. Crump Mr. Kelly O. Davis Dr. Pamela R

  2. Early diagnosis of typhoid fever by an enzyme immunoassay using Salmonella typhi outer membrane protein preparations.

    PubMed

    Verdugo-Rodríguez, A; López-Vidal, Y; Puente, J L; Ruíz-Placios, G M; Calva, E

    1993-04-01

    An enzyme immunoassay (EIA) for detection of serum antibodies in patients with typhoid fever was developed using Salmonella typhi outer membrane protein (OMP) preparations as antigen. Acute phase (first week) sera from adult typhoid fever patients were tested as well as sera from the following control groups: adult travellers with diarrhea caused by enterotoxigenic Escherichia coli, children infected with Campylobacter jejuni, healthy Mexican adult blood donors, and adults with septicemia caused by other organisms. At a 1:3,125 serum dilution, the mean absorbance values were 1.41 in the typhoid fever patients, and 0.57, 0.55, 0.51 and 0.52 in the respective control groups. Inhibition EIA studies using OMP preparations or lipopolysaccharide (LPS) as free antigen indicated that proteins can play an important role in the detection of antibodies in early typhoid fever. This EIA may be useful for the diagnosis of typhoid fever since results were obtained within about five hours and in an endemic area antibodies against Salmonella typhi OMP preparations appear early in the course of the disease. PMID:8513812

  3. Introducing novel amorphous carbon nanoparticles as energy acceptors into a chemiluminescence resonance energy transfer immunoassay system.

    PubMed

    Wang, Zhenxing; Gao, Hongfei; Fu, Zhifeng

    2013-11-21

    A novel chemiluminescence resonance energy transfer (CRET) system for competitive immunoassay of biomolecules was developed by using novel amorphous carbon nanoparticles (CNPs) prepared from candle soot as energy acceptors. The CNPs were firstly prepared to bind with the antigen (Ag) for obtaining the nanocomposite CNP-Ag, and this obtained CNP-Ag was then reacted with the horseradish peroxidase-labeled antibody (HRP-Ab) to assemble the CRET system. The luminol catalyzed by HRP serving as the energy donor for CNPs triggered the CRET phenomenon between luminol and CNPs, which led to the chemiluminescence signal decrease. Due to the competitive immunoreaction of the target antigen and the CNP-Ag, a part of the CNP-Ag was replaced from the HRP-Ab, and then resulted in a weaker interaction between luminol and CNPs. Thus the competitive immunoreaction led to a higher chemiluminescence emission. This CNP-based CRET system was successfully applied to detect the human IgG as a model analyte, and a linear range of 10-200 ng mL(-1) and a detection limit of 1.9 ng mL(-1) (S/N = 3) were obtained. The results for real sample analysis demonstrated its application potential in some important areas such as clinical diagnosis. PMID:23979821

  4. Development of an immunoassay to detect benzene adducts in hemoglobin

    SciTech Connect

    Grassman, J.A.

    1993-01-01

    The purpose of this project was to develop an immunoassay to detect the adducts formed in hemoglobin after exposure to benzene, which is known to cause bone marrow degeneration and acute myelogenous leukemia. The use of benzene-adduct detection as a biological monitoring method would permit measurement of low exposures and exposures sustained weeks earlier. The reactivity of hydroquinone, an important benzene metabolite, with blood proteins and amino acids was investigated in order to decide which antigens and analytes were likely to be suitable for immunoassay development. The second section determined the combination of benzene-metabolite and antigen need to produce an immunoassay with the requisite low detection limit and specificity. The immunoassays with the best performance were tested on hemoglobin from benzene-exposed mice. In vitro studies showed that hydroquinone efficiently formed adducts with erythrocyte membranes and hemoglobin but not with albumin. Adduction efficiency was greater in incubations using purified hemoglobin than whole blood. Cysteine accounted for 15 to 27% of the adducts formed by hydroquinone. The site of the other adducts were not identified although there was evidence that the hemoglobin heme was adducted. Adducts were found on only 1 of the 2 globin chains. Tryptic digestion of the globin failed to associate the adducts with a specific peptide. Antigens made from hydroquinone-adducted hemoglobin but not hydroquinone-adducted cysteines coupled to carrier proteins effectively elicited adduct-specific antibodies. Interference due to reactivity to hemoglobin was controlled by using uniform quantities of hemoglobin in all wells. The mid-range of the best assays were approximately 12 pmoles HQ per well. Antibodies directed toward hemoglobin adducted with the benzene metabolites phenol, catechol and 1,2,4-trihydroxybenzene were also made. The performance of the anti-1,2,4-trihydroxybenzene were suitable for quantitative immunoassays.

  5. [Psychosomatic aspects of living donor liver transplantation].

    PubMed

    Erim, Y; Beckmann, M; Gerken, G; Paul, A; Senf, W; Beckebaum, S

    2010-09-01

    Living donor liver transplantation (LDLT) offers the option to reduce organ scarcity and thereby waiting list mortality. The crucial ethical problem of LDLT is the fact that the well being of a donor is being jeopardized for the improvement of quality of life of the recipient. To preserve mental health of the donors, psychosomatic evaluation should be conducted including examination of the coping capacity, the mental stability of the donor and the voluntary nature of the donation. Thus a comprehensive disclosure of information to donors is necessary. Realistic outcome expectations, family relationships without extreme conflicts, sufficient autonomy of the donor-recipient relationship and social and familiar support are predictors facilitating a favorable psychosocial outcome for the donor. Before and after LDLT the health-related quality of life of the donors is similar or increased in comparison to the general population. Psychiatric complications following LDLT can occur in 13% of the donors. Female donors, donors who have surgical complications themselves and donors with unrealistic outcome expectations should be given psychotherapeutic support before they are admitted to living liver donation. Urgent indications in the case of acute liver failure and the donation by adult children for their parents are particular stress factors. For the safety of the donor, these combinations should be avoided whenever possible. PMID:20730409

  6. Becoming a Blood Stem Cell Donor

    MedlinePLUS

    ... total__ Find out why Close Becoming a Blood Stem Cell Donor NCIcancertopics Subscribe Subscribed Unsubscribe 319 Subscription preferences ... Ever considered becoming a bone marrow or blood stem cell donor? Follow this true story of a former ...

  7. Monetary Compensation and Blood Donor Return: Results of a Donor Survey in Southwest Germany

    PubMed Central

    Weidmann, Christian; Schneider, Sven; Weck, Eberhard; Menzel, Dagmar; Klüter, Harald; Müller-Steinhardt, Michael

    2014-01-01

    Summary Background/Aims The aim of this study was to compare donor return patterns of non-compensated and compensated German first-time donors to assess the effect of monetary reward on donor return. Methods We conducted a retrospective analysis of a donor survey of 3,077 non-compensated and 738 compensated German first-time donors. Survey data were pooled and linked with blood donor return rates within the 1st, 2nd, and 3rd year. Logistic regression models were used to estimate differences in the probability of donor return between non-compensated and compensated donors. Results In the first 2 years following the initial donation, compensated donors were more likely to return with the odds of giving at least one further donation 1.86 (1st year) and 1.32 (2nd year) times higher for compensated donors than for non-compensated donors. In the 3rd year, there were no significant differences in donor return. Conclusion This report, which was based on two non-randomized donor samples, suggests that monetary compensation may increase the likelihood of donors returning in the first months after the initial donation. Monetary reward may therefore be used as a short-term strategy to recruit new donors. The long-term commitment, however, seems not to be affected by monetary reward, and complementary donor retention strategies are needed. PMID:25254021

  8. DGTI Register of Rare Donors

    PubMed Central

    Hustinx, Hein

    2014-01-01

    Summary For patients with antibodies against the most common blood groups a rapid and efficient supply of compatible erythrocyte concentrates is self-evident. But typically we have to make the greatest effort providing blood for these patients, which have made antibodies against common blood groups. There are however patients with antibodies against rare blood group antigens that need special blood. The supply of such blood can be very difficult and mostly time-consuming. For this reason we set up a database of blood donors with rare blood groups. Since 2005 the BTS SRC Berne Ltd. has run this database on behalf of the Swiss BTS SRC. After a reorganization and extension of the database, conducted during 2011/2012, the data file was renamed ‘DGTI Register of Rare Donors’ and is now run under the patronage of the German Society for Transfusion Medicine and Immunohematology (DGTI). PMID:25538534

  9. Changing Pattern of Donor Selection Criteria in Deceased Donor Liver Transplant: A Review of Literature

    PubMed Central

    Routh, Dronacharya; Naidu, Sudeep; Sharma, Sanjay; Ranjan, Priya; Godara, Rajesh

    2013-01-01

    During the last couple of decades, with standardization and progress in surgical techniques, immunosuppression and post liver transplantation patient care, the outcome of liver transplantation has been optimized. However, the principal limitation of transplantation remains access to an allograft. The number of patients who could derive benefit from liver transplantation markedly exceeds the number of available deceased donors. The large gap between the growing list of patients waiting for liver transplantation and the scarcity of donor organs has fueled efforts to maximize existing donor pool and identify new avenues. This article reviews the changing pattern of donor for liver transplantation using grafts from extended criteria donors (elderly donors, steatotic donors, donors with malignancies, donors with viral hepatitis), donation after cardiac death, use of partial grafts (split liver grafts) and other suboptimal donors (hypernatremia, infections, hypotension and inotropic support).

  10. Changing pattern of donor selection criteria in deceased donor liver transplant: a review of literature.

    PubMed

    Routh, Dronacharya; Naidu, Sudeep; Sharma, Sanjay; Ranjan, Priya; Godara, Rajesh

    2013-12-01

    During the last couple of decades, with standardization and progress in surgical techniques, immunosuppression and post liver transplantation patient care, the outcome of liver transplantation has been optimized. However, the principal limitation of transplantation remains access to an allograft. The number of patients who could derive benefit from liver transplantation markedly exceeds the number of available deceased donors. The large gap between the growing list of patients waiting for liver transplantation and the scarcity of donor organs has fueled efforts to maximize existing donor pool and identify new avenues. This article reviews the changing pattern of donor for liver transplantation using grafts from extended criteria donors (elderly donors, steatotic donors, donors with malignancies, donors with viral hepatitis), donation after cardiac death, use of partial grafts (split liver grafts) and other suboptimal donors (hypernatremia, infections, hypotension and inotropic support). PMID:25755521

  11. Fluorescence polarization immunoassays for the quantification of caffeine in beverages.

    PubMed

    Oberleitner, Lidia; Grandke, Julia; Mallwitz, Frank; Resch-Genger, Ute; Garbe, Leif-Alexander; Schneider, Rudolf J

    2014-03-19

    Homogeneous fluorescence polarization immunoassays (FPIAs) were developed and compared for the determination of caffeine in beverages and cosmetics. FPIAs were performed in cuvettes in a spectrometer for kinetic FP measurements as well as in microtiter plates (MTPs) on a multimode reader. Both FPIAs showed measurement ranges in the ?g/L range and were performed within 2 and 20 min, respectively. For the application on real samples, high coefficients of variations (CVs) were observed for the performance in MTPs; the CVs for FPIAs in cuvettes were below 4%. The correlations between this method and reference methods were satisfying. The sensitivity was sufficient for all tested samples including decaffeinated coffee without preconcentration steps. The FPIA in cuvettes allows a fast, precise, and automated quantitative analysis of caffeine in consumer products, whereas FPIAs in MTPs are suitable for semiquantitative high-throughput screenings. Moreover, specific quality criteria for heterogeneous assays were applied to homogeneous immunoassays. PMID:24597592

  12. Field screening for aldrin in soil by immunoassay

    SciTech Connect

    McCain, R.G.; Myers, M.L.

    1994-08-01

    A number of 5-gal cans labeled {open_quotes}aldrin{close_quotes} were found dumped in an isolated area near the boundary of the Hanford Site. Initial laboratory analysis showed high concentrations of aldrin in the soil directly beneath the cans. The site was included in an expedited response action (ERA) undertaken to clean up a large area along the western margin of the Hanford Site. A commercially available immunoassay test kit was modified to screen for aldrin in soil at an action level of 2 mg/kg. Field tests carried out as the contaminated soil was removed showed that the contamination extended significantly deeper than originally anticipated. The field immunoassay provided the cleanup crew with rapid turnaround results, which were used to guide the cleanup activity.

  13. The challenge of improving donor heart preservation.

    PubMed

    McCrystal, Graham D; Pepe, Salvatore; Esmore, Donald S; Rosenfeldt, Franklin L

    2004-03-01

    Heart transplantation has in recent years become the treatment of choice for end stage heart failure. However while the waiting list for transplantation is growing steadily, the donor pool is not increasing. Therefore, in order to meet demand, transplant programs are using older, "marginal donors" and accepting longer ischaemic times for their donor hearts. As donor organs are injured as a consequence of brain death, during the period of donor management, at organ harvest, preservation, implantation and reperfusion, expansion of acceptance criteria places a great burden on achieving optimal long-term outcomes. However, at each step in the process of transplantation strategies can be employed to reduce the injury suffered by the donor organs. In this review, we set out what steps can be taken to improve the quality of donor organs. PMID:16352173

  14. FLUORESCENCE POLARIZATION IMMUNOASSAY FOR THE INSECTICIDE DDT AND ITS METABOLITES

    Microsoft Academic Search

    S. A. Eremin; A. E. Bochkareva; V. A. Popova; A. Abad; J. J. Manclus; J. V. Mercader; A. Montoya

    2002-01-01

    Two fluorescence polarization immunoassays (FPIA) for detection of the insecticide DDT (DDT-specific FPIA) and the sum of DDT isomers and metabolites (DDT class-specific FPIA) were developed. Various fluorescein-labeled tracers were synthesized and studied in order to achieve a high sensitivity using different monoclonal antibodies. For DDT-specific assay the sensitivity, estimated as limit of detection, was 12 ng\\/mL, with a linear working

  15. Determination of chloramphenicol in milk by a fluorescence polarization immunoassay

    Microsoft Academic Search

    N. V. Gasilova; S. A. Eremin

    2010-01-01

    A procedure for the determination of the drug chloramphenicol using a fluorescence polarization immunoassay (FPIA) was proposed.\\u000a The optimum pairs of antibodies and antigens labeled with fluorescein were chosen, and the analytical characteristics of the\\u000a procedure were determined. A rapid procedure for milk sample preparation with the use of a saturated solution of ammonium\\u000a sulfate was optimized. The total time

  16. Development of One-Step Fluorescence Polarization Immunoassay for Progesterone

    Microsoft Academic Search

    Ji Youn Hong; Myung Ja Choi

    2002-01-01

    A one-step fluorescence polarization immunoassay (FPIA) was developed to measure progesterone level using an immunocomplex single reagent (SR), a preequilibrated mixture of antibody and tracer. Several fluores- cence-labeled progesterone tracers were synthesized using the combination of two progesterone derivatives, 11a a- hemisuccinyloxyprogesterone (P-11HS) and progesterone-3-(O-carboxymethyl)oxime (P-3CMO), and three fluo- rescence labels, fluoresceinamine isomer I and II, and ethylenediamine fluoresceinthiocarbamyl (EDF).

  17. Enzyme immunoassay validation detection of cocaine in for qualitative sweat

    Microsoft Academic Search

    VINA SPIEHL ER; JOHN FAY; ROBERT FOGERSON; DON SCHOENDORFER; R. SAM NIEDBALA

    A solid-phase enzyme immunoassay (EIA) involving micro- titer plates was modified for analysis of cocaine in sweat. Sweat was collected with the PharmChek?' sweat patch and drugs were eluted from the collection pad of the patch. The sweat contained primarily parent cocaine. The assay was determined to have cross-reactivity for cocaine of 102% relative to 100% for the benzoylecgonine (BE)

  18. A device architecture for three-dimensional, patterned paper immunoassays.

    PubMed

    Schonhorn, Jeremy E; Fernandes, Syrena C; Rajaratnam, Anjali; Deraney, Rachel N; Rolland, Jason P; Mace, Charles R

    2014-12-21

    Diagnostic assays can provide valuable information about the health status of a patient, which include detection of biomarkers that indicate the presence of an infection, the progression or regression of a disease, and the efficacy of a course of treatment. Critical healthcare decisions must often be made at the point-of-care, far from the infrastructure and diagnostic capabilities of centralized laboratories. There exists an obvious need for diagnostic tools that are designed to address the unique challenges encountered by healthcare workers in limited-resource settings. Paper, a readily-available and inexpensive commodity, is an attractive medium with which to develop diagnostic assays for use in limited-resource settings. In this article, we describe a device architecture to perform immunoassays in patterned paper. These paper-based devices use a combination of lateral and vertical flow to control the wicking of fluid in three-dimensions. We provide guidelines to aid in the design of these devices and we illustrate how patterning can be used to tune the duration and performance of the assay. We demonstrate the use of these paper-based devices by developing a sandwich immunoassay for human chorionic gonadotropin (hCG) in urine, a biomarker of pregnancy. We then directly compare the qualitative and quantitative results of these paper-based immunoassays to commercially available lateral flow tests (i.e., the home pregnancy test). Our results suggest paper-based devices may find broad utility in the development of immunoassays for use at the point-of-care. PMID:25300302

  19. PCB detection by immunoassay -- A wipe test for surface contamination

    SciTech Connect

    Dautlick, J.X.; Teaney, G.B.; Hudak, R.T.; Melby, J.M. [Strategic Diagnostics Industries Inc., Newark, DE (United States)

    1995-12-31

    Immunoassay based field screening methods are gaining acceptance by the environmental diagnostics industry for on-site characterization and remediation monitoring. Polychlorinated biphenyls (PCBs), a family of molecules classified as potential carcinogens, can be easily detected on-site by immunoassay screening methods. This results in reduced project cost and improved onsite efficiency, since field screening immunoassays short cut the long turn around time of laboratory analysis while providing reliable results. On site wipe test technology for assessing PCB contamination on surfaces such as walls and floors of PCB storage facilities has been developed to supplement the D TECH{trademark} PCB soil assay. This sampling technique can also be used to monitor for transformer leaks, spills and to evaluate equipment decontamination processes. The D TECH PCB wipe test is quick, cost effective, highly specific and user friendly. The surface is sampled by wiping a 100 cm{sup 2} area with a 1 cm{sup 2} pad saturated with an extractant. The PCB is extracted from the sampling pad during a short extraction step. The sample is filtered, diluted, and run in the D TECH PCB field screening system. The components of the immunoassay include PCB specific antibodies (Ab) covalently linked to small latex particles, a PCB analog which is covalently linked to alkaline phosphatase, and the free PCB from the sample. The free PCB competes with the enzyme linked analog for the Ab binding sites. The latex particles are then collected on a filter device, washed, and an enzyme substrate is added. The amount of color produced is inversely proportional to the concentration of free PCB on the sample, and can be determined using a hand held reflectometer, or a color card.

  20. Analytical validation of anti-toxoplasma IgG immunoassays.

    PubMed

    Souza, Guenael Freire de; Carvalho, Darlene; Pedrosa, William; Franck, Jacqueline; Piarroux, Renaud

    2012-01-01

    There are often discrepancies when using different methods to measure anti-Toxoplasma gondii IgG levels in patient samples. The diagnostic performance of a chemiluminescent immunoassay (CLIA) and an enzyme-linked fluorescent assay (ELFA) used as confirmatory tests for samples identified as positive or equivocal by an electrochemiluminescent immunoassay (ECLIA) were examined. Cut-off values were those stated by the manufacturer, and Western blot was used to confirm the results of all methods. All samples identified as positive by ECLIA (n=93) were confirmed as positive by Western blot, as were 14 of the 28 samples identified as equivocal. When these 121 samples were retested, the sensitivities of CLIA and ELFA were 64.4% and 73.8%, respectively. Both methods exhibited a specificity of 100%. This study confirms that the results obtained from the different immunoassays are not comparable, and neither CLIA nor ELFA should be used to confirm ECLIA results, which should instead be confirmed by methods such as Western blot or Sabin-Feldman dye test. PMID:23141993

  1. Enhancing immunoassay possibilities using magnetic carriers in biological fluids

    NASA Astrophysics Data System (ADS)

    Yu, Hao

    1997-05-01

    An antibody-based magnetic plate chemifluorescent immunoassay (MPFIA) for effective and rapid detection of bacteria and toxoid from biological fluids was developed. Streptavidin (SA)- magnetic particles and biotinylated antibody as a solid phase immunomagnetic carrier was used for antigen capture. An alkaline phosphatase-antibody conjugate as a secondary capture antibody to the antigen forms a sandwich with the primary antibody. The fluorgenic substrate, AttoPhos reacts with alkaline phosphatase that emits chemifluorescent intensities are proportional to captured antigens. Antigen separation and concentration from biological fluids using immunomagnetic carrier are the key step to reduce media interference for sensitive detection. Results of these efforts may actually enhance the immunoassay possibilities by concentration of specific antigen and reduction of background noise. Magnetic separation and chemifluorescent detection have been achieved by a multiple-well formatted magnetic plate separator and a fluorescent plate detector, respectively. Experiments were performed for virulent Escherichia coli cells, Staphylococcal enterotoxin B toxoid and Bacillus subtilus spore detection in biological fluids. In general, the fluorescent detection can be achieved at the same sensitivities as enzyme-linked immunoassay and the ECL detection is more sensitive than fluorescent assay. However, the unique features of MPFIA and MPECL are that the biological samples can be rapidly processed and detected on the same multiple sample formatted plate within one hour assay time.

  2. Multiplexed electrochemical immunoassay of biomarkers using chitosan nanocomposites.

    PubMed

    Chen, Xia; Ma, Zhanfang

    2014-05-15

    In this work, a novel and sensitive multiplexed immunoassay protocol for simultaneous electrochemical determination of alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA) was designed using functionalized chitosan composites. The immunosensing platform was prepared via immobilizing capture anti-AFP and anti-CEA on chitosan-Au nanoparticles (AuNPs) through EDC/NHS linking. The signal tags were fabricated by immobilizing electroactive redox probes - Prussian blue (PB) and ferrocenecarboxylic acid (Fc) on chitosan (CHIT), following by absorbing AuNPs to immobilize labeled anti-AFP and anti-CEA, respectively. A sandwich-type immunoassay format was employed for the simultaneous detection of AFP and CEA. The assay was based on the electrochemical oxidation/reduction of the redox species in signal tags, which has a relationship with the concentration of analytes. Experimental results revealed that the multiplexed electrochemical immunoassay enabled the simultaneous monitoring of AFP and CEA with a wide range of 0.05-100 ng mL(-1) for both AFP and CEA. The detection limits (LOD) was 0.03 ng mL(-1) for AFP and 0.02 ng mL(-1) for CEA (S/N=3). The assay results of serum samples with the proposed method were in a good agreement with the reference values from standard ELISA method. And the negligible cross-reactivity between the two analytes makes it possesses potential promise in clinical diagnosis. PMID:24413402

  3. Heterogeneous Immunoassays Using Magnetic beads On a Digital Microfluidic Platform

    PubMed Central

    Sista, Ramakrishna S.; Eckhardt, Allen E.; Srinivasan, Vijay; Pollack, Michael G.; Palanki, Srinivas; Pamula, Vamsee K.

    2009-01-01

    A digital microfluidic platform for performing heterogeneous sandwich immunoassays based on efficient handling of magnetic beads is presented in this paper. This approach is based on manipulation of discrete droplets of samples and reagents using electrowetting without the need for channels where the droplets are free to move laterally. Droplet-based manipulation of magnetic beads therefore does not suffer from clogging of channels. Immunoassays on a digital microfluidic platform require the following basic operations: bead attraction, bead washing, bead retention, and bead resuspension. Several parameters such as magnetic field strength, pull force, position, and buffer composition were studied for effective bead operations. Dilution-based washing of magnetic beads was demonstrated by immobilizing the magnetic beads using a permanent magnet and splitting the excess supernatant using electrowetting. Almost 100% bead retention was achieved after 7776 fold dilution-based washing of the supernatant. Efficient resuspension of magnetic beads was achieved by transporting a droplet with magnetic beads across five electrodes on the platform and exploiting the flow patterns within the droplet to resuspend the beads. All the magnetic-bead droplet operations were integrated together to generate standard curves for sandwich heterogeneous immunoassays on Human Insulin and Interleukin-6 (IL-6) with a total time to result of seven minutes for each assay. PMID:19023486

  4. History of inductively coupled plasma mass spectrometry-based immunoassays

    NASA Astrophysics Data System (ADS)

    Giesen, Charlotte; Waentig, Larissa; Panne, Ulrich; Jakubowski, Norbert

    2012-10-01

    The analysis of biomolecules requires highly sensitive and selective detection methods capable of tolerating a complex, biological matrix. First applications of biomolecule detection by ICP-MS relied on the use of heteroelements as a label for quantification. However, the combination of immunoassays and ICP-MS facilitates multiparametric analyses through elemental tagging, and provides a powerful alternative to common bioanalytical methods. This approach extends the detection of biomarkers in clinical diagnosis, and has the potential to provide a deeper understanding of the investigated biological system. The results might lead to the detection of diseases at an early stage, or guide treatment plans. Immunoassays are well accepted and established for diagnostic purposes, albeit ICP-MS is scarcely applied for the detection of immune-based assays. However, the screening of biomarkers demands high throughput and multiplex/multiparametric techniques, considering the variety of analytes to be queried. Finally, quantitative information on the expression level of biomarkers is highly desirable to identify abnormalities in a given organism. Thus, it is the aim of this review to introduce the fundamentals, and to discuss the enormous strength of ICP-MS for the detection of different immunoassays on the basis of selected applications, with a special focus on LA-ICP-MS.

  5. Multiplex Electrochemical Immunoassay Using Gold Nanoparticle Probes and Immunochromatographic Strips

    SciTech Connect

    Mao, Xun; Baloda, Meenu; Gurung, Anant; Lin, Yuehe; Liu, Guodong

    2008-10-20

    We describe a multiplex electrochemical immunoassay based on the use of gold nanoparticle (Au-NP) probes and immunochromatographic strips (ISs). The approach takes advantage of the speed and low cost of the conventional IS tests and the high sensitivities of the nanoparticle-based electrochemical immunoassays. Rabbit IgG(R-IgG) and human IgM (H-IgM) were used as model targets for the demonstration of the proof of concept. The Au-NPs based sandwich immunoreactions were performed on the IS, and the captured gold nanoparticle labels on the test zones were determined by highly-sensitive stripping voltammetric measurement of the dissolved gold ions (III) with a carbon paste electrode. The detection limits are 1.0 and 1.5 ng/mL with the linear ranges of 2.5-250 ng/mL for quantitative detection of R-IgG and H-IgM, respectively. The total assay time is around 25 minutes. Such multiplex electrochemical immunoassay could be readily highly multiplexed to allow simultaneous parallel detection of numerous proteins and is expected to open new opportunities for protein diagnostics and biosecurity.

  6. Superfund Innovative Technology Evaluation (SITE) report for the Westinghouse Bio-Analytic Systems pentachlorophenol (PCPpcp) immunoassays

    SciTech Connect

    Silverstein, M.E.; White, R.J.; Gerlach, R.W.; Van Emon, J.M.

    1992-05-01

    The results of the demonstration of two Westinghouse Bio-Analytic Systems (WBAS) immunoassay technologies are described in the report. The immunoassays measure parts per billion concentrations of pentachlorophenol in environmental water samples. The study was conducted under the Superfund innovative Technology Evaluation (SITE) Program and designed to evaluate the ruggedness and utility of a semiquantitative immunoassay field kit. Results obtained from the field kit were compared to those obtained from a quantitative, high-sample-capacity plate immunoassay. The results of the WBAS immunoassay demonstration support the conclusion that the field immunoassay is a useful screening tool. The demonstration verified that the method can provide qualitative or semiquantitative screening information. Although the results were more variable than had been anticipated, the incorporation of additional procedural precautions and carefully chosen quality control acceptance criteria for on-site analysis could improve performance substantially. Both immunoassays produced results biased high compared to the GC/MS results, but the tendency was not large and may have been partly due to loss during sample extraction (EPA Method 3510) prior to analysis by gas chromatography/mass spectrometry. The detection of structurally related compounds by the immunoassays may have also contributed to the high bias. The results indicate that the plate immunoassay is an accurate and precise method for quantitating pentachlorophenol in water.

  7. Gamete donors' expectations and experiences of contact with their donor offspring

    PubMed Central

    Kirkman, Maggie; Bourne, Kate; Fisher, Jane; Johnson, Louise; Hammarberg, Karin

    2014-01-01

    STUDY QUESTION What are the expectations and experiences of anonymous gamete donors about contact with their donor offspring? SUMMARY ANSWER Rather than consistently wanting to remain distant from their donor offspring, donors' expectations and experiences of contact with donor offspring ranged from none to a close personal relationship. WHAT IS KNOWN ALREADY Donor conception is part of assisted reproduction in many countries, but little is known about its continuing influence on gamete donors' lives. STUDY DESIGN, SIZE, DURATION A qualitative research model appropriate for understanding participants' views was employed; semi-structured interviews were conducted during January–March 2013. PARTICIPANTS/MATERIALS, SETTING, METHODS Before 1998, gamete donors in Victoria, Australia, were subject to evolving legislation that allowed them to remain anonymous or (from 1988) to consent to the release of identifying information. An opportunity to increase knowledge of donors' expectations and experiences of contact with their donor offspring recently arose in Victoria when a recommendation was made to introduce mandatory identification of donors on request from their donor offspring, with retrospective effect. Pre-1998 donors were invited through an advertising campaign to be interviewed about their views, experiences and expectations; 36 sperm donors and 6 egg donors participated. MAIN RESULTS AND THE ROLE OF CHANCE This research is unusual in achieving participation by donors who would not normally identify themselves to researchers or government inquiries. Qualitative thematic analysis revealed that most donors did not characterize themselves as parents of their donor offspring. Donors' expectations and experiences of contact with donor offspring ranged from none to a close personal relationship. LIMITATIONS, REASONS FOR CAUTION It is not possible to establish whether participants were representative of all pre-1998 donors. WIDER IMPLICATIONS OF THE FINDINGS Anonymous donors' needs and desires are not homogeneous; policy and practice should be sensitive and responsive to a wide range of circumstances and preferences. Decisions made to restrict or facilitate contact or the exchange of information have ramifications for donors as well as for donor-conceived people. STUDY FUNDING/COMPETING INTEREST(S) The study was funded by the Victorian Department of Health. The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER Not applicable. PMID:24549216

  8. Microchip device with 64-site electrode array for multiplexed immunoassay of cell surface antigens based on electrochemiluminescence resonance energy transfer.

    PubMed

    Wu, Mei-Sheng; Shi, Hai-Wei; He, Li-Jing; Xu, Jing-Juan; Chen, Hong-Yuan

    2012-05-01

    This paper describes a novel on-chip microarray platform based on an electrochemiluminescence resonance energy transfer (ECL-RET) strategy for rapid assay of cancer cell surface biomarkers. This platform consists of 64 antigen-decorated CdS nanorod spots with the diameter of 1.0 cm uniformly distributed on 16 indium tin oxide (ITO) strips, which is coated with a multichannel decorated polydimethylsiloxane (PDMS) slice to realize multiplexed determination of antigens. To shorten the immune reaction time in the microchannels and simplify the device, magnetic stirring and four-channel universal serial bus (USB) ports for plug-and-play were used. When Ru(bpy)(3)(2+) labeled antibodies were selectively captured by the corresponding antigens on the CdS nanorod spot array, ECL-RET from the CdS nanorod (donor) by cathodic emission in the presence of K(2)S(2)O(8) to Ru(bpy)(3)(2+) (acceptor) occurred. With signal amplification of Ru(bpy)(3)(2+) and competitive immunoassay, carcinoembryonic antigen (CEA), ?-fetoprotein (AFP), and prostate specific antigen (PSA) as models were detected on this microfluidic device via recording the increased ECL-RET signals on electrode surfaces. Furthermore, this multiplexed competitive immunoassay was successfully used for detecting cancer cell surface antigens via the specific antibody-cell interactions and cell counting via cell surface receptors and antigens on the CdS nanorod surface. This platform provides a rapid and simple but sensitive approach with microliter-level sample volume and holds great promise for multiplexed detection of antigens and antigen-specific cells. PMID:22494075

  9. Miniaturization of a homogeneous fluorescence immunoassay based on energy transfer using nanotiter plates as high-density sample carriers.

    PubMed

    Schobel, U; Coille, I; Brecht, A; Steinwand, G M; Gauglitz, G

    2001-11-01

    The miniaturization of a homogeneous competitive immunoassay to a final assay volume of 70 nL is described. As the sample carrier, disposable plastic nanotiter plates (NTP) with dimensions of 2 x 2 cm2 containing 25 x 25 wells, corresponding to approximately 15,000 wells on a traditional 96-well microtiter plate footprint, were used. Sample handling was accomplished by a piezoelectrically actuated micropipet. To reduce evaporation while pipetting the assays, the NTP was handled in a closed humid chamber and cooled to the point of condensation. To avoid washing steps, a homogeneous assay was developed that was based on energy-transfer (ET). As a model system, an antibody-based assay for the detection of the environmentally relevant compound, simazine, in drinking water was chosen. Antibodies were labeled with the long-wavelength-excitable sulfoindocyanine dye Cy5 (donor), and a tracer was synthesized by labeling BSA with a triazine derivative and the acceptor dye Cy5.5. At low analyte concentrations, the tracer was preferably bound to the antibody binding sites. As a result of the close proximity of Cy5.5 and Cy5, an efficient quenching of the Cy5 fluorescence occurred. Higher analyte concentrations led to a progressive binding of the analyte to the antibody binding sites. The increased Cy5 fluorescence was determined by using a scanning laser-induced fluorescence detector. The limit of detection (LOD), using an antibody concentration of 20 nM, was 0.32 microg/L, or 1.11 x 10(-16) mol of simazine. In comparison, the LOD of the 96-well microtiter-plate-based ET immunoassay (micro-ETIA) was 0.15 microg/L, or 1.87 x 10(-13) mol. The LOD of the optimized micro-ETIA at 1 nM IgG, was 0.01 microg/L. PMID:11721915

  10. Association of aminothiols with the clinical outcome in hemodialysis patients: comparison of chromatography and immunoassay for homocysteine determination

    E-print Network

    Paris-Sud XI, Université de

    by high performance liquid chromatography (HPLC) and fluorescence polarization immunoassay (FPIA :confidence interval CV: cardiovascular ESRD: end stage renal disease FPIA: fluorescence polarization of chromatography and immunoassay for homocysteine determination Stéphanie Badiou1 , Nathalie Terrier1 , Isabelle

  11. NCI at Frederick: Research Donor Program (RDP)

    Cancer.gov

    The Research Donor Program (RDP) serves as a central repository for the collection and distribution of whole blood samples from healthy volunteers to the Frederick National Lab Investigators for in vitro research use. Approved projects can obtain timely and inexpensive samples through OHS. Employees of the Frederick National Lab and Fort Detrick community may volunteer to be donors. Monetary compensation is provided for donor participation. The program is administered by Occupational Health Services.

  12. MDCT angiography of living laparoscopic renal donors

    Microsoft Academic Search

    S. Kawamoto; E. K. Fishman

    2006-01-01

    Laparoscopic donor nephrectomy has become the accepted method of harvesting the kidney at many institutions because of multiple\\u000a advantages over open donor nephrectomy. Spiral computed tomographic (CT) angiography provides accurate information of renal\\u000a vascular anatomy and has become an accepted method of preoperative evaluation of potential laparoscopic renal donors. More\\u000a recently, multidetector CT (MDCT) provides more detailed datasets compared with

  13. NCI at Frederick: Donor Eligibility and Enrollment

    Cancer.gov

    Establishment of the RDP donor pool is accomplished by voluntary employee enrollment. Individuals must be employees of the Frederick National Lab or Fort Detrick community, must be age 18 or older, and weigh at least 110 pounds to be eligible for inclusion in the RDP donor pool. In addition, donors must attend a scheduled RDP Counseling meeting and submit to select blood-borne pathogen and CBC testing upon inclusion and every six months thereafter.

  14. Seroepidemiology of Toxoplasma gondii Infection among Healthy Blood Donors in Taiwan

    PubMed Central

    Chiang, Ting-Yi; Hsieh, Hwei-Ho; Kuo, Ming-Chu; Chiu, Kai-Tse; Lin, Wei-Chen; Fan, Chia-Kwung; Fang, Chi-Tai; Ji, Dar-Der

    2012-01-01

    Toxoplasma gondii is an opportunistic, zoonotic pathogen with a worldwide distribution. There are large variations in the seroprevalence of T. gondii infection in different regions of the world. Although toxoplasmosis became a notifiable communicable disease in Taiwan in 2007, little is known about its epidemiology among the general population. This cross-sectional study aimed to survey the seroprevalence of T. gondii infection and its risk factors among healthy blood donors in Taiwan. Through collaborating with the Taiwan Blood Services Foundation, a total of 1,783 healthy blood donors from all six-branch blood service centers participated in this study. The blood samples were tested for the presence of T. gondii antibodies and DNA using enzyme immunoassays and real-time PCR, respectively. Structured questionnaires were used to gather information on risk factors for T. gondii infection. Of the 1,783 participants, 166 (9.3%) tested positive for anti-Toxoplasma IgG, while 5 (0.28%) tested positive for anti-Toxoplasma IgM. The five IgM positive donors had high avidity antibodies suggestive of past infection. No active parasitemia was detected by real-time PCR assays. Multivariate logistic regression showed that undercooked pork meat consumption (adjusted odds ratio [OR]?=?2.9; 95% confidence interval [CI]: 1.3–6.5), raw mussels consumption (adjusted OR?=?5.3; 95% CI: 1.5–19.1), having a cat in the household (adjusted OR?=?2.0; 95% CI: 1.2–3.2), a lower education level (adjusted OR?=?1.6; 95% CI: 1.1–2.3), and donation place in eastern Taiwan (adjusted OR?=?2.5; 95% CI: 1.6–3.9) were independent risk factors for Toxoplasma seropositivity. These findings provide information on the seroprevalence and epidemiology of T. gondii infection among healthy blood donors in Taiwan. PMID:23133557

  15. Shallow donors in GaN.

    SciTech Connect

    Lee, S. K. (Samsung Advanced Institute of Technology, Suwon, Korea); Koleske, Daniel David; Moore, W. J. (SFA, Inc., Largo, MD); Freitas, J. A., Jr. (Naval Research Laboratory, Washington, DC); Shanabrook, B. V. (Naval Research Laboratory, Washington, DC); Braga, G. C. B. (Naval Research Laboratory, Washington, DC); Han, J. Y. (Samsung Advanced Institute of Technology, Suwon, Korea); Park, S. S. (Samsung Advanced Institute of Technology, Suwon, Korea)

    2004-06-01

    High-resolution, variable temperature PL experiments were performed in the spectral region associated with recombination processes involving the ground and excited states of the neutral donor bound excitons. High-resolution infrared measurements in combination with high-sensitive SIMS unambiguously identified Si and O shallow donors and yield their ground state binding energies. These binding energies are in excellent agreement with values obtained by the analysis of the two-electron-satellite PL spectra considering the participation of ground and excited state donor bound excitons. This work clarifies conflicting aspects existing in donor identification and the binding energies of the impurities and excitons.

  16. REGGI and the American Rare Donor Program

    PubMed Central

    Flickinger, Cynthia

    2014-01-01

    Summary The American Rare Donor Program (ARDP) was formed in 1998 to provide rare blood units for patients in need. Members of the program identify rare donors and submit donor information for entrance into a database, REGGI. Information on patients in need of rare blood is also submitted and entered into REGGI. REGGI serves to match phenotypes of registered donors with patients having the respective antibodies. A search process for available units ensues, and blood is provided to the patient. This report provides information on REGGI and its use in the ARDP. PMID:25538535

  17. Living-donor liver transplantation: current perspective.

    PubMed

    Lobritto, Steven; Kato, Tomoaki; Emond, Jean

    2012-11-01

    The disparity between the number of available deceased liver donors and the number of patients awaiting transplantation continues to be an ongoing issue predisposing to death on the liver transplant waiting list. Deceased donor shortage strategies including the use of extended donor-criteria deceased donor grafts, split liver transplants, and organs harvested after cardiac death have fallen short of organ demand. Efforts to raise donor awareness are ongoing, but the course has been arduous to date. Living donor transplantation is a means to access an unlimited donor organ supply and offers potential advantages to deceased donation. Donor safety remains paramount demanding improvements and innovations in both the donor and recipient operations to ensure superior outcomes. The specialty operation is best preformed at centers with specific expertise and shuttling of select patients to these centers supported by third party payers is critical. Training future surgeons at centers with this specific experience can help disseminate this technology to improve local availability. Ongoing research in immunosuppression minimization, withdrawal and tolerance induction may make living donation a desired first-line operation rather than a necessary albeit less-desirable option. This chapter summarizes the progress of living liver donation and its potential applications. PMID:23397534

  18. Dynamic donor–acceptor [2]catenanes

    PubMed Central

    Miljani?, Ognjen Š; Stoddart, J. Fraser

    2007-01-01

    Donor–acceptor [2]catenanes based on cyclobis(paraquat-p-phenylene) as the ?-acceptor ring have been used prominently in the construction of functional molecular devices. We report here their thermodynamically controlled synthesis from isolated ?-donor and ?-acceptor rings under the catalytic influence of tetra butylammonium iodide. The initial nucleophilic attack of iodide ion, which opens up the ?-acceptor ring, is followed by complexation to the ?-donor ring and the subsequent catenation of the ?-donor ring by the ?-acceptor ring [2]catenane. The reaction is general in scope and proceeds in high yields, without giving rise to side-products. PMID:17670941

  19. Hybrid super electron donors – preparation and reactivity

    PubMed Central

    Garnier, Jean; Thomson, Douglas W; Zhou, Shengze; Jolly, Phillip I; Berlouis, Leonard E A

    2012-01-01

    Summary Neutral organic electron donors, featuring pyridinylidene–imidazolylidene, pyridinylidene–benzimidazolylidene and imidazolylidene–benzimidazolylidene linkages are reported. The pyridinylidene–benzimidazolylidene and imidazolylidene–benzimidazolylidene hybrid systems were designed to be the first super electron donors to convert iodoarenes to aryl radicals at room temperature, and indeed both show evidence for significant aryl radical formation at room temperature. The stronger pyridinylidene–imidazolylidene donor converts iodoarenes to aryl anions efficiently under appropriate conditions (3 equiv of donor). The presence of excess sodium hydride base has a very important and selective effect on some of these electron-transfer reactions, and a rationale for this is proposed. PMID:23019427

  20. Kinetic determination of atrazine in foods based on stopped-flow fluorescence polarization immunoassay

    Microsoft Academic Search

    B Sendra; S Panadero; S Eremin; A Gómez-Hens

    1998-01-01

    A very simple and fast method for the direct determination of atrazine in food samples based on the use of stopped-flow fluorescence polarization immunoassay is described. Unlike other immunoassay methods where the analytical signal is obtained when the immunochemical reaction has reached or is close to the equilibrium, this method uses the initial rate of this reaction as the analytical

  1. Simultaneous Detection of Antibodies to Six Nonhuman-Primate Viruses by Multiplex Microbead Immunoassay

    Microsoft Academic Search

    Imran H. Khan; Sara Mendoza; JoAnn Yee; Matthew Deane; Kodumudi Venkateswaran; Shan S. Zhou; Peter A. Barry; Nicholas W. Lerche; Paul A. Luciw

    2006-01-01

    To maintain healthy nonhuman primates for use in biomedical research, animals are routinely screened for several infectious agents at most facilities. Commonly, monkey serum samples are tested by conventional immunoassays, such as enzyme-linked immunosorbent assays (ELISAs) or Western blotting, for antibodies to specific infectious agents. For testing for antibodies against multiple agents in each sample, conventional immunoassays are laborious and

  2. Europium chelate labels in time-resolved fluorescence immunoassays and DNA hybridization assays

    Microsoft Academic Search

    Eleftherios P. Diamandis; Theodore K. Christopoulos

    1990-01-01

    Like many analytical methodologies, immunoassays and nucleic acid hybridization assays rely on the reaction between an analyte of interest and a specific reagent. The analyte concentration is then deduced by measuring either the amount of analyte-reagent complex formed (product) or the amount of residual reagent. The authors describe the application of fluorescent rare-earth chelates to immunoassay and DNA probing.

  3. Isolation of Alpaca Anti-Hapten Heavy Chain Single Domain Antibodies for Development of Sensitive Immunoassay

    E-print Network

    Hammock, Bruce D.

    Isolation of Alpaca Anti-Hapten Heavy Chain Single Domain Antibodies for Development of Sensitive of immunoassay. We expressed VHHs from an immunized alpaca and developed a VHH-based immunoassay using 3-phenox sequences from immunized alpaca and phage display technology for antibody selection. Since the first

  4. : A Portable, Multiplexed Immunoassay Platform Differentiating Advantages of SpinDxTM

    E-print Network

    Singh, Anup

    SpinDxTM : A Portable, Multiplexed Immunoassay Platform Differentiating Advantages of SpinDxTM userdefined assays · Compatible with many matrices: Whole blood, serum, saliva, urine, water, milk, and food · Multiplexed immunoassays: Up to 64 parallel assays from a single sample · Cost Effective: assay

  5. Europium chelate labels in time-resolved fluorescence immunoassays and DNA hybridization assays

    SciTech Connect

    Diamandis, E.P.; Christopoulos, T.K. (Toronto Western Hospital, Ontario (Canada) Univ. of Toronto, Ontario (Canada))

    1990-11-15

    Like many analytical methodologies, immunoassays and nucleic acid hybridization assays rely on the reaction between an analyte of interest and a specific reagent. The analyte concentration is then deduced by measuring either the amount of analyte-reagent complex formed (product) or the amount of residual reagent. The authors describe the application of fluorescent rare-earth chelates to immunoassay and DNA probing.

  6. ULTRASENSITIVE IMMUNOASSAYS BASED ON SURFACE-ENHANCED RAMAN SCATTERING BY IMMUNOGOLD LABELS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes recent advances in the use of surface-enhanced Raman Scattering (SERS) as a readout tool for chip-scale, sandwich-based immunoassays. It reviews progress made in developing SERS-based immunoassays for a wide range of biolytes, including proteins, viruses and bacteria. The st...

  7. AN ENVIRONMENTAL TECHNOLOGY VERIFICATION (ETV) TESTING OF THREE IMMUNOASSAY TEST KITS FOR ANTHRAX, BOTULINUM TOXIN AND RICIN

    EPA Science Inventory

    Immunoassay test kits are based on immunoassay methods, where specific antibodies are used to detect and measure the contaminants of interest. Immunoassay test kits rely on the reaction of a contaminant or antigen with a selective antibody to give a product that can be measures....

  8. Comparison of a Time-Resolved Fluorescence Immunoassay and an Enzyme-Linked Immunosorbent Assay for the Analysis of Atrazine

    E-print Network

    Hammock, Bruce D.

    Comparison of a Time-Resolved Fluorescence Immunoassay and an Enzyme-Linked Immunosorbent Assay of California, Davis, California 95616 Immunoassays for atrazine based on a time-resolved fluorescent label immunoassay (TRFIA) was based on a polyclonal antibody and a europium label, whereas the enzyme

  9. PAPER www.rsc.org/loc | Lab on a Chip Microfluidic device for immunoassays based on surface plasmon resonance

    E-print Network

    Zare, Richard N.

    PAPER www.rsc.org/loc | Lab on a Chip Microfluidic device for immunoassays based on surface plasmon to about 60 min. Introduction Immunoassays, such as the enzyme-linked immunosorbent assay (ELISA), have-step immunoassays. This feature limits their applications, especially when the detection method is sensitive

  10. The use of glass substrates with bi-functional silanes for designing micropatterned cell-secreted cytokine immunoassays

    E-print Network

    Ferrara, Katherine W.

    -secreted cytokine immunoassays Jeong Hyun Seo a , Li-Jung Chen b , Stanislav V. Verkhoturov b , Emile A. Schweikert Keywords: Cell function Cytokine release and immune cells Cytokine detection Immunoassay Cell microwells. Our aim was to increase sensitivity of micropatterned cytokine immunoassays through covalent

  11. Effect of volume-and time-based constraints on capture of analytes in microfluidic heterogeneous immunoassays

    E-print Network

    Sia, Samuel K.

    immunoassays Hesam Parsa,x Curtis D. Chin,x Puttisarn Mongkolwisetwara, Benjamin W. Lee, Jennifer J. Wang immunoassays (where analytes in solution are captured on a solid surface functionalized with a capture molecule to advantages in size, volume requirement, and time to analysis.1­6 In particular, heterogeneous immunoassays,7

  12. A Fast Universal Immobilization of Immunoglobulin G at 4uC for the Development of Array-based Immunoassays

    E-print Network

    Lee, H.C. Paul

    -based Immunoassays Shu-Lin Guo1,2. , Po-Chung Chen1. , Ming-Shuo Chen1. , Yu-Che Cheng3,4 , Jun-Mu Lin1 , Hoong activity and enhance performance of array-based immunoassays, protein G was used to allow a shorter of array- based immunoassays: substance P, calcitonin gene-related peptide, nerve growth factor, brain

  13. Micromotor-based lab-on-chip immunoassays

    NASA Astrophysics Data System (ADS)

    García, Miguel; Orozco, Jahir; Guix, Maria; Gao, Wei; Sattayasamitsathit, Sirilak; Escarpa, Alberto; Merkoçi, Arben; Wang, Joseph

    2013-01-01

    Here we describe the first example of using self-propelled antibody-functionalized synthetic catalytic microengines for capturing and transporting target proteins between the different reservoirs of a lab-on-a-chip (LOC) device. A new catalytic polymer/Ni/Pt microtube engine, containing carboxy moieties on its mixed poly(3,4-ethylenedioxythiophene) (PEDOT)/COOH-PEDOT polymeric outermost layer, is further functionalized with the antibody receptor to selectively recognize and capture the target protein. The new motor-based microchip immunoassay operations are carried out without any bulk fluid flow, replacing the common washing steps in antibody-based protein bioassays with the active transport of the captured protein throughout the different reservoirs, where each step of the immunoassay takes place. A first microchip format involving an `on-the-fly' double-antibody sandwich assay (DASA) is used for demonstrating the selective capture of the target protein, in the presence of excess of non-target proteins. A secondary antibody tagged with a polymeric-sphere tracer allows the direct visualization of the binding events. In a second approach the immuno-nanomotor captures and transports the microsphere-tagged antigen through a microchannel network. An anti-protein-A modified microengine is finally used to demonstrate the selective capture, transport and convenient label-free optical detection of a Staphylococcus aureus target bacteria (containing proteinA in its cell wall) in the presence of a large excess of non-target (Saccharomyces cerevisiae) cells. The resulting nanomotor-based microchip immunoassay offers considerable potential for diverse applications in clinical diagnostics, environmental and security monitoring fields.Here we describe the first example of using self-propelled antibody-functionalized synthetic catalytic microengines for capturing and transporting target proteins between the different reservoirs of a lab-on-a-chip (LOC) device. A new catalytic polymer/Ni/Pt microtube engine, containing carboxy moieties on its mixed poly(3,4-ethylenedioxythiophene) (PEDOT)/COOH-PEDOT polymeric outermost layer, is further functionalized with the antibody receptor to selectively recognize and capture the target protein. The new motor-based microchip immunoassay operations are carried out without any bulk fluid flow, replacing the common washing steps in antibody-based protein bioassays with the active transport of the captured protein throughout the different reservoirs, where each step of the immunoassay takes place. A first microchip format involving an `on-the-fly' double-antibody sandwich assay (DASA) is used for demonstrating the selective capture of the target protein, in the presence of excess of non-target proteins. A secondary antibody tagged with a polymeric-sphere tracer allows the direct visualization of the binding events. In a second approach the immuno-nanomotor captures and transports the microsphere-tagged antigen through a microchannel network. An anti-protein-A modified microengine is finally used to demonstrate the selective capture, transport and convenient label-free optical detection of a Staphylococcus aureus target bacteria (containing proteinA in its cell wall) in the presence of a large excess of non-target (Saccharomyces cerevisiae) cells. The resulting nanomotor-based microchip immunoassay offers considerable potential for diverse applications in clinical diagnostics, environmental and security monitoring fields. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr32400h

  14. Multifunctional nanoparticles as simulants for a gravimetric immunoassay

    PubMed Central

    Miller, Scott A.; Hiatt, Leslie A.; Keil, Robert G.; Wright, David W.; Cliffel, David E.

    2011-01-01

    Immunoassays are important tools for the rapid detection and identification of pathogens, both clinically and in the research laboratory. An immunoassay with the potential for the detection of influenza was developed and tested using hemagglutinin (HA), a commonly studied glycoprotein found on the surface of influenza virions. Gold nanoparticles were synthesized, which present multiple peptide epitopes, including the HA epitope, in order to increase the gravimetric response achieved with the use of a QCM immunosensor for influenza. Specifically, epitopes associated with HA and FLAG peptides were affixed to gold nanoparticles by a sixmer PEG spacer between the epitope and the terminal cysteine. The PEG spacer was shown to enhance the probability for interaction with antibodies by increasing the distance the epitope extends from the gold surface. These nanoparticles were characterized using thermogravimetric analysis, transmission electron microscopy, matrix-assisted laser desorption/ionization-time of flight, and 1H nuclear magnetic resonance analysis. Anti-FLAG and anti-HA antibodies were adhered to the surface of a QCM, and the response of each antibody upon exposure to HA, FLAG, and dual functionalized nanoparticles was compared with binding of Au–tiopronin nanoparticles and H5 HA proteins from influenza virus (H5N1). Results demonstrate that the immunoassay was capable of differentiating between nanoparticles presenting orthogonal epitopes in real-time with minimal nonspecific binding. The detection of H5 HA protein demonstrates the logical extension of using these nanoparticle mimics as a safe positive control in the detection of influenza, making this a vital step in improving influenza detection methodology. PMID:21110011

  15. Performance characteristics of three automated immunoassays for thyroid hormones

    PubMed Central

    Kazerouni, Faranak; Amirrasouli, Houshang

    2012-01-01

    Background: Since the introduction of the first radioimmunoassay, several improvements have been made in the design of immunoassays such as method of antibody production, labeling, automation and detection technology. We performed an analytical evaluation of the new electrochemiluminescent immunoassay (ECLIA) for serum TSH, FT4 and T3 in the Elecsys 2010 immunoassay system and compared the results of this method with those of radioimmunoassay ( RIA) [immunoradiometric (IRMA) for TSH] and Elisa. Methods: Fasting serum from 112 hypo, hyper and euthyroid patients were used to evaluate the minimum detectable concentration, intra- and inter-assay precisions for TSH, FT4, T3, linearity for TSH assay and method comparison study. Results: Within the analytical range tested, intra-assay coefficient of variation was < 2.3% for TSH, 2.3% for FT4 and 7.8% for T3. The inter-assay coefficient of variation was < 2.9% for TSH, 2.5% for FT4 and 12.3% for T3. The measurement of diluted sera indicated a desirable percentage of recovery for TSH. No correlation was found between Elecsys 2010 and Elisa /IRMA for TSH. The comparison of results of the Elecsys ECLIA assay with those of Elisa and RIA for T4 were: T4 (ECLIA) = -0.612+0.999, T4 (Elisa, r= 0.88) and T4 (ECLIA)=0.642+0.942 T4 (RIA, r=0.957), while ECLIA assay with Elisa and RIA for T3 were: T3 (ECLIA)= 0.242+0.908 T3 (Elisa, r=0.8) and T3 (ECLIA) = -0.029+1.01 T3 (RIA, r=0.957). Conclusion: The results show that Elecsys 2010 is an automated reliable, efficient and technically excellent instrument to use in the measurement of serum TSH, T4 and T3. PMID:24358433

  16. Fast and sensitive detection of enteropathogenic Yersinia by immunoassays.

    PubMed

    Laporte, Jérôme; Savin, Cyril; Lamourette, Patricia; Devilliers, Karine; Volland, Hervé; Carniel, Elisabeth; Créminon, Christophe; Simon, Stéphanie

    2015-01-01

    Yersinia enterocolitica and Yersinia pseudotuberculosis, the two Yersinia species that are enteropathogenic for humans, are distributed worldwide and frequently cause diarrhea in inhabitants of temperate and cold countries. Y. enterocolitica is a major cause of foodborne disease resulting from consumption of contaminated pork meat and is further associated with substantial economic cost. However, investigation of enteropathogenic Yersinia species is infrequently performed routinely in clinical laboratories because of their specific growth characteristics, which make difficult their isolation from stool samples. Moreover, current isolation procedures are time-consuming and expensive, thus leading to underestimates of the incidence of enteric yersiniosis, inappropriate prescriptions of antibiotic treatments, and unnecessary appendectomies. The main objective of the study was to develop fast, sensitive, specific, and easy-to-use immunoassays, useful for both human and veterinary diagnosis. Monoclonal antibodies (MAbs) directed against Y. enterocolitica bioserotypes 2/O:9 and 4/O:3 and Y. pseudotuberculosis serotypes I and III were produced. Pairs of MAbs were selected by testing their specificity and affinity for enteropathogenic Yersinia and other commonly found enterobacteria. Pairs of MAbs were selected to develop highly sensitive enzyme immunoassays (EIAs) and lateral flow immunoassays (LFIs or dipsticks) convenient for the purpose of rapid diagnosis. The limit of detection of the EIAs ranged from 3.2 × 10(3) CFU/ml to 8.8 × 10(4) CFU/ml for pathogenic serotypes I and III of Y. pseudotuberculosis and pathogenic bioserotypes 2/O:9 and 4/O:3 of Y. enterocolitica and for the LFIs ranged from 10(5) CFU/ml to 10(6) CFU/ml. A similar limit of detection was observed for artificially contaminated human feces. PMID:25355759

  17. Laparoscopic Donor Nephrectomy at a Low Volume Living Donor Transplant Center: Successful Outcomes can be Expected

    Microsoft Academic Search

    DAVID A. DUCHENE; D. BROOKE JOHNSON; SHUJUN LI; JAY S. RODEN; ARTHUR I. SAGALOWSKY; JEFFREY A. CADEDDU

    2003-01-01

    PurposeConcern has been raised about possible increased morbidity associated with laparoscopic donor nephrectomy (LDN) during the learning curve of the procedure and at centers with a low volume of living donors. We evaluated the safety and success of LDN at a low volume living donor transplant center with a skilled laparoscopic urologist and experienced renal transplant team.

  18. “Egg Donor Wanted”: Social Work with Women Looking for an Egg Donor

    Microsoft Academic Search

    Vivien Hart; Debbie Plath

    2011-01-01

    Women seeking fertility treatment using donor eggs can face challenges associated with recruiting suitable egg donors and negotiating the role that the donor may play in the life of the child. Social work in infertility clinics is an emerging area of practice and social work counsellors have an important role to play with parties involved in the egg donation process.

  19. The Living Organ Donor Network: a model registry for living kidney donors.

    PubMed

    McCune, Thomas R; Armata, Thomas; Mendez-Picon, Gerardo; Yium, Jackson; Zabari, Gazi B; Crandall, Betty; Spicer, Helen G; Blanton, Jack; Thacker, Leroy R

    2004-01-01

    The South-Eastern Organ Procurement Foundation presents the first report on a programme to track donors through questionnaires completed at the time of donation, 3 months, 6 months, and yearly thereafter. Donors at participating centres were eligible for an insurance policy with a total benefit of 250,000 US dollars, covering accidental death related to donation, surgery, medical expenses of complications, and disability income. The four participating centres have registered 104 donors. Response rate to the questionnaires was 90.91%. The majority of the donors come from the immediate family (81.62%), either by blood or marriage. The majority of donors are employed full time, with income ranges similar to the national census. Donors rely on employer-provided vacation time and sick leave to recuperate, but the average donor required 12 days of unpaid leave before returning to work. Donors also experienced costs of transportation, lodging, and childcare. Anti-depressants were prescribed to 10.58% of donors, and 4.8% of donors reported they are treated for hypertension. Complications were reported by 37.5% of the donors, but only 7.6% of the complications were serious enough to require hospitalization or surgery. Donors reported higher complication rates than reported by the centres and experience financial burdens afterwards. PMID:15217405

  20. Immunoassay Methods and their Applications in Pharmaceutical Analysis: Basic Methodology and Recent Advances

    PubMed Central

    Darwish, Ibrahim A.

    2006-01-01

    Immunoassays are bioanalytical methods in which the quantitation of the analyte depends on the reaction of an antigen (analyte) and an antibody. Immunoassays have been widely used in many important areas of pharmaceutical analysis such as diagnosis of diseases, therapeutic drug monitoring, clinical pharmacokinetic and bioequivalence studies in drug discovery and pharmaceutical industries. The importance and widespread of immunoassay methods in pharmaceutical analysis are attributed to their inherent specificity, high-throughput, and high sensitivity for the analysis of wide range of analytes in biological samples. Recently, marked improvements were achieved in the field of immunoassay development for the purposes of pharmaceutical analysis. These improvements involved the preparation of the unique immunoanalytical reagents, analysis of new categories of compounds, methodology, and instrumentation. The basic methodologies and recent advances in immunoassay methods applied in different fields of pharmaceutical analysis have been reviewed. PMID:23674985

  1. Species Specific Bacterial Spore Detection Using Lateral-Flow Immunoassay with DPA-Triggered Tb Luminescence

    NASA Technical Reports Server (NTRS)

    Ponce, Adrian

    2003-01-01

    A method of detecting bacterial spores incorporates (1) A method of lateral-flow immunoassay in combination with (2) A method based on the luminescence of Tb3+ ions to which molecules of dipicolinic acid (DPA) released from the spores have become bound. The present combination of lateral-flow immunoassay and DPA-triggered Tb luminescence was developed as a superior alternative to a prior lateral-flow immunoassay method in which detection involves the visual observation and/or measurement of red light scattered from colloidal gold nanoparticles. The advantage of the present combination method is that it affords both (1) High selectivity for spores of the species of bacteria that one seeks to detect (a characteristic of lateral-flow immunoassay in general) and (2) Detection sensitivity much greater (by virtue of the use of DPA-triggered Tb luminescence instead of gold nanoparticles) than that of the prior lateral-flow immunoassay method

  2. [Detection of fish protein in food products by lateral flow immunoassay].

    PubMed

    Shibahara, Yusuke; Ii, Toshihiro; Wang, Jun; Yamada, Shoichi; Shiomi, Kazuo

    2014-01-01

    The major fish allergen is parvalbumin, a sarcoplasmic protein. In this study, a novel lateral flow immunoassay for the detection of fish protein in food products was developed using a polyclonal antibody raised against Pacific mackerel Scomber japonicus parvalbumin. The proposed lateral flow immunoassay showed high reactivity to various fish parvalbumins, but the reactivity to bullfrog parvalbumin was very low. The detection limit of the immunoassay for fish parvalbumin was estimated to be 2.0 ?g protein/g, which matches the sensitivity required in the current Japanese food labeling system. Furthermore, the lateral flow immunoassay could detect fish parvalbumin without being affected by food matrices and was applicable even to heat-denatured parvalbumin. These results showed that the lateral flow immunoassay developed in this study is specific to fish parvalbumin, and should be useful as a rapid detection method for fish protein in processed food products. PMID:24990554

  3. Dot-blot enzyme immunoassay for the detection of bovine viral Dot-blot enzyme immunoassay for the detection of bovine viral diarrhea virus antibodies diarrhea virus antibodies

    Microsoft Academic Search

    Farhid Hemmatzadeh; Farhad Amini

    ABSTRACT Dot-blot enzyme immunoassay (DB-EIA) was utilized for the detection of bovine viral diarrhea (BVD) Dot-blot enzyme immunoassay (DB-EIA) was utilized for the detection of bovine viral diarrhea (BVD) antibodies in infected cattle. In this assay whole particles of the NADL strain of BVD virus were used as antibodies in infected cattle. In this assay whole particles of the NADL

  4. Chemiluminescence enzyme immunoassay using ProteinA-bacterial magnetite complex

    NASA Astrophysics Data System (ADS)

    Matsunaga, Tadashi; Sato, Rika; Kamiya, Shinji; Tanaka, Tsuyosi; Takeyama, Haruko

    1999-04-01

    Bacterial magnetic particles (BMPs) which have ProteinA expressed on their surface were constructed using magA which is a key gene in BMP biosynthesis in the magnetic bacterium Magnetospirillum sp. AMB-1. Homogenous chemiluminescence enzyme immunoassay using antibody bound ProteinA-BMP complexes was developed for detection of human IgG. A good correlation between the luminescence yield and the concentration of human IgG was obtained in the range of 1-10 3 ng/ml.

  5. Fluorescence polarization immunoassay for salinomycin based on monoclonal antibodies

    Microsoft Academic Search

    ZhanHui Wang; LinLi Cheng; WeiMin Shi; SuXia Zhang; JianZhong Shen

    2010-01-01

    A fluorescence polarization immunoassay (FPIA) for the determination of salinomycin (SAL) was developed by using anti-SAL\\u000a monoclonal antibodies (mAb). Fluorescein labeled SAL (tracer) was synthesized by the N-hydroxysuccinimide active ester method\\u000a and purified using thin layer chromatography (TLC). The developed FPIA for SAL had a dynamic range from 0.60 to 2193 ng\\/mL\\u000a with an IC50 value of 33.2 ng\\/mL and

  6. Pholcodine interference in the immunoassay for opiates in urine.

    PubMed

    Svenneby, G; Wedege, E; Karlsen, R L

    1983-01-01

    The excretion in urine after single oral therapeutic doses of morphine derivatives was analysed with radioimmunoassay (RIA) and homogeneous enzyme immunoassay (EMIT) for opiates. In contrast to the rapid excretion of ethylmorphine and codeine, pholcodine showed positive results for opiates 2-6 weeks after intake when the urines were analysed with the RIA-method. When analysed with the EMIT-method, positive results were obtained for pholcodine for approximately 10 days. As pholcodine is a common component in cough mixtures, its prolonged excretion could represent a hazard in interpreting the results from drug analyses of urines. PMID:6347841

  7. Immunoassay - is there a future role for nuclear medicine

    SciTech Connect

    Witherspoon, L.R.

    1983-10-01

    In this article with 174 references the evolution, current status, and potential future of immunoassay technology in the clinical laboratory are considered. Current and future applications of these methods are also considered. This article is not intended to be a review; rather it is an attempt to examine the role nuclear medicine may play in the future application of these techniques. In addition, while recognizing the dangers inherent in treating so much material superficially, the author attempts to document the ideas discussed to that the reader may turn to more detailed literature if stimulated to do so.

  8. Tumor specific lung cancer diagnostics with multiplexed FRET immunoassays

    NASA Astrophysics Data System (ADS)

    Geißler, D.; Hill, D.; Löhmannsröben, H.-G.; Thomas, E.; Lavigne, A.; Darbouret, B.; Bois, E.; Charbonnière, L. J.; Ziessel, R. F.; Hildebrandt, N.

    2010-02-01

    An optical multiplexed homogeneous (liquid phase) immunoassay based on FRET from a terbium complex to eight different fluorescent dyes is presented. We achieved highly sensitive parallel detection of four different lung cancer specific tumor markers (CEA, NSE, SCC and CYFRA21-1) within a single assay and show a proof-of-principle for 5- fold multiplexing. The method is well suited for fast and low-cost miniaturized point-of-care testing as well as for highthroughput screening in a broad range of in-vitro diagnostic applications.

  9. Demonstration of four immunoassay formats using the array biosensor

    NASA Technical Reports Server (NTRS)

    Sapsford, Kim E.; Charles, Paul T.; Patterson, Charles H Jr; Ligler, Frances S.

    2002-01-01

    The ability of a fluorescence-based array biosensor to measure and quantify the binding of an antigen to an immobilized antibody has been demonstrated using the four different immunoassay formats: direct, competitive, displacement, and sandwich. A patterned array of antibodies specific for 2,4,6-trinitrotoluene (TNT) immobilized onto the surface of a planar waveguide and used to measure signals from different antigen concentrations simultaneously. For direct, competitive, and displacement assays, which are one-step assays, measurements were obtained in real time. Dose-response curves were calculated for all four assay formats, demonstrating the array biosensor's ability to quantify the amount of antigen present in solution.

  10. Monoclonal antibody based immunoassays for cooking-induced meat mutagens

    SciTech Connect

    Vanderlaan, M.; Hwang, M.; Knize, M.G.; Watkins, E.; Felton, J.S.

    1989-06-29

    We report here new monoclonal antibodies (Mabs) numbered AIA-8 through AIA-12 produced using the same methods used to produce AIA-1, and a new Mab, IQ-7, produced with the same methods used for IQ-1. Our motivation in seeking these new clones was to increase the repertoire of available Mabs to insure adequate coverage of all known AIAs. Also, the mice used to produce these new hybridoma clones had been immunized about six months longer than those used to generate the first clones. Longer immunization is often associated with higher affinity Mabs and therefore more sensitive competition immunoassays. 15 refs., 2 figs., 2 tabs.

  11. The Experience of Living Kidney Donors

    ERIC Educational Resources Information Center

    Brown, Judith Belle; Karley, Mary Lou; Boudville, Neil; Bullas, Ruth; Garg, Amit X.; Muirhead, Norman

    2008-01-01

    This article describes the experiences, feelings, and ideas of living kidney donors. Using a phenomenological, qualitative research approach, the authors interviewed 12 purposefully selected living kidney donors (eight men and four women), who were between four and 29 years since donation. Interviews were audiotaped, and transcribed verbatim, and…

  12. Transmission of cancer with cadaveric donor kidneys

    Microsoft Academic Search

    H. Oesterwitz; K. Lucius; W. Blank

    1990-01-01

    From 3 donors suffering from extracerebral cancer 5 kidneys have been transplanted. All grafts functioned well without tumour\\u000a signs up to 21 months after transplantation. However, because of tumour recurrence in nearly 50% of the cases recorded in\\u000a the Cincinnati Transplant Tumor Registry, generally organs from donors suffering from cancer should not be used.

  13. Challenges in living donor liver transplantation.

    PubMed

    Trotter, James F

    2014-08-01

    Living donor liver transplantation is a procedure that has waned in its application over the past decade but remains a beneficial procedure for properly selected candidates. This review discusses some of the newer, relevant studies in the field, focusing on outcomes with hepatocellular carcinoma, ABO-incompatible transplant, and issues in donor complications and safety. PMID:25017081

  14. 21 CFR 610.41 - Donor deferral.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...40(a), (b), and (e) subsequently may donate Source Plasma for use in the preparation of Hepatitis B Immune Globulin...due to HTLV, types I and II, may serve as a donor of Source Plasma; (5) A deferred donor who tests reactive for a...

  15. 21 CFR 610.41 - Donor deferral.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...40(a), (b), and (e) subsequently may donate Source Plasma for use in the preparation of Hepatitis B Immune Globulin...due to HTLV, types I and II, may serve as a donor of Source Plasma; (5) A deferred donor who tests reactive for a...

  16. MDCT angiography of living laparoscopic renal donors.

    PubMed

    Kawamoto, S; Fishman, E K

    2006-01-01

    Laparoscopic donor nephrectomy has become the accepted method of harvesting the kidney at many institutions because of multiple advantages over open donor nephrectomy. Spiral computed tomographic (CT) angiography provides accurate information of renal vascular anatomy and has become an accepted method of preoperative evaluation of potential laparoscopic renal donors. More recently, multidetector CT (MDCT) provides more detailed datasets compared with single-detector spiral CT and has been used for preoperative evaluation of laparoscopic donor nephrectomy to provide accurate anatomic information. MDCT (especially 16- and 64-slice MDCT) angiography has advantages over single-detector helical CT due to rapid scan time that allows coverage of a large volume of interest with higher spatial and temporal resolutions. In this article, we review the current status of MDCT angiography in the evaluation of laparoscopic renal donors and potential advantages of using this technology. PMID:16447094

  17. Preoperative Imaging Evaluation of Potential Living Liver Donors: Reasons for Exclusion From Donation in Adult Living Donor Liver Transplantation

    Microsoft Academic Search

    L. L.-C. Tsang; C.-L. Chen; T.-L. Huang; T.-Y. Chen; C.-C. Wang; H.-Y. Ou; L.-H. Lin; Y.-F. Cheng

    2008-01-01

    Accurate pretransplant evaluation of a potential donor in living donor liver transplantation (LDLT) is essential in preventing postoperative liver failure and optimizing safety. The aim of this study was to investigate the reasons for exclusion from donation of potential donors in adult LDLT. From September 2003 to June 2006, 266 potential donors were evaluated for 215 recipients: 220 potential donors

  18. Fast and sensitive detection of Bacillus anthracis spores by immunoassay.

    PubMed

    Morel, Nathalie; Volland, Hervé; Dano, Julie; Lamourette, Patricia; Sylvestre, Patricia; Mock, Michèle; Créminon, Christophe

    2012-09-01

    Bacillus anthracis is one of the most dangerous potential biological weapons, and it is essential to develop a rapid and simple method to detect B. anthracis spores in environmental samples. The immunoassay is a rapid and easy-to-use method for the detection of B. anthracis by means of antibodies directed against surface spore antigens. With this objective in view, we have produced a panel of monoclonal antibodies against B. anthracis and developed colorimetric and electrochemiluminescence (ECL) immunoassays. Using Meso Scale Discovery ECL technology, which is based on electrochemiluminescence (ECL) detection utilizing a sulfo-Tag label that emits light upon electrochemical stimulation (using a dedicated ECL plate reader, an electrical current is placed across the microplate with electrodes integrated into the bottom of the plate, resulting in a series of electrically induced reactions leading to a luminescent signal), a detection limit ranging between 0.3 × 10(3) and 10(3) CFU/ml (i.e., 30 to 100 spores per test), depending on the B. anthracis strain assayed, was achieved. In complex matrices (5 mg/ml of soil or simulated powder), the detection level (without any sample purification or concentration) was never altered more than 3-fold compared with the results obtained in phosphate-buffered saline. PMID:22773632

  19. A Sensitive Amphotericin B Immunoassay for Pharmacokinetic and Distribution Studies

    PubMed Central

    Machard, Sophie; Theodoro, Frederic; Benech, Henri; Grognet, Jean-Marc; Ezan, Eric

    2000-01-01

    Since currently used assays of amphotericin B (AMB) lack sensitivity or are not easily adaptable in all laboratories, we have developed an enzyme immunoassay for AMB in biological fluids and tissues. Antibodies to AMB were raised in rabbits after administration of an AMB-bovine serum albumin conjugate. The enzymatic tracer was obtained by coupling AMB via its amino group to acetylcholinesterase (EC 3.1.1.7). These reagents were used for the development of a competitive immunoassay performed on microtitration plates. The limit of quantification was 100 pg/ml in plasma and 1 ng/g in tissues. The plasma assay was performed directly without extraction on a minimal volume of 0.1 ml. The intra- and interassay coefficients of variation were in the range of 5 to 17%, and the recoveries were 92 to 111% for AMB added to human plasma. The assay was applied to a pharmacokinetic study with mice given AMB intraperitoneally at the dose of 1 mg/kg. The drug distribution in selected compartments (plasma, liver, spleen, lung, and brain) was monitored until 72 h after administration. In conclusion, our assay is at least 100-fold more sensitive than previously described bioassays or chromatographic determinations of AMB and may be useful in studying the tissue pharmacokinetics of new AMB formulations and in drug monitoring in clinical situations. PMID:10681316

  20. Microsphere-Based Immunoassay for the Detection of Azaspiracids

    PubMed Central

    Rodríguez, Laura P.; Vilariño, Natalia; Louzao, M. Carmen; Dickerson, Tobin J.; Nicolaou, K. C.; Frederick, Michael O.; Botana, Luis M.

    2014-01-01

    Azaspiracids (AZAs) are a group of lipophilic toxins discovered in mussels from Ireland in 1995 following a human poisoning incident. Nowadays the regulatory limit for AZAs in many countries is set at 160 Fg of azaspiracid equivalents per kg of shellfish meat. In this work a microsphere-based immunoassay has been developed for the detection of AZAs using a Luminex system. This method is based on the competition between AZA-2 immobilized onto the surface of microspheres and free AZAs for the interaction with a monoclonal anti-azaspiracid antibody (mAb 8F4). In this inhibition immunoassay the amount of mAb 8F4 bound to AZA-2-microspheres was quantified using a phycoerythrin-labeled anti-mouse antibody, and the fluorescence was measured with a Luminex analyzer. Simple acetate/methanol or methanol extractions yielded final extracts with no matrix interferences and adequate recovery rates of 86.5% and 75.8%, respectively. In summary, this work presents, a sensitive and easily performed screening method capable of detecting AZAs at concentrations below the range of the European regulatory limit using a microsphere/flow cytometry system. PMID:24215909

  1. The development of immunoassays for detection of chemical warfare agents

    SciTech Connect

    Lenz, D.E. [Army Medical Research Inst. of Chemical Defense, Aberdeen Proving Ground, MD (United States)

    1995-06-01

    With the advent of enzyme linked immunoabsorbant assays (ELISA) and monoclonal antibodies in the last two decades, there has been considerable effort devoted to the development of antibodies to detect and quantify low molecular weight toxic substances in environmental or biological fluids. Polyclonal antibodies against paraoxon (the toxic metabolite of parathion) were reported as capable of detecting paraoxon in body fluids at a level of 10{sup -9} M ({approximately}260 pg/mL) when used in a competitive inhibition enzyme immunoassay (CIEIA). Monoclonal antibodies developed against a structural analogue of the chemical warfare agent soman were capable of detecting soman in buffer solutions at a level of 10{sup -6} M ({approximately}180 ng/mL). In addition, these antibodies were highly specific for soman even in the presence of its major hydrolysis product. Subsequent studies with antisoman monoclonal antibodies reported an extension of the level of sensitivity to -80 ng/mL. Furthermore these antibodies did not cross react with other chemical warfare nerve agents such as sarin or tabun. In all cases, the time for a confirmatory test was two hours or less. Immunoassays for T-2 micotoxins have also been reported with a minimal detection range of 2 pg/assay to 50 ng/assay for the polyclonal and monoclonal T-2 antibodies respectively. These antibodies offer a sensitive, rapid and low cost approach to the diagnosis or detection of the presence of toxic chemical substances.

  2. Fast and Sensitive Detection of Bacillus anthracis Spores by Immunoassay

    PubMed Central

    Volland, Hervé; Dano, Julie; Lamourette, Patricia; Sylvestre, Patricia; Mock, Michèle; Créminon, Christophe

    2012-01-01

    Bacillus anthracis is one of the most dangerous potential biological weapons, and it is essential to develop a rapid and simple method to detect B. anthracis spores in environmental samples. The immunoassay is a rapid and easy-to-use method for the detection of B. anthracis by means of antibodies directed against surface spore antigens. With this objective in view, we have produced a panel of monoclonal antibodies against B. anthracis and developed colorimetric and electrochemiluminescence (ECL) immunoassays. Using Meso Scale Discovery ECL technology, which is based on electrochemiluminescence (ECL) detection utilizing a sulfo-Tag label that emits light upon electrochemical stimulation (using a dedicated ECL plate reader, an electrical current is placed across the microplate with electrodes integrated into the bottom of the plate, resulting in a series of electrically induced reactions leading to a luminescent signal), a detection limit ranging between 0.3 × 103 and 103 CFU/ml (i.e., 30 to 100 spores per test), depending on the B. anthracis strain assayed, was achieved. In complex matrices (5 mg/ml of soil or simulated powder), the detection level (without any sample purification or concentration) was never altered more than 3-fold compared with the results obtained in phosphate-buffered saline. PMID:22773632

  3. Finger-Actuated, Self-Contained Immunoassay Cassettes

    PubMed Central

    Qiu, Xianbo; Thompson, Jason A.; Chen, Zongyuan; Liu, Changchun; Chen, Dafeng; Ramprasad, Sudhir; Mauk, Michael G.; Ongagna, Serge; Barber, Cheryl; Abrams, William R.; Malamud, Daniel; Corstjens, Paul L.A.M.; Bau, Haim H.

    2010-01-01

    The building blocks for an inexpensive, disposable, luminescence-based microfluidic immunoassay cassette are described, and their integration in a point-of-care diagnostic system is demonstrated. Fluid motion in the cassette is driven by depressing finger-actuated pouches. All reagents needed for the immunoassay can be stored in the cassette in liquid form. Prior to use, the cassette consists of two separate parts. A top storage component contains pouches, sealed storage chambers, a metering chamber, and needle seats. The bottom processing component contains connection needles, a mixing chamber, and a detection chamber with immobilized proteins. Subsequent to sample introduction, the storage and processing components are mated. The needles form hydraulic connections between the two parts and, in some cases, close valves. The pouches are then actuated sequentially to induce flow of various reagents and facilitate process operations. The cassette is compatible with different detection modalities. Both a cassette with immunochromatographic-based detection and a cassette with microbead-based detection were constructed and evaluated. The immunochromatographic cassette was used to detect antibodies to HIV in saliva samples. The bead-based cassette was used to detect the proinflammatory chemokine IL-8. The experimental data demonstrates good repeatability and reasonable sensitivity. PMID:19597994

  4. Finger-actuated, self-contained immunoassay cassettes.

    PubMed

    Qiu, Xianbo; Thompson, Jason A; Chen, Zongyuan; Liu, Changchun; Chen, Dafeng; Ramprasad, Sudhir; Mauk, Michael G; Ongagna, Serge; Barber, Cheryl; Abrams, William R; Malamud, Daniel; Corstjens, Paul L A M; Bau, Haim H

    2009-12-01

    The building blocks for an inexpensive, disposable, luminescence-based microfluidic immunoassay cassette are described, and their integration in a point-of-care diagnostic system is demonstrated. Fluid motion in the cassette is driven by depressing finger-actuated pouches. All reagents needed for the immunoassay can be stored in the cassette in liquid form. Prior to use, the cassette consists of two separate parts. A top storage component contains pouches, sealed storage chambers, a metering chamber, and needle seats. The bottom processing component contains connection needles, a mixing chamber, and a detection chamber with immobilized proteins. Subsequent to sample introduction, the storage and processing components are mated. The needles form hydraulic connections between the two parts and, in some cases, close valves. The pouches are then actuated sequentially to induce flow of various reagents and facilitate process operations. The cassette is compatible with different detection modalities. Both a cassette with immunochromatographic-based detection and a cassette with microbead-based detection were constructed and evaluated. The immunochromatographic cassette was used to detect antibodies to HIV in saliva samples. The bead-based cassette was used to detect the proinflammatory chemokine IL-8. The experimental data demonstrates good repeatability and reasonable sensitivity. PMID:19597994

  5. Development of an Heterologous Immunoassay for Ciprofloxacin Residue in Milk

    NASA Astrophysics Data System (ADS)

    Jinqing, Jiang; Haitang, Zhang; Zhixing, An; Zhiyong, Xu; Xuefeng, Yang; Huaguo, Huang; Ziliang, Wang

    A heterologous immunoassay has been developed for the determination of Ciprofloxacin (CPFX) residues in milk. For this reason, carbodiimide active ester method was employed to synthesize the artificial antigen of CPFX-BSA, and mixed anhydride reaction was used to prepare the coating antigen of CPFX-OVA to pursue the heterologous sensitivity. Based on the square matrix titration, an icELISA method was developed for the quantitative detection of CPFX in cattle milk. The dynamic range was from 0.036 to 92.5 ng/mL, with LOD and IC50 value of 0.019 ng/mL and 1.8 ng/mL, respectively. Except for a high cross-reactivity (89.7%) to Enrofloxacin, negligible cross-reactivity to the other compounds was observed. After optimization, 0.03 mol/L of HCl, or 10% of methanol was used in the assay buffer. 20-fold dilution in cattle milk gave an inhibition curve almost the same as that in PBS buffer. The regression equation for this assay was y = 0.9036 x + 1.4574, with a correlation coefficient (R2) of 0.9844. The results suggest the veracity of the heterologous immunoassay for detecting CPFX residue in milk.

  6. Quantum-Dots Based Electrochemical Immunoassay of Interleukin-1?

    SciTech Connect

    Wu, Hong; Liu, Guodong; Wang, Jun; Lin, Yuehe

    2007-07-01

    We describe a quantum-dot (QD, CdSe@ZnS)-based electrochemical immunoassay to detect a protein biomarker, interleukin-1? (IL-1?). QD conjugated with anti-IL-1? antibody was used as a label in an immunorecognition event. After a complete sandwich immunoreaction among the primary IL-1? antibody (immobilized on the avidin-modified magnetic beads), IL-1?, and the QD-labeled secondary antibody, QD labels were attached to the magnetic-bead surface through the antibody-antigen immunocomplex. Electrochemical stripping analysis of the captured QDs was used to quantify the concentration of IL-1? after an acid-dissolution step. The streptavidin-modified magnetic beads and the magnetic separation platform were used to integrate a facile antibody immobilization (through a biotin/streptavidin interaction) with immunoreactions and the isolation of immunocomplexes from reaction solutions in the assay. The voltammetric response is highly linear over the range of 0.5 to 50 ng mL-1 IL 1?, and the limit of detection is estimated to be 0.3 ng mL-1 (18 pM). This QD-based electrochemical immunoassay shows great promise for rapid, simple, and cost-effective analysis of protein biomarkers.

  7. Sensitive Immunoassays of Nitrated Fibrinogen in Human Biofluids

    SciTech Connect

    Tang, Zhiwen; Wu, Hong; Du, Dan; Wang, Jun; Wang, Hua; Qian, Weijun; Bigelow, Diana J.; Pounds, Joel G.; Smith, Richard D.; Lin, Yuehe

    2010-05-05

    Three new sandwich immunoassays for detection of nitrated biomarker have been established with potential applications in biomedical studies and clinical practice. In this study, nitrated human fibrinogen, a potential oxidative stress biomarker for several pathologies, was chosen as the target. To improve the sensitivity and overcome the interference caused by the complexity of human biofluids, we developed three sandwich strategies using various combinations of primary antibody and secondary antibody. All three strategies demonstrated high sensitivity and selectivity towards nitrated forms of fibrinogen in buffer, but their performances were dramatically reduced when tested with human plasma and serum samples. Systematically optimizations were carried out to investigate the effects of numerous factors, including sampling, coating, blocking, and immunoreactions. Our final optimization results indicate that two of these strategies retain sufficient sensitivity and selectivity for use as assays in human physiological samples. Specifically, detection limits reached the pM level and the linear response ranges were up to nM level with a correlation coefficient > 0.99. To our best knowledge, this is the first example of using an electrochemical immunoassay for a nitrated biomarker in a physiological fluid. This novel approach provides a rapid, sensitive, selective, cost efficient and robust bioassay for detection of oxidative stress in pathology and for clinical applications. Moreover, the sandwich strategies developed in this paper can be readily used to establish effective methods targeting other nitration biomarkers.

  8. Oocyte cryopreservation for donor egg banking.

    PubMed

    Cobo, Ana; Remohí, José; Chang, Ching-Chien; Nagy, Zsolt Peter

    2011-09-01

    Oocyte donation is an efficient alternative to using own oocytes in IVF treatment for different indications. Unfortunately, 'traditional' (fresh) egg donations are challenged with inefficiency, difficulties of synchronization, very long waiting periods and lack of quarantine measures. Given the recent improvements in the efficiency of oocyte cryopreservation, it is reasonable to examine if egg donation through oocyte cryopreservation has merits. The objective of the current manuscript is to review existing literature on this topic and to report on the most recent outcomes from two established donor cryobank centres. Reports on egg donation using slow freezing are scarce and though results are encouraging, outcomes are not yet comparable to a fresh egg donation treatment. Vitrification on the other hand appears to provide high survival rates (90%) of donor oocytes and comparable fertilization, embryo development, implantation and pregnancy rates to traditional (fresh) egg donation. Besides the excellent outcomes, the ease of use for both donors and recipients, higher efficiency, lower cost and avoiding the problem of synchronization are all features associated with the benefit of a donor egg cryobank and makes it likely that this approach becomes the future standard of care. Oocyte donation is one of the last resorts in IVF treatment for couples challenged with infertility problems. However, traditional (fresh) egg donation, as it is performed today, is not very efficient, as typically all eggs from one donor are given to only one recipient, it is arduous as it requires an excellent synchronization between the donor and recipient and there are months or years of waiting time. Because of the development of an efficient oocyte cryopreservation technique, it is now possible to cryo-store donor (as well as non-donor) eggs, maintaining their viability and allowing their use whenever there is demand. Therefore, creating a donor oocyte cryobank would carry many advantages. In the present manuscript, the current experience with oocyte donation using cryopreservation technology is reviewed. The outcomes of two recently established donor egg cryobanks at Instituto Valenciano de Infertilidad in Spain and Reproductive Biology Associates in the USA (involving a large number of cases) demonstrate that egg cryo-survival is high and that fertilization, embryo development, implantation and pregnancy rates are similar to those reported after fresh egg donation. It also provides additional advantages of being more efficient, more economical, easier for both donors and recipients and potentially also safer, because eggs can now be quarantined for 6 months (or longer) to retest for infectious diseases in the donors. It is the opinion of the authors, based on several advantages associated with the use of donor egg cryobanking, that in the future there will be fewer traditional egg donations and increasingly more cryo-egg donations. PMID:21767989

  9. 21 CFR 640.31 - Suitability of donors.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma § 640.31 Suitability of donors. (a) Whole blood donors shall meet the criteria for donor suitability prescribed...

  10. 21 CFR 640.31 - Suitability of donors.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma § 640.31 Suitability of donors. (a) Whole blood donors shall meet the criteria for donor suitability prescribed...

  11. 21 CFR 640.31 - Suitability of donors.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma § 640.31 Suitability of donors. (a) Whole blood donors shall meet the criteria for donor suitability prescribed...

  12. 21 CFR 640.31 - Suitability of donors.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma § 640.31 Suitability of donors. (a) Whole blood donors shall meet the criteria for donor suitability prescribed...

  13. 21 CFR 640.31 - Suitability of donors.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma § 640.31 Suitability of donors. (a) Whole blood donors shall meet the criteria for donor suitability prescribed...

  14. 21 CFR 640.12 - Suitability of donor.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.12 Suitability of donor. The source blood for Red Blood Cells shall be obtained from a donor who meets the criteria for donor suitability...

  15. 21 CFR 660.31 - Suitability of the donor.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.31 Suitability of the donor. Donors of peripheral blood for Reagent Red Blood Cells shall meet the criteria for donor suitability...

  16. Donor Research in Australia: Challenges and Promise

    PubMed Central

    Masser, Barbara; Smith, Geoff; Williams, Lisa A.

    2014-01-01

    Summary Donors are the key to the core business of Blood Collection Agencies (BCAs). However, historically, they have not been a focus of research undertaken by these organizations. This model is now changing, with significant donor research groups established in a number of countries, including Australia. Donor research in the Australian Red Cross Blood Service (Blood Service) is concentrated in the Donor and Community Research (DCR) team. Cognizant of the complex and ever-changing landscape with regard to optimal donor management, the DCR team collaborates with academics located at universities around Australia to coordinate a broad program of research that addresses both short- and-long term challenges to the blood supply. This type of collaboration is not, however, without challenges. Two major collaborative programs of the Blood Service's research, focusing on i) the recruitment and retention of plasmapheresis donors and ii) the role of the emotion pride in donor motivation and return, are showcased to elucidate how the challenges of conducting collaborative BCA research can be met. In so doing, these and the other research programs described herein demonstrate how the Blood Service supports and contributes to research that not only revises operational procedures but also contributes to advances in basic science. PMID:25254025

  17. Donor deactivation in silicon nanostructures.

    PubMed

    Björk, Mikael T; Schmid, Heinz; Knoch, Joachim; Riel, Heike; Riess, Walter

    2009-02-01

    The operation of electronic devices relies on the density of free charge carriers available in the semiconductor; in most semiconductor devices this density is controlled by the addition of doping atoms. As dimensions are scaled down to achieve economic and performance benefits, the presence of interfaces and materials adjacent to the semiconductor will become more important and will eventually completely determine the electronic properties of the device. To sustain further improvements in performance, novel field-effect transistor architectures, such as FinFETs and nanowire field-effect transistors, have been proposed as replacements for the planar devices used today, and also for applications in biosensing and power generation. The successful operation of such devices will depend on our ability to precisely control the location and number of active impurity atoms in the host semiconductor during the fabrication process. Here, we demonstrate that the free carrier density in semiconductor nanowires is dependent on the size of the nanowires. By measuring the electrical conduction of doped silicon nanowires as a function of nanowire radius, temperature and dielectric surrounding, we show that the donor ionization energy increases with decreasing nanowire radius, and that it profoundly modifies the attainable free carrier density at values of the radius much larger than those at which quantum and dopant surface segregation effects set in. At a nanowire radius of 15 nm the carrier density is already 50% lower than in bulk silicon due to the dielectric mismatch between the conducting channel and its surroundings. PMID:19197312

  18. Europium Nanoparticle-Based High Performing Immunoassay for the Screening of Treponemal Antibodies

    PubMed Central

    Talha, Sheikh M.; Hytönen, Jukka; Westhorpe, Adam; Kumar, Sushil; Khanna, Navin; Pettersson, Kim

    2013-01-01

    Treponema pallidum subspecies pallidum (Tp) is the causative agent of syphilis which mainly spreads through sexual contact, blood transfusion and perinatal route. In order to curtail the spread of the infection and to clinically manage the disease, timely, accurate and reliable diagnosis is very important. We have developed an immunoassay for the detection of treponemal antibodies in human serum or plasma samples. In vivo biotinylated and non-biotinylated versions of the recombinant antigen were designed by the fusion of three Tp-specific antigens namely Tp15, Tp17 and Tp47. These fusion antigens were expressed in E. coli and purified using single-step metal affinity chromatography. Biotinylated fusion antigen immobilized on streptavidin coated plate was used to capture the treponemal antibodies and the non-biotinylated antigen coated on europium nanoparticles was used as tracer. Assays with two different incubation times of 10 min and 1 h were developed, and following the incubation the europium fluorescence was measured using time-resolved fluorometry. The developed time-resolved fluorometric (TRF) immunoassays were evaluated with in-house and commercial serum/plasma sample panels. For well-established treponemal antibodies positive or negative samples, the sensitivity of TRF immunoassay with 10 min incubation time was 97.4%, and of TRF immunoassay with 1 h incubation time was 98.7%, and the specificities of both the TRF immunoassays were 99.2%. For the samples with discordant results with the reference assays, both the TRF immunoassays showed better specificity than the Enzygnost syphilis enzyme immunoassay as a screening test. The two different incubation times did not have any significant effect on the signal to cutoff (S/Co) ratios obtained with the two immunoassays (p?=?0.06). Our results indicate that the developed immunoassay with a short incubation time of 10 min has the potential to be used in clinical laboratories and in blood-bank settings as a screening test for treponemal antibodies. PMID:24386329

  19. Psychosocial Assessment of Living Organ Donors: Clinical and Ethical Considerations

    Microsoft Academic Search

    Mary Ellen Olbrisch; Sharon M. Benedict

    2001-01-01

    This article outlines psychosocial and ethical issues to be considered when evaluating potential living organ donors. Six types of living donors are described: genetically related, emotionally related, \\

  20. Interventional radiology in living donor liver transplant

    PubMed Central

    Cheng, Yu-Fan; Ou, Hsin-You; Yu, Chun-Yen; Tsang, Leo Leung-Chit; Huang, Tung-Liang; Chen, Tai-Yi; Hsu, Hsien-Wen; Concerjero, Allan M; Wang, Chih-Chi; Wang, Shih-Ho; Lin, Tsan-Shiun; Liu, Yueh-Wei; Yong, Chee-Chien; Lin, Yu-Hung; Lin, Chih-Che; Chiu, King-Wah; Jawan, Bruno; Eng, Hock-Liew; Chen, Chao-Long

    2014-01-01

    The shortage of deceased donor liver grafts led to the use of living donor liver transplant (LDLT). Patients who undergo LDLT have a higher risk of complications than those who undergo deceased donor liver transplantation (LT). Interventional radiology has acquired a key role in every LT program by treating the majority of vascular and non-vascular post-transplant complications, improving graft and patient survival and avoiding, in the majority of cases, surgical revision and/or re-transplant. The aim of this paper is to review indications, diagnostic modalities, technical considerations, achievements and potential complications of interventional radiology procedures after LDLT. PMID:24876742

  1. Current research on organ donor management.

    PubMed

    Sally, Mitchell; Malinoski, Darren

    2013-12-01

    A shortage of organs is available for transplantation, with 116,000 patients on the Organ Procurement and Transplantation Network/United Network for Organ Sharing wait list. Because the demand for organs outweighs the supply, considerable care must be taken to maximize the number of organs transplanted per donor and optimize the quality of recovered organs. Studies designed to determine optimal donor management therapies are limited, and this research has many challenges. Although evidenced-based guidelines for managing potential organ donors do not exist, research in this area is increasing. This article reviews the existing literature and highlights recent trials that can guide management. PMID:24287350

  2. Is right laparoscopic donor nephrectomy right?

    Microsoft Academic Search

    Mark Sawatzky; Abdulmalik Altaf; James Ellsmere; Dennis Klassen; Mark Walsh; Michele Molinari; Björn Nashan; Jaap Bonjer

    2009-01-01

    Introduction  Laparoscopic donor nephrectomy has become the standard of care in many renal transplant centers. Many centers are reluctant\\u000a to perform right laparoscopic donor nephrectomies, primarily due to concerns about transplanting a kidney with a short renal\\u000a vein.\\u000a \\u000a \\u000a \\u000a Methods  A retrospective review of 26 right and 24 left consecutive donor nephrectomies and their recipients was performed. Patient\\u000a demographics, preoperative, perioperative, and postoperative

  3. Fluorescence immunoassay of octachlorostyrene based on Förster resonance energy transfer between CdTe quantum dots and rhodamine B.

    PubMed

    Wang, Xin; Sheng, Pengtao; Zhou, Liping; Tong, Xi; Shi, Lei; Cai, Qingyun

    2014-10-15

    Octachlorostyrene (OCS), a persistent and bioaccumulative toxicant (PBT), was assayed by fluorescence immunoassay based on the Förster resonance energy transfer (FRET) between CdTe quantum dots (QDs) and rhodamine B-labeled OCS (RB-OCS). Anti-OCS antibody produced in this lab is adsorbed on a microtiter plate. The RB-OCS competes with OCS for the highly specific immunoreaction with the anti-OCS antibodies adsorbed on the microtiter plate. The solution is then isolated and mixed with CdTe QDs as fluorescent donor which excite the emission of RB-OCS through FRET. As a result, the emission of CdTe QDs at 530 nm decreases, whereas the emission of RB-OCS at 580 nm increases. The ratio of fluorescence intensity at 580 nm to that at 530 nm is proportional to the RB-OCS concentration at a fixed CdTe QDs concentration, and consequently proportional to the OCS concentration. Selective and sensitive responses to OCS are achieved with a linear range of 8-80 nM and a LOD of 3.8 nM. Because OCS is quantified based on the fluorescence ratio, the sensor-to-sensor difference is greatly eliminated, making the proposed method a useful approach for in site scanning of OCS. PMID:24768862

  4. Donor Hearts Going to Waste, Researchers Report

    MedlinePLUS

    ... professor of cardiology at the University of California, Los Angeles. "Unfortunately, there is a severe shortage of donor ... Heart Association, and professor, cardiology, University of California, Los Angeles; Feb. 10, 2015, statement, American Society of Transplantation; ...

  5. Bacterial Magnetic Nanoparticles as Peroxidase Mimetics and Application in Immunoassay

    NASA Astrophysics Data System (ADS)

    Hu, Lili; Song, Tao; Ma, Qiufeng; Chen, Chuanfang; Pan, Weidong; Xie, Chunlan; Nie, Leng; Yang, Wenhui

    2010-12-01

    Although progress in nanosynthesis has succeeded in making nanoscale particles from iron oxide, the research about natural magnetic nanoparticles, magnetosomes, is still a current interest because of their intrinsic magnetic features, nano-features, membrane-enclosed features and genetic control of size and morphology properties. In this study, we investigated magnetosomes' intrinsic peroxidase-like activity similar to that found in artificial magnetic nanoparticles. We characterized the catalytic activity by varying the method of extraction and storage, the pH value, the temperature and the H2O2 concentration. Based on these finding, we developed a simplified immunoassay approach to use magnetosomes as a peroxidase mimic catalyst and a magnetic separator as well.

  6. On-Chip Immunoassay for Determination of Urinary Albumin

    PubMed Central

    Laiwattanapaisal, Wanida; Songjaroen, Temsiri; Maturos, Thitima; Lomas, Tanom; Sappat, Assawapong; Tuantranont, Adisorn

    2009-01-01

    An immunoassay performed on a portable microfluidic device was evaluated for the determination of urinary albumin. An increase in absorbance at 500 nm resulting from immunoagglutination was monitored directly on the poly(dimethylsiloxane) (PDMS) microchip using a portable miniature fibre-optic spectrometer. A calibration curve was linear up to 10 mg L–1 (r2 = 0.993), with a detection limit of 0.81 mg L–1 (S/N = 3). The proposed system showed good precision, with relative standard deviations (RSDs) of 5.1%, when evaluated with 10 mg L–1 albumin (n = 10). Determination of urinary albumin with the proposed system gave results highly similar to those determined by the conventional spectrophotometric method using immunoturbidimetric detection (r2 = 0.995; n = 15). PMID:22303162

  7. Development of an ultrasensitive immunoassay for detecting tartrazine.

    PubMed

    Li, Zhuokun; Song, Shanshan; Xu, Liguang; Kuang, Hua; Guo, Shidong; Xu, Chuanlai

    2013-01-01

    We have developed an ultrasensitive indirect competitive enzyme-linked immunosorbent assay for the determination of tartrazine. Two carboxylated analogues of tartrazine with different spacer lengths, and one derivative from commercial tartrazine after a little chemical modification, were synthesized as haptens in order to produce antibodies specific to tartrazine. The effect of sulfonic acid groups on the hapten structure of tartrazine was also studied carefully for the first time. A most specific monoclonal antibody against tartrazine was created and exhibited an IC50 value of 0.105 ng/mL and a limit of detection of 0.014 ng/mL, with no cross-reactivity to other structurally-related pigments. The established immunoassay was applied to the determination of tartrazine in fortified samples of orange juice and in real positive samples of carbonated beverages. PMID:23799494

  8. Gold bands as a suitable surface for enzyme immunoassays.

    PubMed

    Abad-Villar, Eva M; Fernández-Abedul, M Teresa; Costa-García, Agustín

    2002-09-01

    Gold bands sputtered over a polymeric material, Kapton, are employed for the development of enzyme immunoassays. The immunological interaction takes place between human IgM and alkaline phosphatase (AP) conjugated anti-IgM. The model analyte (IgM) could be determined following a non-competitive design in the range of 0.05-5 ppm, with a limit of detection of 50 ppb. After the interaction, gold bands are sequentially inserted in a flow system and the extension of the reaction is followed through the enzymatic hydrolysis of naphthylphosphate, AP substrate. The product, naphthol, is oxidised to naphtoquinone in the gold band of the flow cell that constitutes the detector. Parameters affecting the interaction are studied and calibration curves are performed. The reproducibility between different bands (RSD=4%, n=5) and possibilities of regeneration are also detailed. PMID:12191928

  9. Polycarbazole-based organic photodiodes for highly sensitive chemiluminescent immunoassays.

    PubMed

    Pires, Nuno M M; Dong, Tao

    2013-01-01

    It is reported the development of a polycarbazole-based organic photodetector for chemiluminescent immunoassays. The optical detector comprised a 1?4 blend by weight of poly [N-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT) and [6,6]-phenyl C71-butyric acid methyl ester (PC70BM). Optimization of the photodetector design was conducted aiming to maximize photosensitivity and reduce the background level. Quantitation of recombinant human thyroid stimulating hormone indicated good linearity and yielded a detection sensitivity of ?3.7 nA × nM(-1) and a detection limit of 80 pg/ml. PMID:24110033

  10. Development of an Ultrasensitive Immunoassay for Detecting Tartrazine

    PubMed Central

    Li, Zhuokun; Song, Shanshan; Xu, Liguang; Kuang, Hua; Guo, Shidong; Xu, Chuanlai

    2013-01-01

    We have developed an ultrasensitive indirect competitive enzyme-linked immunosorbent assay for the determination of tartrazine. Two carboxylated analogues of tartrazine with different spacer lengths, and one derivative from commercial tartrazine after a little chemical modification, were synthesized as haptens in order to produce antibodies specific to tartrazine. The effect of sulfonic acid groups on the hapten structure of tartrazine was also studied carefully for the first time. A most specific monoclonal antibody against tartrazine was created and exhibited an IC50 value of 0.105 ng/mL and a limit of detection of 0.014 ng/mL, with no cross-reactivity to other structurally-related pigments. The established immunoassay was applied to the determination of tartrazine in fortified samples of orange juice and in real positive samples of carbonated beverages. PMID:23799494

  11. Performance of immunoassay kits for site characterization and remediation

    SciTech Connect

    Waters, L.C.; Palausky, A.; Counts, R.W.; Jenkins, R.A.

    1995-12-31

    The US Department of Energy (DOE) is supporting efforts to identify, validate and implement the use of effective, low-cost alternatives to currently used analytical methods for environmental management. As part of that program, we have evaluated the performances of a number of immunoassay (IA) kits with specificities for environmental contaminants of concern to the DOE. The studies were done in the laboratory using both spiked and field test samples. The analyte specificity and manufacturers of the kits evaluated were the following: mercury, BioNebraska; polychlorinated biphenyls (PCBs), EnSys and Millipore; petroleum fuel hydrocarbons, Millipore and Ohmicron; and polyaromatic hydrocarbons (PAHs), Ohmicron and Millipore. The kits were used in either a semiquantitative or quantitative format according to the preference of the manufacturers.

  12. Immunoassay for the quantitation of human leukocyte interferon.

    PubMed

    Berthold, W; Merk, W; Adolf, G R

    1985-01-01

    A sensitive nonradioactive immunoassay based on monoclonal antibodies was developed. A number of monoclonal hybridomas secreting antibodies against human leukocyte interferon (IFN alpha) were generated using mice immunized with purified lymphoblastoid IFN. Although the binding of antibody to IFN alpha was used as one criterium of selection, all antibodies found can neutralize its antiviral activity. A pair of antibodies binding to different regions of IFN alpha was identified. These were incorporated into sensitive sandwich assays of IFN alpha. A microtiter plate assay - using horse radish peroxidase as marker enzyme - is able to detect IFN alpha at a concentration of 30 IU/ml within 5 h. An overnight tube assay can detect approximately 30 pg IFN alpha 2 or 3 IU per ml solution. The 5-h ELISA (enzyme-linked immunosorbent assay) is well suited for the monitoring of the recovery of rIFN alpha from recombinant organism, during purification and refinement of the protein to a therapeutic drug. PMID:4039175

  13. Organ Transplants from Living Donors – Halachic Aspects*

    PubMed Central

    Halperin, Mordechai

    2011-01-01

    This manuscript is a survey of the halachic attitudes toward organ transplant procedures from a living donor which can be defined as life-saving procedures for the recipient or at least life-prolonging procedures. Three fundamental problems concerning the halachic aspects of such transplantation are discussed in detail: the danger to the donor, donation under coercion, and the sale of organs and tissues. The terms “halacha” and “Jewish law” are defined in the introduction. PMID:23908800

  14. Comparative study of donor lung injury in heart-beating versus non-heart-beating donors

    Microsoft Academic Search

    Arne P. Neyrinck; Caroline Van De Wauwer; Nele Geudens; Filip R. Rega; Geert M. Verleden; Patrick Wouters; Toni E. Lerut; Dirk E. M. Van Raemdonck

    2006-01-01

    Objective: The use of non-heart-beating donors (NHBD) has been advocated as an alternative to overcome the critical organ shortage in lung transplantation despite the warm ischemic period that may result in primary graft dysfunction. On the contrary, brain death in the heart-beating donor (HBD) may be an underestimated risk factor for donor lung injury. We postulated that 60min of warm

  15. Development of immunoassays for biomonitoring of hexamethylene diisocyanate exposure.

    PubMed Central

    Lemus, R; Lukinskeine, L; Bier, M E; Wisnewski, A V; Redlich, C A; Karol, M H

    2001-01-01

    Hexamethylene diisocyanate (HDI) is used widely to manufacture polyurethanes for paints and coatings. It is an irritant and a chemical asthmagen. The U.S. Occupational Safety and Health Administration time-weighted average permissible exposure limit is 5 ppb and the ceiling limit is 20 ppb. We sought to develop a sensitive and specific immuno-bioassay to supplement workplace air monitoring and detect recent HDI exposure. For this, we produced rabbit antiserum to HDI-adducted keyhole limpet hemocyanin (HDI-KLH). The specificity of the antiserum was demonstrated by its reaction with a variety of HDI-conjugated proteins and the absence of reactions with conjugates of other diisocyanates, namely toluene diisocyanate and diphenyl methylene diisocyanate. Four immunoassays were developed and compared for their ability to detect decreasing quantities of HDI-adducted human serum albumin (HSA) containing 2 mol HDI adduct per mol HSA (HDI(2)-HSA) as determined by matrix-assisted laser desorption time-of-flight (MALDI-TOF) mass spectrometry. The sensitivities of some of the assays are within the range (0.82-45 nM) of current analytic methods. A Western analysis procedure has a sensitivity of 600 nM HDI adduct on HSA. ELISA inhibition assay, in which microtiter plates are coated with the HDI(2)-HSA antigen, has a sensitivity of 300 nM HDI adduct. An immunoblot assay has a sensitivity of 9 nM HDI adduct. The most sensitive bioassay (1.8 nM HDI adduct) is a three-antibody sandwich ELISA in which wells of microtiter plates are coated with the IgG fraction of the anti-HDI-KLH antisera. Compared with analytic methods for HDI biomonitoring, the immunoassays are faster and less costly and accommodate numerous samples simultaneously. The assays have the potential to affect industrial biomonitoring programs significantly. PMID:11712993

  16. The development of immunoassays for detection of chemical warfare agents

    SciTech Connect

    Lenz, D.E.; Brimfield, A.A.; Cook, L. [Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD (United States)

    1996-10-01

    With the advent of enzyme linked immunoabsorbent assays (ELISA) and monoclonal antibodies in the last two decades, there has been considerable effort devoted to the development of antibodies to detect and quantify low molecular weight toxic substances in environmental or biological fluids. Polyclonal antibodies against paraoxon (the toxic metabolite of parathion) were capable of detecting paraoxon in body fluids at a level of 10{sup -9} M ({approximately}260 pg/mL) when used in a competitive inhibition enzyme immunoassay (CIEIA). Monoclonal antibodies developed against a structural analogue of the chemical warfare agent soman were capable of detection soman in buffer solutions at a level of 10{sup -6} M ({approximately}180 ng/mL). In addition these antibodies were found to be highly specific for soman even in the presence of its major hydrolysis product. Subsequent studies with antisoman monoclonal antibodies extended the level of sensitivity to {approximately}80 ng/mL. Furthermore these antibodies did not cross react with other chemical warfare nerve agents such as sarin or tabun. In all cases, the time for a confirmatory test was two hours or less. Immunoassays for T-2 micotoxins have also been reported with a minimal detection range of 2 pg/assay to 50 ng/assay for the polyclonal and monoclonal T-2 antibodies respectively. These reagents offer a sensitive, rapid and low cost approach to the diagnosis or detection of the presence of toxic chemical substances. More recent efforts have focussed on developing antibodies specific for sulfur mustard a highly reactive vesicating agent.

  17. Systemic Heparinisation in Laparoscopic Live Donor Nephrectomy

    PubMed Central

    Hosgood, Sarah A.; Nicholson, Michael L.

    2013-01-01

    Introduction. Systemic heparinisation is advocated during laparoscopic live donor nephrectomy (LDN) as a preventative measure against renal vascular thrombosis during the warm ischaemic interval. This study compares the outcome with and without the administration of systemic heparinisation. Methods. A retrospective analysis was performed on 186 consecutive LDN patients between April 2008 and November 2012. Systemic heparin (2000–3000?IU) was administered intravenously to donors (hep n = 109). From January 2010, heparin was not used systemically in this group of LDN (no hep n = 77). Outcome measures included donor and recipient complications, initial graft function, and 12 month graft survival. Results. The demographics of both heparinised and non-heparinised donors were similar. The warm ischaemic time (WIT) was comparable in both groups (WIT; hep 5 ± 3 versus no hep 5 ± 3 minutes; P = 1.000). There was no difference in complication rates, no episodes of graft thrombosis, and no incidences of primary nonfunction in either group. Delayed graft function occurred in 4/109 and 1/77 (3.6% versus 1.2%; P = 0.405) and there was no significant difference in graft survival (P = 0.650). Conclusion. Omitting systemic heparinisation during laparoscopic donor nephrectomy is a feasible and safe approach that does not compromise donor or recipient outcome. PMID:24455192

  18. Selecting suitable solid organ transplant donors: Reducing the risk of donor-transmitted infections

    PubMed Central

    Jr, Christopher S Kovacs; Koval, Christine E; van Duin, David; de Morais, Amanda Guedes; Gonzalez, Blanca E; Avery, Robin K; Mawhorter, Steven D; Brizendine, Kyle D; Cober, Eric D; Miranda, Cyndee; Shrestha, Rabin K; Teixeira, Lucileia; Mossad, Sherif B

    2014-01-01

    Selection of the appropriate donor is essential to a successful allograft recipient outcome for solid organ transplantation. Multiple infectious diseases have been transmitted from the donor to the recipient via transplantation. Donor-transmitted infections cause increased morbidity and mortality to the recipient. In recent years, a series of high-profile transmissions of infections have occurred in organ recipients prompting increased attention on the process of improving the selection of an appropriate donor that balances the shortage of needed allografts with an approach that mitigates the risk of donor-transmitted infection to the recipient. Important advances focused on improving donor screening diagnostics, using previously excluded high-risk donors, and individualizing the selection of allografts to recipients based on their prior infection history are serving to increase the donor pool and improve outcomes after transplant. This article serves to review the relevant literature surrounding this topic and to provide a suggested approach to the selection of an appropriate solid organ transplant donor. PMID:25032095

  19. Development of Sensitive Immunoassays for the Detection of the Glucuronide Conjugate of 3-Phenoxybenzyl Alcohol, a

    E-print Network

    Hammock, Bruce D.

    affected by pH 4-9. A 5-fold improvement in IC50 was observed using a 10-fold concentrated phosphate, respectively) was observed between spiked levels and the levels detected by the immunoassay. KEYWORDS: ELISA

  20. Immunoassay Techniques for Detection of the Herbicide Simazine Based on Use of Oppositely

    E-print Network

    Hammock, Bruce D.

    Immunoassay Techniques for Detection of the Herbicide Simazine Based on Use of Oppositely Charged to an assay for the herbicide simazine. Both enzyme-linked immu- nosorbent assay (ELISA) and dot blot formats

  1. Development of an integrated capillary valve-based preconcentrator and surface-based immunoassay

    E-print Network

    Liu, Vincent Hok

    2009-01-01

    A new generation of integrated preconcentrator and immunoassay was developed. A novel, self-aligned method for patterning Nafion resin was developed and applied to create a preconcentrator. In a parallel effort, a surface-based ...

  2. A sensitive rapid on-site immunoassay for heavy metal contamination

    SciTech Connect

    Blake, R.; Blake, D.; Flowers, G.

    1996-05-02

    This project concerns the development of immunoassays for heavy metals that will permit the rapid on-site analysis of specific heavy metals, including lead and chromium in water and soil samples. 2 refs.

  3. An Inexpensive, Fast and Sensitive Quantitative Lateral Flow Magneto-Immunoassay for Total Prostate Specific Antigen

    PubMed Central

    Barnett, Jacqueline M.; Wraith, Patrick; Kiely, Janice; Persad, Raj; Hurley, Katrina; Hawkins, Peter; Luxton, Richard

    2014-01-01

    We describe the detection characteristics of a device the Resonant Coil Magnetometer (RCM) to quantify paramagnetic particles (PMPs) in immunochromatographic (lateral flow) assays. Lateral flow assays were developed using PMPs for the measurement of total prostate specific antigen (PSA) in serum samples. A detection limit of 0.8 ng/mL was achieved for total PSA using the RCM and is at clinically significant concentrations. Comparison of data obtained in a pilot study from the analysis of serum samples with commercially available immunoassays shows good agreement. The development of a quantitative magneto-immunoassay in lateral flow format for total PSA suggests the potential of the RCM to operate with many immunoassay formats. The RCM has the potential to be modified to quantify multiple analytes in this format. This research shows promise for the development of an inexpensive device capable of quantifying multiple analytes at the point-of-care using a magneto-immunoassay in lateral flow format. PMID:25587419

  4. Normalization and Statistical Analysis of Multiplexed Bead-Based Immunoassay Data Using Mixed-Effects Modeling

    E-print Network

    Clarke, David C.

    Multiplexed bead-based flow cytometric immunoassays are a powerful experimental tool for investigating cellular communication networks, yet their widespread adoption is limited in part by challenges in robust quantitative ...

  5. Detection of borna disease virus-reactive antibodies from patients with psychiatric disorders and from horses by electrochemiluminescence immunoassay.

    PubMed

    Yamaguchi, K; Sawada, T; Naraki, T; Igata-Yi, R; Shiraki, H; Horii, Y; Ishii, T; Ikeda, K; Asou, N; Okabe, H; Mochizuki, M; Takahashi, K; Yamada, S; Kubo, K; Yashiki, S; Waltrip, R W; Carbone, K M

    1999-09-01

    The prevalence of Borna disease virus (BDV)-specific antibodies among patients with psychiatric disorders and healthy individuals has varied in several reports using several different serological assay methods. A reliable and specific method for anti-BDV antibodies needs to be developed to clarify the pathological significance of BDV infections in humans. We developed a new electrochemiluminescence immunoassay (ECLIA) for the antibody to BDV that uses two recombinant proteins of BDV, p40 and p24 (full length). Using this ECLIA, we examined 3,476 serum samples from humans with various diseases and 917 sera from blood donors in Japan for the presence of anti-BDV antibodies. By ECLIA, 26 (3.08%) of 845 schizophrenia patients and 9 (3.59%) of 251 patients with mood disorders were seropositive for BDV. Among 323 patients with other psychiatric diseases, 114 with neurological diseases, 75 with chronic fatigue syndrome, 85 human immunodeficiency virus-infected patients, 50 with autoimmune diseases including rheumatoid arthritis and systemic lupus erythematosis and 17 with leprosy, there was no positive case except one case each with alcohol addiction, AIDS, and dementia. Although 19 (1.36%) of 1,393 patients with various ocular diseases, 10 (1.09%) of 917 blood donors, and 3 (4.55%) of 66 multitransfused patients were seropositive for BDV-specific antigen, high levels of seroprevalence in schizophrenia patients and young patients (16 to 59 years old) with mood disorders were statistically significant. The immunoreactivity of seropositive sera could be verified for specificity by blocking with soluble p40 and/or p24 recombinant protein. Anti-p24 antibody was more frequent than p40 antibody in most cases, and in some psychotic patients antibody profiles showed only p40 antibody. Although serum positive for both p40 and p24 antibodies was not found in this study, the p40 ECLIA count in schizophrenia patients was higher than that of blood donors. Furthermore, we examined 90 sera from Japanese feral horses. Antibody profiles of control human samples are similar to that of naturally BDV-infected feral horses. We concluded that BDV infection was associated in some way with psychiatric disorders. PMID:10473520

  6. Fluorescence polarization immunoassays and related methods for simple, high-throughput screening of small molecules

    Microsoft Academic Search

    David S. Smith; Sergei A. Eremin

    2008-01-01

    Fluorescence polarization immunoassay (FPIA) is a homogeneous (without separation) competitive immunoassay method based on\\u000a the increase in fluorescence polarization (FP) of fluorescent-labeled small antigens when bound by specific antibody. The\\u000a minimum detectable quantity of FPIAs with fluorescein label (about 0.1 ng analyte) is comparable with chromatography and ELISA\\u000a methods, although this may be limited by sample matrix interference. Because of its

  7. Enhanced solid-phase immunoassay using gold nanoshells: effect of nanoparticle optical properties

    Microsoft Academic Search

    Boris Khlebtsov; Nikolai Khlebtsov

    2008-01-01

    Plasmon-resonant nanoparticle-labeled immunoassays provide a simple, low-cost and effective way of detecting target molecules in solutions. The optical mechanisms behind their efficiency, however, have not been addressed until now. We present the first theoretical description of nanoparticle-labeled dot immunoassay and its experimental verification with functionalized 15 nm colloidal gold nanospheres and silica\\/gold nanoshells (GNs). Three types of GNs, with silica

  8. Rapid homogeneous immunoassay of peptides based on bioluminescence resonance energy transfer from firefly luciferase

    Microsoft Academic Search

    Yukari Yamakawa; Hiroshi Veda; Atsushi Kitayama; Teruyuki Nagamune

    2002-01-01

    A sensitive homogeneous immunoassay is needed in the field of clinical diagnostics. Here we propose a rapid and potentially sensitive homogeneous immunoassay of peptide epitope based on the bioluminescence resonance energy transfer (BRET). A GST peptide tag fused to the N-terminus of firefly luciferase, and Cy3 or Cy3.5-labeled anti-peptide antibody were prepared to detect BRET from the hybrid luciferase to

  9. Demonstration of a Homogeneous Noncompetitive Immunoassay Based on Bioluminescence Resonance Energy Transfer

    Microsoft Academic Search

    Ryoichi Arai; Hideyuki Nakagawa; Kouhei Tsumoto; Walt Mahoney; Izumi Kumagai; Hiroshi Ueda; Teruyuki Nagamune

    2001-01-01

    We describe a noncompetitive homogeneous bioluminescent immunoassay based on the antigen-dependent reassociation of antibody variable domains (open sandwich bioluminescent immunoassay, OS-BLIA). The reassociation of two chimeric proteins, an antibody heavy-chain fragment (VH)–Renilla luciferase (Rluc) and an antibody light-chain fragment (VL)–enhanced yellow fluorescent protein (EYFP), was monitored by a bioluminescence resonance energy transfer (BRET) between the two. Upon simple mixing of

  10. A novel immunoassay based on the dissociation of immunocomplex and fluorescence quenching by gold nanoparticles

    Microsoft Academic Search

    Zhaofeng Peng; Zhaopeng Chen; Jianhui Jiang; Xiaobing Zhang; Guoli Shen; Ruqin Yu

    2007-01-01

    This study reports a novel, simple and sensitive immunoassay using fluorescence quenching caused by gold nanoparticles coated with antibody. The method is based on a non-competitive heterogeneous immunoassay of human IgG conducted by the typical procedure of sandwich immunocomplex formation. Goat anti-human IgG was first adsorbed on polystyrene microwells, and human IgG analyte was captured by the primary antibody and

  11. Development of a lateral flow immunoassay strip for screening of sulfamonomethoxine residues

    Microsoft Academic Search

    G. Zhang; X. Wang; A. Zhi; Y. Bao; Y. Yang; M. Qu; J. Luo; Q. Li; J. Guo; Z. Wang; J. Yang; G. Xing; S. Chai; T. Shi; Q. Liu

    2008-01-01

    A rapid lateral flow immunoassay screening method has been developed for the determination of sulfamonomethoxine (SMM) residues in swine urine. For this purpose, a specific monoclonal antibody (mAb), SMM4B9 for SMM, was generated and characterized. The mAb showed low cross-reactivity (not larger than 0.3%) to other sulfonamides and other potentially occurring analytes. Based on the competitive immunoassay principle, the strip

  12. Enzyme conversion immunoassay for determining total homocysteine in plasma or serum

    Microsoft Academic Search

    Frank Frantzen; Arne Ludvig Faaren; Ingrid Alfheim; Arne Kristian Nordhei

    A rapid and precise immunoassay for quantification of total homocysteine in blood samples is presented. The method avoids the use of radioisotopes and chromato- graphic separations and relies on enzymatic conversion of homocysteine to S-adenosyl-L-homocysteine, fol- lowed by quantification of S-adenosyl-L-homocysteine by an enzyme-linked immunoassay in microtiter format. The within- and between-assay imprecision is <6% and 8%, respectively, and results

  13. Basal level of prostaglandin D2 in rat brain by a solid-phase enzyme immunoassay.

    PubMed

    Hiroshima, O; Hayashi, H; Ito, S; Hayaishi, O

    1986-07-01

    A solid-phase enzyme immunoassay for prostaglandin D2 (PGD2) was developed in which PGD2 was labeled with horseradish peroxidase. After competitive binding to the immobilized antibody between enzyme-labeled and free PGD2, the activity of the enzyme bound to the antibody was assayed fluorometrically using 3-(p-hydroxyphenyl)-propionic acid and hydrogen peroxide as substrates. The procedure allowed determinations of 3-100 pg for PGD2. The IC50 value for PGD2 in the solid-phase enzyme immunoassay was about 25 pg and the sensitivity was improved about 10 times compared to those in radioimmunoassay and in solution-phase enzyme immunoassay. The solid-phase enzyme immunoassay was applied to the measurement of PGD2 content in rat brain and thereby an octadecylsilyl silica cartridge and a reversed-phase HPLC were sequentially used for sample preparations. Heads were immediately frozen in liquid nitrogen after decapitation to avoid a postmortem formation of PGD2. PGD2 contents measured by solid-phase enzyme immunoassay correlated well with the values obtained by radioimmunoassay (r = 0.966) after raising its contents by intravenous administration of PGD2. The in vivo level of PGD2 in rat brain was extremely low but determined to be 0.11 +/- 0.03 ng/g tissue (mean +/- S.E.M.) with this enzyme immunoassay. The result was equal to the value extrapolated to zero time from the postmortem change. PMID:3532208

  14. Magnetic-bead-based immunoassay using E. coli cells with autodisplayed Z-domains.

    PubMed

    Yoo, Gu; Bong, Ji-Hong; Park, Min; Kang, Min-Jung; Jose, Joachim; Pyun, Jae-Chul

    2013-07-10

    Escherichia coli cells with autodisplayed Z-domains could increase the sensitivity of immunoassays by immobilizing antibodies in a controlled orientation. In the work presented here, E. coli cells with autodisplayed Z-domains were immobilized to magnetic beads for subsequent immunoassay. In comparing conventional immunoassay using the E. coli cells with autodisplayed Z-domains, the magnetic-bead-based immunoassay improved immunoassay efficiency by minimizing the loss of E. coli cells during repeated centrifugation steps during washing. For the immobilization of E. coli cells to magnetic beads, the magnetic beads were modified with poly-l-lysine to bind to negatively charged E. coli cells. During the surface modification process, physical parameters such as the surface charge and size of the magnetic beads were analyzed to confirm the formation of E. coli-magnetic bead complexes. To test the feasibility of the magnetic-bead-based immunoassay, horseradish peroxidase (HRP) was used as a model analyte, and a biomarker for inflammatory diseases, C-reactive protein (CRP), was used for a demonstration of an application in medical diagnosis. PMID:23769312

  15. A straightforward immunoassay applicable to a wide range of antibodies based on surface enhanced fluorescence.

    PubMed

    Zhang, Ruohu; Wang, Zhuyuan; Song, Chunyuan; Yang, Jing; Cui, Yiping

    2013-05-01

    A straightforward immunoassay based on surface enhanced fluorescence (SEF) has been demonstrated using a fluorescent immune substrate and antibody functionalized-silver nanoparticles. Unlike the conventional SEF-based immunoassay, which usually uses the dye-labeled antibodies and the metallic nanostructured-substrates, the presented immune system does not need the antibodies to be labeled with dye molecules. Thus, this immunoassay can be easily applied to the detection of a wide range of target antigens, which is of great importance for its practical application. The experimental results show that this immunoassay has a good specificity as well as the capacity of quantitative detection. Basically, the surface density of the immuno-adsorbed silver nanoparticles increases with the increased amount of target antigens, resulting in a fluorescence enhancement up to around 7 fold. The dose-responsive performance of the immunoassay has been investigated and the limit of detection (LOD) is 1 ng/mL. Due to its simple preparation method and the wide range of detectable antigens, this presented immunoassay is expected to be helpful for extending the SEF-based application. PMID:23463294

  16. Effective gasoline site assessment using the D TECH{trademark} BTEX immunoassay

    SciTech Connect

    Hudak, R.T.; Melby, J.M.; Stave, J.W. [Strategic Diagnostics Inc., Newark, DE (United States)

    1994-12-31

    The application of immunoassay to environmental testing can greatly aid in assessing sites for various contaminants including PCB, TNT, RDX, PAH and BTEX. Immunoassay offers several benefits to site assessment: it is accurate, reproducible and relatively inexpensive compared to instrumental analysis. In addition, because of its ease-of-use, this technique is ideal for the field and requires minimal user training. To demonstrate not only the effectiveness of the BTEX immunoassay, but also the reliability of the field results, a gasoline contaminated site was assessed comparing the BTEX immunoassay to gas chromatography. All sampling and site related activities were executed in accordance to the USEPA SW-846 guidelines. Three (3) analyses were performed on each sample. One immunoassay analysis was performed in the field by an individual who received two (2) hours of training prior to the start of the study. A technician familiar with the immunoassay ran the second analysis in a laboratory. Finally, an independent GC laboratory certified for BTEX method 8020 and 602 performed the GC analyses. One hundred one (101) samples were analyzed: thirty-nine (39) samples were water, the other sixty-two (62) were soils ranging from clay to silt. The results and costs of the methods are compared.

  17. Evaluation of the Medically Complex Living Kidney Donor

    PubMed Central

    Caliskan, Yasar; Yildiz, Alaattin

    2012-01-01

    Due to organ shortage and difficulties for availability of cadaveric donors, living donor transplantation is an important choice for having allograft. Live donor surgery is elective and easier to organize prior to starting dialysis thereby permitting preemptive transplantation as compared to cadaveric transplantation. Because of superior results with living kidney transplantation, efforts including the usage of “Medically complex living donors” are made to increase the availability of organs for donation. The term “Complex living donor” is probably preferred for all suboptimal donors where decision-making is a problem due to lack of sound medical data or consensus guidelines. Donors with advanced age, obesity, asymptomatic microhematuria, proteinuria, hypertension, renal stone disease, history of malignancy and with chronic viral infections consist of this complex living donors. This medical complex living donors requires careful evaluation for future renal risk. In this review we would like to present the major issues in the evaluation process of medically complex living kidney donor. PMID:22655169

  18. Immunoassays Based on Penicillium marneffei Mp1p Derived from Pichia pastoris Expression System for Diagnosis of Penicilliosis

    PubMed Central

    Wang, Yan-Fang; Cai, Jian-Piao; Wang, Ya-Di; Dong, Hui; Hao, Wei; Jiang, Ling-Xiao; Long, Jun; Chan, Cheman; Woo, Patrick C. Y.; Lau, Susanna K. P.; Yuen, Kwok-Yung; Che, Xiao-Yan

    2011-01-01

    Background Penicillium marneffei is a dimorphic fungus endemic in Southeast Asia. It can cause fatal penicilliosis in humans, particularly in HIV-infected people. Diagnosis of this infection is difficult because its clinical manifestations are not distinctive. Specialized laboratory tests are necessary to establish a definitive diagnosis for successful management. We have demonstrated previously that a cell wall mannoprotein Mp1p, abundant in P. marneffei, is a potential biomarker for diagnosis of P. marneffei infections. In the present study, we describe immunoassays based on Mp1p derived from the yeast Pichia pastoris expression system. Methodology/Principal Findings We generated monoclonal antibodies (MAbs) and rabbit polyclonal antibodies (PAbs) against Mp1p expressed in P. pastoris. Subsequently, we developed two Mp1p antigen capture ELISAs which employed MAbs for both the capture and detecting antibodies (MAb-MAb pair) or PAbs and MAbs as the capture and detecting antibodies (PAbs-MAb pair) respectively. The two Mp1p antigen ELISAs detected Mp1p specifically in cultures of P. marneffei yeast phase at 37–40°C and had no cross-reaction with other tested pathogenic fungi. The sensitivities and specificities of the two antigen assays were found to be 55% (11/20) and 99.6% (538/540) for MAb-MAb Mp1p ELISA, and 75% (15/20) and 99.4% (537/540) for PAbs-MAb Mp1p ELISA performed using 20 sera with culture-confirmed penicilliosis, and 540 control sera from 15 other mycosis patients and 525 healthy donors. Meanwhile, we also developed an anti-Mp1p IgG antibody ELISA with an evaluated sensitivity of 30% (6/20) and a specificity of 98.5% (532/540) using the same sera. Furthermore, combining the results of Mp1p antigen and antibody detection improved the sensitivity of diagnosis to 100% (20/20). Conclusions/Significance Simultaneous detection of antigen and antibody using the immunoassays based on Mp1p derived from P. pastoris greatly improves detection sensitivity. The procedures should be useful for the routine diagnosis of penicilliosis. PMID:22205971

  19. Building Better Donors: A Well-Informed Donor is an Asset to Any Institution

    ERIC Educational Resources Information Center

    Minter, Michele

    2011-01-01

    Billionaire philanthropists compare notes in private with their peers. Whether experienced philanthropists or first-time donors, they all want their gifts to make a difference, and they are hungry for knowledge about how to be effective donors. They want to be educated about philanthropy. Educational institutions are experts at making the case for…

  20. Reimbursement for Living Kidney Donor Follow-Up Care: How Often Does Donor Insurance Pay?

    PubMed Central

    Kher, Ajay; Rodrigue, James; Ajaimy, Maria; Wasilewski, Marcy; Ladin, Keren; Mandelbrot, Didier

    2014-01-01

    Background Currently, many transplantation centers do not follow former living kidney donors on a long-term basis. Several potential barriers have been identified to provide this follow-up of former living kidney donors, including concerns that donor insurance will not reimburse transplantation centers or primary care physicians for this care. Here, we report the rates at which different insurance companies reimbursed our transplantation center for follow-up visits of living donors. Methods We collected data on all yearly follow-up visits of living donors billed from January 1, 2007, to December 31, 2010, representing 82 different donors. Concurrent visits of their recipients were available for 47 recipients and were used as a control group. Results We find that most bills for follow-up visits of living kidney donors were paid by insurance companies, at a rate similar to the reimbursement for recipient follow-up care. Conclusions Our findings suggest that, for former donors with insurance, inadequate reimbursement should not be a barrier in providing follow-up care. PMID:23060280

  1. Socioeconomic status and ethnicity of deceased donor kidney recipients compared to their donors.

    PubMed

    Adler, J T; Hyder, J A; Elias, N; Nguyen, L L; Markmann, J F; Delmonico, F L; Yeh, H

    2015-04-01

    Public perception and misperceptions of socioeconomic disparities affect the willingness to donate organs. To improve our understanding of the flow of deceased donor kidneys, we analyzed socioeconomic status (SES) and racial/ethnic gradients between donors and recipients. In a retrospective cohort study, traditional demographic and socioeconomic factors, as well as an SES index, were compared in 56,697 deceased kidney donor and recipient pairs transplanted between 2007 and 2012. Kidneys were more likely to be transplanted in recipients of the same racial/ethnic group as the donor (p?donor organ quality and SES (p?donor kidneys do not appear to be transplanted from donors of lower SES to recipients of higher SES; this information may be useful in counseling potential donors and their families regarding the distribution of their organ gifts. PMID:25758952

  2. The Effect of Donor Age on Corneal Transplantation Outcome: Results of the Cornea Donor Study

    PubMed Central

    2009-01-01

    Objective To determine whether graft survival over a 5-year follow-up period using corneal tissue from donors older than 65 years of age is similar to graft survival using corneas from younger donors. Design Multi-center prospective, double-masked, controlled clinical trial Participants 1090 subjects undergoing corneal transplantation for a moderate risk condition (principally Fuchs’ dystrophy or pseudophakic corneal edema); 11 subjects with ineligible diagnoses were not included Methods 43 participating eye banks provided corneas from donors in the age range of 12 to 75 with endothelial cell densities of 2300 to 3300 cells/mm2, using a random approach without respect to recipient factors. The 105 participating surgeons at 80 sites were masked to information about the donor cornea including donor age. Surgery and post-operative care were performed according to the surgeons’ usual routines. Subjects were followed for five years. Main Outcome Measures Graft failure, defined as a regraft or a cloudy cornea that was sufficiently opaque as to compromise vision for a minimum of three consecutive months. Results The 5-year cumulative probability of graft survival was 86% in both the <66.0 donor age group and the ?66.0 donor age group (difference = 0%, upper limit of one-sided 95% confidence interval = 4%). In a statistical model with donor age as a continuous variable, there was not a significant relationship between donor age and outcome (P=0.11). Three graft failures were due to primary donor failure, 8 to uncorrectable refractive error, 48 to graft rejection, 46 to endothelial decompensation (23 of which had a prior, resolved episode of probable or definite graft rejection), and 30 to other causes. The distribution of the causes of graft failure did not differ between donor age groups. Conclusions Five-year graft survival for cornea transplants at moderate risk for failure is similar using corneas from donors ? 66.0 years and donors < 66.0 years. Surgeons and patients now have evidence that corneas comparable in quality to those used in this study from donors through age 75 years are suitable for transplantation. PMID:18387407

  3. Prevalence of p24 antigen among a cohort of HIV antibody negative blood donors in Sokoto, North Western Nigeria - the question of safety of blood transfusion in Nigeria

    PubMed Central

    Osaro, Erhabor; Mohammed, Ndakotsu; Zama, Isaac; Yakubu, Abdulrahaman; Dorcas, Ikhuenbor; Festus, Aghedo; Kwaifa, Ibrahim; Sani, Ibrahim

    2014-01-01

    Introduction Blood transfusions remain a substantial source of HIV in SSA particularly among children and pregnant women. Aims and objectives: This aim of this retrospective study was to investigate the prevalence of p24 antigen among HIV antibody seronegative blood donors in Sokoto, North West Nigeria. Methods A total of 15,061 HIV antibody negative blood donors with mean age and age range (29.2 ± 8.18 and 18-50 years) were screened for p24 antigen between January 2010 to July 2013 using the Diapro Diagnostic immunoassay kit for P24 antigen (King Hawk Pharmaceuticals Beijing China). Results The overall prevalence of p24 antigen among the HIV antibody negative donors sample was 5.84%. The yearly prevalence was 9.79, 8.12, 2.7 and 2.84% respectively in 2010, 2011, 2012 and 2013. Of the total number of blood donor tested, 14,968 (99.38%) were males while 93 (0.62%) were females. The prevalence of P24 antigen was significantly higher among male blood donors 873 (5.8%) compared to females 7(0.05%), (p= 0.001). P24 positivity was significantly higher among blood group O blood donors compared to A, B and AB donors (494 (3.29%) compared to 184 (1.89%), 196 (1.30%) and 6 (0.04%)) respectively, p = 0.001). The prevalence of P24 antigen was significantly higher among Rhesus positive blood donors compared to Rhesus negative (807 (5.36%) versus 73 (0.48%), p =0.001). Conclusion Blood transfusion in Nigeria is associated with increased risk of HIV transmission. There is the urgent need to optimize the screening of blood donors in Nigeria by the inclusion of p24 antigen testing into the blood donor screening menu. The Nigerian government urgently need to adopt the WHO blood safety strategies to reduce the risk of transmission of HIV through blood transfusion. PMID:25419301

  4. Spin-Lattice Relaxation Times of Single Donors and Donor Clusters in Silicon

    NASA Astrophysics Data System (ADS)

    Hsueh, Yu-Ling; Büch, Holger; Tan, Yaohua; Wang, Yu; Hollenberg, Lloyd C. L.; Klimeck, Gerhard; Simmons, Michelle Y.; Rahman, Rajib

    2014-12-01

    An atomistic method of calculating the spin-lattice relaxation times (T1 ) is presented for donors in silicon nanostructures comprising of millions of atoms. The method takes into account the full band structure of silicon including the spin-orbit interaction. The electron-phonon Hamiltonian, and hence, the deformation potential, is directly evaluated from the strain-dependent tight-binding Hamiltonian. The technique is applied to single donors and donor clusters in silicon, and explains the variation of T1 with the number of donors and electrons, as well as donor locations. Without any adjustable parameters, the relaxation rates in a magnetic field for both systems are found to vary as B5 , in excellent quantitative agreement with experimental measurements. The results also show that by engineering electronic wave functions in nanostructures, T1 times can be varied by orders of magnitude.

  5. Spin-lattice relaxation times of single donors and donor clusters in silicon.

    PubMed

    Hsueh, Yu-Ling; Büch, Holger; Tan, Yaohua; Wang, Yu; Hollenberg, Lloyd C L; Klimeck, Gerhard; Simmons, Michelle Y; Rahman, Rajib

    2014-12-12

    An atomistic method of calculating the spin-lattice relaxation times (T?) is presented for donors in silicon nanostructures comprising of millions of atoms. The method takes into account the full band structure of silicon including the spin-orbit interaction. The electron-phonon Hamiltonian, and hence, the deformation potential, is directly evaluated from the strain-dependent tight-binding Hamiltonian. The technique is applied to single donors and donor clusters in silicon, and explains the variation of T? with the number of donors and electrons, as well as donor locations. Without any adjustable parameters, the relaxation rates in a magnetic field for both systems are found to vary as B?, in excellent quantitative agreement with experimental measurements. The results also show that by engineering electronic wave functions in nanostructures, T? times can be varied by orders of magnitude. PMID:25541787

  6. Disclosing recipient information to potential living donors: preferences of donors and recipients, before and after surgery.

    PubMed

    Rodrigue, J R; Ladin, K; Pavlakis, M; Mandelbrot, D A

    2011-06-01

    Consensus guidelines, while recommending that potential living donors should be given information that could impact their donation decision, are nonspecific about the types of information that should be disclosed. We surveyed potential (n = 36) and past (n = 45) living donors and transplant candidates (n = 45) and recipients (n = 45) about their preferences for sharing or knowing specific information about the recipient, how this information would impact decision-making, and who should be responsible for disclosing information. Potential donors were less likely than all others to feel that recipient information should be disclosed to potential donors. Donors and recipients felt most strongly about disclosing if the recipient lost a previously transplanted kidney due to medication nonadherence as well as the likelihood of 1- and 5-year graft survival. Most donors would be less likely to pursue donation if the recipient lost a previously transplanted kidney due to medication nonadherence or generally had problems with taking medications as prescribed. Transplant programs should consider how to best balance the potential donor's right to receive information that could reasonably be expected to affect their decision-making process with the recipient's right to privacy and confidentiality. PMID:21645257

  7. Alternative donors extend transplantation for patients with lymphoma who lack an HLA matched donor.

    PubMed

    Bachanova, V; Burns, L J; Wang, T; Carreras, J; Gale, R P; Wiernik, P H; Ballen, K K; Wirk, B; Munker, R; Rizzieri, D A; Chen, Y-B; Gibson, J; Akpek, G; Costa, L J; Kamble, R T; Aljurf, M D; Hsu, J W; Cairo, M S; Schouten, H C; Bacher, U; Savani, B N; Wingard, J R; Lazarus, H M; Laport, G G; Montoto, S; Maloney, D G; Smith, S M; Brunstein, C; Saber, W

    2015-02-01

    Alternative donor transplantation is increasingly used for high-risk lymphoma patients. We analyzed 1593 transplant recipients (2000-2010) and compared transplant outcomes in recipients of 8/8 allele HLA-A, -B, -C and DRB1 matched unrelated donors (MUDs; n=1176), 7/8 allele HLA mismatched unrelated donors (MMUDs; n=275) and umbilical cord blood donors (1 or 2 units UCB; n=142). Adjusted 3-year non-relapse mortality of MMUD (44%) was higher as compared with MUD (35%; P=0.004), but similar to UCB recipients (37%; P=0.19), although UCB had lower rates of neutrophil and platelet recovery compared with unrelated donor groups. With a median follow-up of 55 months, 3-year adjusted cumulative incidence of relapse was lower after MMUD compared with MUD (25% vs 33%, P=0.003) but similar between UCB and MUD (30% vs 33%; P=0.48). In multivariate analysis, UCB recipients had lower risks of acute and chronic GVHD compared with adult donor groups (UCB vs MUD: hazard ratio (HR)=0.68, P=0.05; HR=0.35; P<0.001). Adjusted 3-year OS was comparable (43% MUD, 37% MMUD and 41% UCB). These data highlight the observation that patients with lymphoma have acceptable survival after alternative donor transplantation. MMUD and UCB can extend the curative potential of allotransplant to patients who lack suitable HLA matched sibling or MUD. PMID:25402415

  8. Attaining specific donor management goals increases number of organs transplanted per donor: a quality improvement project.

    PubMed

    Hagan, Michael E; McClean, Daniel; Falcone, Cassandra A; Arrington, Jeffrey; Matthews, Donna; Summe, Carrie

    2009-09-01

    Most organ procurement organization professionals and transplant surgeons intuitively know that meeting donor management goals improves organ allocation and transplant outcomes. In this era of evidence-based medicine, it is important to know whether the data support this assumption. All 6 organ procurement organizations in the United Network for Organ Sharing's region 10 agreed on 6 specific donor management goals. The organ procurement organizations then compared the number of organs transplanted per donor when goals were met with the number when goals were not met. Results were broken down by donor type: standard-criteria donation, expanded-criteria donation, and donation after cardiac death. For all 6 organ procurement organizations combined, the data for all of 2008 show a substantial and statistically significant improvement in number of organs transplanted per donor for standard criteria donation and total donors when goals are met, with a smaller degree of improvement (although not statistically significant) in the number of organs transplanted per donor for expanded-criteria donation and donation after cardiac death when goals are met. PMID:19813484

  9. The development of a fluorescence polarization immunoassay for aflatoxin detection.

    PubMed

    Sheng, Ya Jie; Eremin, Sergei; Mi, Tie Jun; Zhang, Su Xia; Shen, Jian Zhong; Wang, Zhan Hui

    2014-02-01

    A fluorescence polarization immunoassay (FPIA) was developed for the analysis ofaflatoxins (AFs) using an anti-aflatoxin B1 (AFB1) monoclonal antibody and a novel fluorescein-labeled AFB1 tracer. The FPIA showed an IC50 value of 23.33 ng/mL with a limit of detection of 13.12 ng/mL for AFB1. The cross-reactivities of AFB1, AFB2, AFG1, AFG2, AFM1, and AFM2 with the antibody were 100%, 65.7%, 143%, 23.5%, 111.4%, and 2%, respectively. The group-specificity of anti-AFB1mAb indicated that the FPIA could potentially be used in a screening method for the detection of total AFs, albeit not AFG2 and AFM2. The total time required for analyzing 96 samples in one microplate was less than 5 min. This study demonstrates the potential usefulness of the FPIA as a rapid and simple technique for monitoring AFs. PMID:24625404

  10. System and method for a parallel immunoassay system

    DOEpatents

    Stevens, Fred J. (Naperville, IL)

    2002-01-01

    A method and system for detecting a target antigen using massively parallel immunoassay technology. In this system, high affinity antibodies of the antigen are covalently linked to small beads or particles. The beads are exposed to a solution containing DNA-oligomer-mimics of the antigen. The mimics which are reactive with the covalently attached antibody or antibodies will bind to the appropriate antibody molecule on the bead. The particles or beads are then washed to remove any unbound DNA-oligomer-mimics and are then immobilized or trapped. The bead-antibody complexes are then exposed to a test solution which may contain the targeted antigens. If the antigen is present it will replace the mimic since it has a greater affinity for the respective antibody. The particles are then removed from the solution leaving a residual solution. This residual solution is applied a DNA chip containing many samples of complimentary DNA. If the DNA tag from a mimic binds with its complimentary DNA, it indicates the presence of the target antigen. A flourescent tag can be used to more easily identify the bound DNA tag.

  11. Rapid dioxin screening of milk and water by enzyme immunoassay

    SciTech Connect

    Harrison, R.O. [ImmunoSystems Inc., Scarborough, ME (United States); Carlson, R.E. [Ecochem Research, Inc., Chaska, MN (United States); Shirkhan, H. [Fluid Management Systems, Inc., Atlanta, GA (United States)

    1995-12-01

    A simple and easy to use enzyme immunoassay (EIA) system has been developed for rapid screening of 2,3,7,8-tetrachlorodibenzo-p-dioxin (2378D). This EIA has been adapted to analysis of water and milk using an automated system for extraction of liquid samples. Water analysis can be performed directly following extraction and solvent exchange with no extract clean-up. The same automated system is used for milk extraction and the extract is then cleaned chromatographically using the automated FMS Dioxin-Prep{trademark} System. Sensitivity for 2378D in the EIA is approximately 100 pg per analysis. Thus sensitivity to 10 ppt 2378D (whole weight basis) in milk is possible using only 50 ml or less of sample and sensitivity to 0.1 ppt 2378D in water is possible using 1-2 liters of sample. Total time for sample preparation and analysis is about 3 hours for water and 4.5 hours for milk.

  12. A Portable Analyzer for Pouch-Actuated, Immunoassay Cassettes.

    PubMed

    Qiu, Xianbo; Liu, Changchun; Mauk, Michael G; Hart, Robert W; Chen, Dafeng; Qiu, Jing; Kientz, Terry; Fiene, Jonathan; Bau, Haim H

    2011-12-15

    A portable, small footprint, light, general purpose analyzer (processor) to control the flow in immunoassay cassettes and to facilitate the detection of test results is described. The durable analyzer accepts disposable cassettes that contain pouches and reaction chambers for various unit operations such as hydration of dry reagents, stirring, and incubation. The analyzer includes individually controlled, linear actuators to compress the pouches in the cassette, which facilitates the pumping and mixing of sample and reagents, and to close diaphragm-based valves for flow control. The same types of actuators are used to compress pouches and actuate valves. The analyzer also houses a compact OEM scanner/reader to excite fluorescence and detect emission from labels. The analyzer is hydraulically isolated from the cassette, reducing the possibility of cross-contamination. The analyzer facilitates programmable, automated execution of a sequence of operations such as pumping and valving in a timely fashion, reducing the level of expertise required from the operator and the possibility for errors. The analyzer's design is modular and expandable to accommodate cassettes of various complexities and additional functionalities. In this paper, the utility of the analyzer has been demonstrated with the execution of a simple, consecutive, lateral flow assay of a model biological system and the test results were detected with up converting phosphor labels that are excited at infrared frequencies and emit in the visible spectrum. PMID:22125359

  13. Backscattering particle immunoassays in wire-guide droplet manipulations.

    PubMed

    Yoon, Jeong-Yeol; You, David J

    2008-01-01

    A simpler way for manipulating droplets on a flat surface was demonstrated, eliminating the complications in the existing methods of open-surface digital microfluidics. Programmed and motorized movements of 10 muL droplets were demonstrated using stepper motors and microcontrollers, including merging, complicated movement along the programmed path, and rapid mixing. Latex immunoagglutination assays for mouse immunoglobulin G, bovine viral diarrhea virus and Escherichia coli were demonstrated by merging two droplets on a superhydrophobic surface (contact angle = 155 +/- 2 degrees ) and using subsequent back light scattering detection, with detection limits of 50 pg mL-1, 2.5 TCID50 mL-1 and 85 CFU mL-1, respectively, all significantly lower than the other immunoassay demonstrations in conventional microfluidics (~1 ng mL-1 for proteins, ~100 TCID50 mL-1 for viruses and ~100 CFU mL-1 for bacteria). Advantages of this system over conventional microfluidics or microwell plate assays include: (1) minimized biofouling and repeated use (>100 times) of a platform; (2) possibility of nanoliter droplet manipulation; (3) reprogrammability with a computer or a game pad interface. PMID:19014703

  14. The microassay on a card: A rugged, portable immunoassay

    NASA Technical Reports Server (NTRS)

    Kidwell, David

    1991-01-01

    The Microassay on a Card (MAC) is a portable, hand-held, non-instrumental immunoassay that can test for the presence of a wide variety of substances in the environment. The MAC is a simple device to use. A drop of test solution is placed on one side of the card and within five minutes a color is developed on the other side in proportion to the amount of substance in the test solution, with sensitivity approaching 10 ng/ml. The MAC is self-contained and self-timed; no reagents or timing is necessary. The MAC may be configured with multiple wells to provide simultaneous testing for multiple species. As envisioned, the MAC will be employed first as an on-site screen for drugs of abuse in urine or saliva. If the MAC can be used as a screen of saliva for drugs of abuse, it could be applied to driving while intoxicated, use of drugs on the job, or testing of the identity of seized materials. With appropriate modifications, the MAC also could be used to test for environmental toxins or pollutants.

  15. Aqueous two-phase systems enable multiplexing of homogeneous immunoassays

    PubMed Central

    Simon, Arlyne B.; Frampton, John P.; Huang, Nien-Tsu; Kurabayashi, Katsuo; Paczesny, Sophie; Takayama, Shuichi

    2014-01-01

    Quantitative measurement of protein biomarkers is critical for biomarker validation and early disease detection. Current multiplex immunoassays are time consuming costly and can suffer from low accuracy. For example, multiplex ELISAs require multiple, tedious, washing and blocking steps. Moreover, they suffer from nonspecific antibody cross-reactions, leading to high background and false-positive signals. Here, we show that co-localizing antibody-bead pairs in an aqueous two-phase system (ATPS) enables multiplexing of sensitive, no-wash, homogeneous assays, while preventing nonspecific antibody cross-reactions. Our cross-reaction-free, multiplex assay can simultaneously detect picomolar concentrations of four protein biomarkers ((C-X-C motif) ligand 10 (CXCL10), CXCL9, interleukin (IL)-8 and IL-6) in cell supernatants using a single assay well. The potential clinical utility of the assay is demonstrated by detecting diagnostic biomarkers (CXCL10 and CXCL9) in plasma from 88 patients at the onset of the clinical symptoms of chronic graft-versus-host disease (GVHD). PMID:25083509

  16. 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 ?m width and 100 ?m 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.

  17. Enzyme immunoassay of thyroxin with a centrifugal analyzer

    SciTech Connect

    Izquierdo, J.M.; Sotorrio, P.; Quiros, A.

    1982-01-01

    We have applied a homogeneous enzyme immunoassay for determination of thyroxinin serum to the ''Cobas Bio'' centrifugal analyzer. To unbind thyroxin from its protein complex, serum is treated for 20 min with a solution of NaOH containing ''Lipex,'' an agent for sequestering free fatty acids. The immunoenzymic reaction is then automatically performed by the analyzer at 37/sup 0/C. To 20 ..mu..L of sample mixture is added 125 ..mu..L of reagent (thyroxin antibodies and NAD/sup +/) and this mixture is incubated for 10 s. Then 25 ..mu..L of start reagent (enzyme-thyroxin conjugate and malate substrate) is added and the change in absorbance is monitored at 340 nm. The standard curve is linear up to at least 200 ..mu..g of thyroxin per liter. Within-assay precision (CV) varied from 1.1 to 2.9%, between-assay precision from 3.1 to 7.8%. Analytical recovery of thyroxin was complete. The deviation of control samples from target values ranged from -2.1% to 7.0%. Interference by hemoglobin or bilirubin is negligible. Results compare favorably with those by radioimmunoassay.

  18. Designing novel nano-immunoassays: antibody orientation versus sensitivity

    NASA Astrophysics Data System (ADS)

    Puertas, S.; Moros, M.; Fernández-Pacheco, R.; Ibarra, M. R.; Grazú, V.; de la Fuente, J. M.

    2010-12-01

    There is a growing interest in the use of magnetic nanoparticles (MNPs) for their application in quantitative and highly sensitive biosensors. Their use as labels of biological recognition events and their detection by means of some magnetic method constitute a very promising strategy for quantitative high-sensitive lateral-flow assays. In this paper, we report the importance of nanoparticle functionalization for the improvement of sensitivity for a lateral-flow immunoassay. More precisely, we have found that immobilization of IgG anti-hCG through its polysaccharide moieties on MNPs allows more successful recognition of the hCG hormone. Although we have used the detection of hCG as a model in this work, the strategy of binding antibodies to MNPs through its sugar chains reported here is applicable to other antibodies. It has huge potential as it will be very useful for the development of quantitative and high-sensitive lateral-flow assays for its use on human and veterinary, medicine, food and beverage manufacturing, pharmaceutical, medical biologics and personal care product production, environmental remediation, etc.

  19. Evaluation of a new chemiluminescence immunoassay for diagnosis of syphilis

    PubMed Central

    2010-01-01

    Objective To assess the sensitivity, specificity, and feasibility of a new chemiluminescence immunoassay (CLIA) in the diagnosis of syphilis. Methods At first, a retrospective study was conducted, using 135 documented cases of syphilis and 30 potentially interfering samples and 80 normal sera. A prospective study was also performed by testing 2, 071 unselected samples for routine screening for syphilis. CLIA was compared with a nontreponemal test (TRUST) and a treponemal test (TPPA). Results There was an agreement of 100% between CLIA and TPPA in the respective study. The percentage of agreement among the 245 sera tested was 100.0%. Compared with TPPA, the specificity of CLIA was 99.9% (1817/1819), the sensitivity of CLIA was 100.0% (244/244) in the prospective study. CLIA showed 99.5% agreement with TPPA by testing 2, 071 unselected samples. And CLIA seemed to be more sensitive than TPPA in detecting the samples of primary syphilis. Conclusions CLIA is easy to perform and the indicator results are objective and unequivocal. It may be suitable for large-scale screening as a treponemal test substituted for TPPA. PMID:20452886

  20. Graphene oxide-based SPR biosensor chip for immunoassay applications

    NASA Astrophysics Data System (ADS)

    Chiu, Nan-Fu; Huang, Teng-Yi; Lai, Hsin-Chih; Liu, Kou-Chen

    2014-08-01

    This work develops a highly sensitive immunoassay sensor for use in graphene oxide sheet (GOS)-based surface plasmon resonance (SPR) chips. This sensing film, which is formed by chemically modifying a GOS surface, has covalent bonds that strongly interact with the bovine serum albumin (BSA), explaining why it has a higher sensitivity. This GOS film-based SPR chip has a BSA concentration detection limit that is 100 times higher than that of the conventional Au-film-based sensor. The affinity constants ( K A) on the GOS film-based SPR chip and the conventional SPR chip for 100 ?g/ml BSA are 80.82 × 106 M-1 and 15.67 × 106 M-1, respectively. Therefore, the affinity constant of the GOS film-based SPR chip is 5.2 times higher than that of the conventional chip. With respect to the protein-protein interaction, the SPR sensor capability to detect angle changes at a low concentration anti-BSA of 75.75 nM on the GOS film-based SPR chip and the conventional SPR chip is 36.1867 and 26.1759 mdeg, respectively. At a high concentration, anti-BSA of 378.78 nM on the GOS film-based SPR chip and the conventional SPR chip reveals two times increases in the SPR angle shift. Above results demonstrate that the GOS film is promising for highly sensitive clinical diagnostic applications.

  1. Graphene oxide-based SPR biosensor chip for immunoassay applications

    PubMed Central

    2014-01-01

    This work develops a highly sensitive immunoassay sensor for use in graphene oxide sheet (GOS)-based surface plasmon resonance (SPR) chips. This sensing film, which is formed by chemically modifying a GOS surface, has covalent bonds that strongly interact with the bovine serum albumin (BSA), explaining why it has a higher sensitivity. This GOS film-based SPR chip has a BSA concentration detection limit that is 100 times higher than that of the conventional Au-film-based sensor. The affinity constants (KA) on the GOS film-based SPR chip and the conventional SPR chip for 100 ?g/ml BSA are 80.82?×?106 M-1 and 15.67?×?106 M-1, respectively. Therefore, the affinity constant of the GOS film-based SPR chip is 5.2 times higher than that of the conventional chip. With respect to the protein-protein interaction, the SPR sensor capability to detect angle changes at a low concentration anti-BSA of 75.75 nM on the GOS film-based SPR chip and the conventional SPR chip is 36.1867 and 26.1759 mdeg, respectively. At a high concentration, anti-BSA of 378.78 nM on the GOS film-based SPR chip and the conventional SPR chip reveals two times increases in the SPR angle shift. Above results demonstrate that the GOS film is promising for highly sensitive clinical diagnostic applications. PMID:25232298

  2. Specific Immunoassays for Placental Alkaline Phosphatase As a Tumor Marker

    PubMed Central

    Stinghen, Sérvio T.; Moura, Juliana F.; Zancanella, Patrícia; Rodrigues, Giovanna A.; Pianovski, Mara A.; Lalli, Enzo; Arnold, Dodie L.; Minozzo, João C.; Callefe, Luis G.; Ribeiro, Raul C.; Figueiredo, Bonald C.

    2006-01-01

    Human placental (hPLAP) and germ cell (PLAP-like) alkaline phosphatases are polymorphic and heat-stable enzymes. This study was designed to develop specific immunoassays for quantifying hPLAP and PLAP-like enzyme activity (EA) in sera of cancer patients, pregnant women, or smokers. Polyclonal sheep anti-hPLAP antibodies were purified by affinity chromatography with whole hPLAP protein (ICA-PLAP assay) or a synthetic peptide (aa 57–71) of hPLAP (ICA-PEP assay); the working range was 0.1–11 U/L and cutoff value was 0.2 U/L EA for nonsmokers. The intra- and interassay coefficients of variation were 3.7%–6.5% (ICA-PLAP assay) and 9.0%–9.9% (ICA-PEP assay). An insignificant cross-reactivity was noted for high levels of unheated intestinal alkaline phosphatase in ICA-PEP assay. A positive correlation between the regression of tumor size and EA was noted in a child with embryonal carcinoma. It can be concluded that ICA-PEP assay is more specific than ICA-PLAP, which is still useful to detect other PLAP/PLAP-like phenotypes. PMID:17489017

  3. Sensitive Giant Magnetoresistive-based Immunoassay for Multiplex Mycotoxin Detection

    PubMed Central

    Mak, Andy C.; Osterfeld, Sebastian J.; Yu, Heng; Wang, Shan X.; Davis, Ronald W.; Jejelowo, Olufisayo A.; Pourmand, Nader

    2010-01-01

    Rapid and multiplexed measurement is vital in the detection of food-borne pathogens. While highly specific and sensitive, traditional immunochemical assays such as enzyme-linked immunosorbent assays (ELISAs) often require expensive read-out equipment (e.g. fluorescent labels) and lack the capability of multiplex detection. By combining the superior specificity of immunoassays with the sensitivity and simplicity of magnetic detection, we have developed a novel multiplex magnetic nanotag-based detection platform for mycotoxins that functions on a sub-picomolar concentration level. Unlike fluorescent labels, magnetic nanotags (MNTs) can be detected with inexpensive giant magnetoresistive (GMR) sensors such as spin-valve sensors. In the system presented here, each spin-valve sensor has an active area of 90 × 90 µm2, arranged in an 8×8 array. Sample is added to the antibody-immobilized sensor array prior to the addition of the biotinylated detection antibody. The sensor response is recorded in real time upon the addition of streptavidin-linked MNTs on the chip. Here we demonstrate the simultaneous detection of multiple mycotoxins (aflatoxins B1, zearalenone and HT-2) and show that a detection limit of 50 pg/mL can be achieved. PMID:20047828

  4. Quantitative immunochromatographic analysis: theory and application to theophylline immunoassay.

    PubMed

    Lee, S R; Liberti, P A

    1987-10-01

    The development of an immunochromatographic technique suitable for rapid analysis of biological fluids is described. Quasi-one-dimensional antibody lattices specific for theophylline were constructed by packing Sepharose beads conjugated with specific antibody into specially designed narrow capillary tubes. The design of these capillary columns was such that they would subtract a preset threshold quantity of antigen (label and analyte) from the total amount presented. Labeled antigen, which appeared in the flowthrough, could then be used to precisely quantitate the analyte present. The ideal format would permit very precise subtraction of 100% of the available antigen up to the threshold amount and none of the remainder. The microcolumn described here comes close to this ideal behavior through the attainment of very high ratios of bound/free antigen. The elevated bound/free ratio could be explained by theoretical analysis of the effect on equilibria of the high antibody concentration in this quasi-one-dimensional system. Lattices containing anti-theophylline antibodies were used to develop a competitive enzyme immunoassay for theophylline which demonstrated a dose-response that was closely similar to that predicted by theoretical treatment. The entire assay procedure was performed in less than 30 min and demonstrated a sensitivity limit of approximately 20 ng/ml. Preliminary studies on clinical serum samples suggest that this assay has potential for the routine analysis of biological fluids. PMID:3674415

  5. Amplified flow-cytometric separation-free fluorescence immunoassays

    SciTech Connect

    Saunders, G.C.; Jett, J.H.; Martin, J.C.

    1985-12-01

    An equilibrium-type competitive-binding fluorescence immunoassay with high sensitivity and excellent precision is described that obviates separation of free from bound label. In the assay relatively large (10 microns diameter) antibody-coated non-fluorescent particles and very small (0.10 micron diameter) antigen-coated fluorescent latex particles are used. Soluble nonlabeled antigen competes with antigen on the microspheres for antibody binding sites on the larger spheres. After equilibrium is attained, the fluorescence distribution of 5000 of the large spheres is measured in a flow cytometer. The mean values for the fluorescence distribution obtained from samples containing known concentrations of soluble antigen are used to construct a standard displacement curve. In a prototype assay for the antigen horseradish peroxidase, a sensitivity of 10(-12) mol/L has been achieved. Undiluted serum can be assayed without loss of sensitivity. Preliminary experiments also indicate that double-antibody sandwich-type assays of very high sensitivity (10(-14) mol/L) are also possible when this dual-sphere concept is exploited.

  6. Evaluation of the recombinant VlsE-based liaison chemiluminescence immunoassay for detection of Borrelia burgdorferi and diagnosis of Lyme disease.

    PubMed

    Ledue, Thomas B; Collins, Marilyn F; Young, John; Schriefer, Martin E

    2008-12-01

    Recent efforts to improve the serologic diagnosis of Lyme disease have included the use of a synthetic peptide (C6) that reproduces the sequence of invariable region 6 of VlsE, the variable surface antigen of Borrelia burgdorferi. In the present study, the diagnostic performance of DiaSorin's recombinant VlsE-based chemiluminescence immunoassay in 1,947 human serum samples was evaluated. Sensitivity was determined using two serum panels from the CDC. For panel I, we observed sensitivities of 68.4% and 75.6% for subjects with early, localized (n=19) or disseminated (n=41) disease, respectively. For panel II, we observed sensitivities of 61.5% and 100% for subjects with early (n=26) or late-stage (n=11) disease, respectively. We observed a specificity of 99.5% for healthy donors (n=600) living either in regions of the United States where the disease is endemic or in regions where it is not endemic. Overall, specificity among 207 potentially cross-reactive sera from subjects who had other spirochetal infections, nonspirochetal infections including bacterial and viral infections, or autoimmune or neurologic disease; who were positive for rheumatoid factor or anti-mouse antibodies; or who had been previously vaccinated for Lyme disease was 93.7%. In a direct comparison of 1,038 prospectively collected samples for Lyme disease testing we observed a relative sensitivity of 70%, a relative specificity of 99.1%, and an overall agreement of 97.1% between the DiaSorin recombinant VlsE chemiluminescence immunoassay and the Immunetics peptide-based C6 enzyme-linked immunosorbent assay. PMID:18945880

  7. Cross-reactivity of steroid hormone immunoassays: clinical significance and two-dimensional molecular similarity prediction

    PubMed Central

    2014-01-01

    Background Immunoassays are widely used in clinical laboratories for measurement of plasma/serum concentrations of steroid hormones such as cortisol and testosterone. Immunoassays can be performed on a variety of standard clinical chemistry analyzers, thus allowing even small clinical laboratories to do analysis on-site. One limitation of steroid hormone immunoassays is interference caused by compounds with structural similarity to the target steroid of the assay. Interfering molecules include structurally related endogenous compounds and their metabolites as well as drugs such as anabolic steroids and synthetic glucocorticoids. Methods Cross-reactivity of a structurally diverse set of compounds were determined for the Roche Diagnostics Elecsys assays for cortisol, dehydroepiandrosterone (DHEA) sulfate, estradiol, progesterone, and testosterone. These data were compared and contrasted to package insert data and published cross-reactivity studies for other marketed steroid hormone immunoassays. Cross-reactivity was computationally predicted using the technique of two-dimensional molecular similarity. Results The Roche Elecsys Cortisol and Testosterone II assays showed a wider range of cross-reactivity than the DHEA sulfate, Estradiol II, and Progesterone II assays. 6-Methylprednisolone and prednisolone showed high cross-reactivity for the cortisol assay, with high likelihood of clinically significant effect for patients administered these drugs. In addition, 21-deoxycortisol likely produces clinically relevant cross-reactivity for cortisol in patients with 21-hydroxylase deficiency, while 11-deoxycortisol may produce clinically relevant cross-reactivity in 11?-hydroxylase deficiency or following metyrapone challenge. Several anabolic steroids may produce clinically significant false positives on the testosterone assay, although interpretation is limited by sparse pharmacokinetic data for some of these drugs. Norethindrone therapy may impact immunoassay measurement of testosterone in women. Using two-dimensional similarity calculations, all compounds with high cross-reactivity also showed a high degree of similarity to the target molecule of the immunoassay. Conclusions Compounds producing cross-reactivity in steroid hormone immunoassays generally have a high degree of structural similarity to the target hormone. Clinically significant interactions can occur with structurally similar drugs (e.g., prednisolone and cortisol immunoassays; methyltestosterone and testosterone immunoassays) or with endogenous compounds such as 21-deoxycortisol that can accumulate to very high concentrations in certain disease conditions. Simple similarity calculations can help triage compounds for future testing of assay cross-reactivity. PMID:25071417

  8. Italian national survey of blood donors: external quality assessment (EQA) of syphilis testing.

    PubMed

    Vulcano, Francesca; Milazzo, Luisa; Volpi, Sabrina; Battista, Mara Maria; Barca, Alessandra; Hassan, Hamisa Jane; Pimpinelli, Fulvia; Giampaolo, Adele

    2010-03-01

    The detection of syphilis among blood donors may reveal high-risk sexual behavior, which can go unreported at the time of donor selection and compromise the safety of the donated blood. In Italy, blood is collected, tested, and distributed by transfusion services (TSs), which also perform outpatient transfusions. Although the TSs must screen for syphilis by law, there are no indications of the specific type of method to be used, generating discrepancies in the results obtained by the different TSs. To determine the proficiency of the TSs in screening for syphilis, we performed an external quality assessment (EQA). The EQA was based on two shipments of serum panels; 133 and 118 of the 326 existing TSs participated in the first and second shipments, respectively. Each panel consisted of both positive and negative serum samples. The results confirmed that the use of a single nontreponemal test (the Venereal Disease Research Laboratory [VDRL] and the rapid plasma reagin [RPR] tests) is the least sensitive means of identifying samples that are positive for syphilis antibodies. We also found that the interpretation of the results of manual techniques, such as the RPR test, the VDRL test, the Treponema pallidum hemagglutination (TPHA) assay, and the T. pallidum particle agglutination (TPPA) assay, can vary greatly among different TSs and operators. Total Ig enzyme immunoassays (EIAs) are the most sensitive. However, the determination of syphilis on the basis of the results of a single test is not sufficient for an accurate screening; and all blood units should thus be assessed by two distinct treponemal tests, that is, a total Ig EIA and the TPHA or the TPPA assay. PMID:20042617

  9. Theoretical and practical implications of a new definition of the minimal detectable concentration for immunoassays

    NASA Astrophysics Data System (ADS)

    Brown, Emery N.

    1996-04-01

    The minimal detectable concentration (MDC), the smallest analyte concentration an immunoassay can reliably measure, is a fundamental property of an assay. Different interpretations of 'the smallest concentration an immunoassay can reliably measure' have led to different mathematical formulations of the MDC definition. We interpret this concept to mean the smallest analyte concentration the immunoassay may report as greater than the zero dose with high probability, say 0.95. Using Bayes' theorem we have developed a new MDC definition and shown that each of the current definitions approximates some component of the new one. We extend our paradigm for computing the MDC and derive a statistical framework for analyzing uncertainty in small analyte concentrations. We compute for any immunoassay measurement the probability that it exceeds the zero dose, its 95% confidence interval, its coefficient-of-variation (CV) and the probability that it is greater than any previous measurement. We illustrate the framework in a study of theoretical data based on our previous analyses of the Abbott microparticle capture enzyme immunoassay assay (MEIA) for prostate- specific antigen (PSA). The paradigm provides a sounder conceptual and computational approach for measuring reliably low concentrations of biological substances and for defining a positive result for screening and diagnostic tests.

  10. Microfluidic immunoassay with plug-in liquid crystal for optical detection of antibody.

    PubMed

    Zhu, Qingdi; Yang, Kun-Lin

    2015-01-01

    Recent advance in liquid crystal (LqC) based immunoassays enables label-free detection of antibody, but manual preparation of LqC cells and injection of LqC are required. In this work, we developed a new format of LqC-based immunoassay which is hosted in a microfluidic device. In this format, the orientations of LqC are strongly influenced by four channel walls surrounding the LqC. When the aspect ratio (depth/width) of the channel is smaller than 0.38, LqC orients homeotropically inside the microchannel and appears dark. After antigens bind to immobilized antibodies on the channel walls, a shift of the LqC appearance from dark to bright (due to the disruption of LqC orientation) can be visualized directly. To streamline the immunoassay process, a tubing cartridge loaded with a sample solution, washing buffers and a plug of LqC is connected to the microfluidic device. By using pressure-driven flow, the cartridge allows antigen/antibody binding, washing and optical detection to be accomplished in a sequential order. We demonstrate that this microfluidic immunoassay is able to detect anti-rabbit IgG with a naked-eye detection limit down to 1 ?g mL(-1). This new format of immunoassay provides a simple and robust approach to perform LqC-based label-free immunodetection in microfluidic devices. PMID:25467520

  11. Preprogrammed, Parallel On-Chip Immunoassay Using System-Level Capillarity Control

    PubMed Central

    Kim, Sung-Jin; Paczesny, Sophie; Takayama, Shuichi; Kurabayashi, Katsuo

    2014-01-01

    Fully manual use of conventional multiwell plates makes enzyme-linked immunosorbent assay (ELISA)-based immunoassays highly time-consuming and labor-intensive. Here, we present a capillarity-driven on-chip immunoassay that greatly saves time and labor with an inexpensive setup. Our immunoassay process starts with pipetting multiple solutions into multiwells constructed on a microfluidic device chip. Subsequently, capillarity spontaneously transports multiple sample solutions and common reagent solutions into assigned detection channels on the chip in a purely passive and preprogrammed manner. Our device implements capillarity-driven immunoassays involving four sample and six reagent solutions within 30 min by orchestrating the functions of on-chip passive components. Notably, our immunoassay technique reduces the total number of pipetting processes by ~5 times, as compared to assays on multiwell plates (48 vs 10). This assay technique allows us to quantify the concentrations of C-reactive protein and suppressor of tumorigenicity 2 with a detection limit of 8 and 90 pM, respectively. This device should be useful for sophisticated, parallel biochemical microfluidic processing in point-of-care settings under limited resources. PMID:23789820

  12. Label-free impedimetric immunoassay for trace levels of polychlorinated biphenyls in insulating oil.

    PubMed

    Date, Yasumoto; Aota, Arata; Sasaki, Kazuhiro; Namiki, Yukie; Matsumoto, Norio; Watanabe, Yoshitomo; Ohmura, Naoya; Matsue, Tomokazu

    2014-03-18

    A rapid, ultrasensitive, and practical label-free impedimetric immunoassay for measuring trace levels of total polychlorinated biphenyls (PCBs) in insulating oil was developed. First, we developed a novel monoclonal antibody (RU6F9) for PCBs by using a designed immunogen and characterized its binding affinity for a commercial mixtures of PCBs and its main congeners. A micro comblike gold electrode was fabricated, and the antibody was covalently immobilized on the electrode through a self-assembled monolayer formed by dithiobis-N-succinimidyl propionate. The antigen-binding event on the surface of the functionalized electrode was determined as the change in charge transfer resistance by using electrochemical impedance spectroscopy. The resulting impedimetric immunoassay in aqueous solution achieved a wide determination range (0.01-10 ?g/L) and a low detection limit (LOD) of 0.001 ?g/L, which was 100-fold more sensitive than a conventional flow-based immunoassay for PCBs. By combining the impedimetric immunoassay with a cleanup procedure for insulating oil utilizing a multilayer cleanup column followed by DMSO partitioning, an LOD of 0.052 mg/kg-oil was achieved, which satisfied the Japanese regulation criterion of 0.5 mg/kg-oil. Finally, the immunoassay was employed to determine total PCB levels in actual used insulating oils (n = 33) sampled from a used transformer containing trace levels of PCBs, and the results agreed well with the Japanese official method (HRGC/HRMS). PMID:24528234

  13. Superfund Innovative Technology Evaluation Program demonstration plan for Westinghouse Bio-Analytic Systems pentachlorophenol immunoassays

    SciTech Connect

    Silverstein, M.E.; White, R.J.; Gerlach, R.W.; Van Emon, J.M.

    1992-04-14

    The plan provides a detailed design and description of the demonstration and evaluation program for the Westinghouse Bio-Analytic Systems immunoassay technologies specific for the analysis of pentachlorophenol. The immunoassays measure parts per billion concentrations of pentachlorophenol in water. The demonstration is being conducted under the Superfund Innovative Technology Evaluation (SITE) Program. It is expected that proper execution of the demonstration plan will provide information that enables data users and reviewers to assess the performance of the technology in terms of its usefulness and limitations for the Superfund Program. The main focus of the demonstration is to evaluate on site a semiquantitative immunoassay field analysis kit for its utility as a rapid field screening tool. The results obtained from the field kit analyses will be compared to those obtained from a quantitative high-sample-capacity plate immunoassay also developed by Westinghouse Bio-Analytic Systems. In addition, both immunoassay techniques will be compared to the standard gas chromatography/mass spectrometry procedure for pentachlorophenol determination. The quality assurance plan for the demonstration is provided in an appendix.

  14. Reaction paths in donor solvent coal liquefaction

    Microsoft Academic Search

    Arthur M. Squires

    1978-01-01

    The classic studies of Sol Weller and his collaborators1,2 provided the working model for most American investigations of donor solvent coal liquefaction. The investigations, particularly at what is now the Pittsburgh Energy Research Centre of ERDA, at what is now Conoco Coal Development Company, at Pittsburg and Midway Coal Company and at the University of Utah, added notably to Weller's

  15. Coal processing: the Exxon donor solvent process

    Microsoft Academic Search

    L. E. Furlong; E. Effron; L. W. Vernon; E. L. Wilson

    1976-01-01

    The development of the Exxon coal liquefaction process over 10 years is described. Exxon is using lower temperatures and lower pressures (approximately 100 bar) than were used in the Bergius process. The donor solvent is produced in a separate, fixed bed, catalytic hydrogenation step. Early research was broad in scope including, both hydrogenated and unhydrogenated recycle solvent studies. Alternate solids\\/liquids

  16. Organ Donor Recognition: Practical and Ethical Considerations

    Microsoft Academic Search

    Groot de Y. J

    2012-01-01

    The brain dead patient is the ideal multiorgan donor. Conditions that can lead to the state of brain death are limited. A subarachnoid haemorrhage, intracerebral haemorrhage or traumatic brain injury precede in 83% of the cases the state of brain death. Because of better prevention and treatment options of these conditions, we anticipate a further decline of brain death. Consequently,

  17. $500-$999.99 Anonymous Donor *

    E-print Network

    Dasgupta, Dipankar

    . Barbara S. Cook * Mr. James A. Cook Jr. Mr. Chris A. Cornaghie * Mr. Larry D. Cox * Ms. Joanna E. Curtis$500-$999.99 Anonymous Donor * Dr. Bette J. Ackerman Mr. Larry L. Adams * Prof. Lee Harris and Prof Atkins Ms. Katherine V. Atkinson * Mr. and Mrs. Howard D. Averyhart Sr. * Mr. Robert E. Bailey * Mr. Paul

  18. Carbocycles from donor-acceptor cyclopropanes.

    PubMed

    Grover, Huck K; Emmett, Michael R; Kerr, Michael A

    2015-01-21

    This review summarizes research directed towards the formation of carbocyclic adducts from donor-acceptor cyclopropanes. The focus of the review is on annulation and cycloaddition reactions (both inter- and intramolecularly) mediated by Lewis or protic acid, bases, or thermal conditions. Rearrangements resulting in carbocycles and those reactions mediated by transition metal catalysis have been excluded. PMID:25425071

  19. DONOR SPOTLIGHT BUSINESS LINKAGE STROKE TREATMENT

    E-print Network

    Goodhill, Geoffrey J.

    DONOR SPOTLIGHT BUSINESS LINKAGE STROKE TREATMENT BRAIN CANCER FUNDRAISER German Australian for more information and to book your table, please contact events@qbi.uq.edu.au now. What is stroke? Stroke occurs when the supply of blood to the brain is disrupted. A stroke caused by a blocked artery

  20. 21 CFR 610.41 - Donor deferral.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...610.47 when a donor tests reactive by a screening test for HIV or HCV required under § 610.40(a) and (b), or when you...other reliable test results or information indicating evidence of HIV or HCV infection. [66 FR 31164, June 11, 2001, as...

  1. 21 CFR 610.41 - Donor deferral.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...610.47 when a donor tests reactive by a screening test for HIV or HCV required under § 610.40(a) and (b), or when you...other reliable test results or information indicating evidence of HIV or HCV infection. [66 FR 31164, June 11, 2001, as...

  2. 21 CFR 610.41 - Donor deferral.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...610.47 when a donor tests reactive by a screening test for HIV or HCV required under § 610.40(a) and (b), or when you...other reliable test results or information indicating evidence of HIV or HCV infection. [66 FR 31164, June 11, 2001, as...

  3. Recruitment of Live Donors by Candidates for Kidney Transplantation

    PubMed Central

    Reese, Peter P.; Shea, Judy A.; Berns, Jeffrey S.; Simon, Maureen K.; Joffe, Marshall M.; Bloom, Roy D.; Feldman, Harold I.

    2008-01-01

    Background: Little is known about efforts that renal transplant candidates make to recruit live donors. It was hypothesized that preference for live donor kidney transplantation and greater knowledge about live donor transplantation are associated with candidates’ initiating conversations about donation with potential donors. Design, setting, participants, & measurements: A cross-sectional study of renal transplant candidates was performed at initial transplant evaluation. Candidates completed a questionnaire that specified whether they had initiated conversations about donation with any potential donors. The questionnaire also measured preference for live donor transplantation, knowledge about transplantation, concern about donor harm, willingness to ask for help in coping with kidney disease, and social support. Results: Ninety-six candidates participated. Forty-nine (51%) reported initiating a conversation with at least one potential donor. In multivariable logistic regression, domains associated with initiating a conversation included: preference for live donor transplantation, willingness to ask for help, and female gender. Older age was associated with a lower odds of initiating a conversation. Knowledge, concern about donor harm, social support, and ethnicity were not associated with initiating a conversation with a donor. Conclusions: Attempts at donor recruitment by kidney transplant candidates are common. These findings suggest that interventions that influence preferences about transplantation and willingness to ask others for help are logical targets to enhance access to live donor transplantation. PMID:18385392

  4. Label-free homogeneous FRET immunoassay for the detection of mycotoxins that utilizes quenching of the intrinsic fluorescence of antibodies.

    PubMed

    Li, Taihua; Byun, Ju-Young; Kim, Bo Bae; Shin, Yong-Beom; Kim, Min-Gon

    2013-04-15

    The phenomenon of fluorescence quenching of an antibody by a specific ligand was applied in developing a technique for detection of mycotoxins, such as aflatoxin B? (AFB?), ochratoxin A, and zearalenone. Studies showed that the intrinsic fluorescence of tryptophan (Trp) residues in antibodies, promoted by excitation at 280 nm, is quenched upon binding of specific mycotoxin ligands. Fluorescence quenching in FRET system takes place in these systems as a consequence of the overlap of the emission spectra of antibody donors with the absorption spectra of the mycotoxins. Further studies focusing on the detection of AFB? revealed that the Fab fragment, the variable region of the antibody where specific binding of AFB? occurs, can be utilized to increase the sensitivity of the detection system. The results demonstrate that fluorescence of the Fab fragment is almost completely quenched by AFB? whereas emission from intact anti-AFB? is only partially quenched by this mycotoxin. The limits of detection (LODs) were found to be 0.85 and 0.09 ng mL?¹ for assays using the intact antibody and the Fab fragment, respectively, corresponding to a 10-fold enhancement. A practical application of the Fab fragment based assay system was demonstrated by its use in the detection of AFB? in spiked barley grain samples. The observations made in this effort show that the new, label-free, non-competitive, and homogeneous FRET immunoassay strategy, which requires a simple sample preparation procedure, serves as a powerful tool for the rapid and sensitive quantitative determination of organic substances such as mycotoxin. PMID:23220067

  5. 75 FR 58400 - Donor Management Research: Improvements in Clinical Management of Deceased Organ Donors

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-24

    ...improve organ quality, organs transplanted per donor...Director, Division of Transplantation, Healthcare Systems...Director at Division of Transplantation, Healthcare Systems...SUPPLEMENTARY INFORMATION: Background Since 2002, HRSA has...Interventions to Increase Organ Procurement...

  6. Rapid detection of group B streptococcal antigen from vaginal specimens using a new Optical ImmunoAssay technique

    Microsoft Academic Search

    Choong H. Park; Davinder Ruprai; Nancy M. Vandel; Deborah L. Hixon; Fred E. Mecklenburg

    1996-01-01

    A total of 531 vaginal specimens were used to evaluate a new Optical ImmunoAssay (OIA) screening technique for the rapid detection of group B streptococcal antigen. The results of the OIA test, the ICON Strep B membrane immunoassay (Hybritech ICON), and conventional culture on sheep blood agar (direct TSA) were compared to broth enhanced culture. Results obtained from the OIA

  7. Saladax Biomedical 5FU PCM™ Immunoassay for Chemotherapy Treatment Individualization Promises Multiple Benefits in Treatment of Colorectal Cancer

    Microsoft Academic Search

    Dennis Dionne

    Bethlehem, PA., August 5, 2008 - A novel immunoassay blood test will make it easier for oncologists to accurately measure and personalize 5-fluorouracil (5-FU) dosing for patients undergoing continuous infusion chemotherapy regimens. Data from a multicenter study showed that a nanoparticle-based immunoassay from Saladax Biomedical, called 5-FU Personalized Chemotherapy Management (PCM), was validated against and performed as well as physical

  8. 21 CFR 640.21 - Suitability of donors.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Platelets § 640.21 Suitability of donors. (a) Whole blood donors shall meet the criteria for suitability prescribed...

  9. 21 CFR 640.21 - Suitability of donors.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Platelets § 640.21 Suitability of donors. (a) Whole blood donors shall meet the criteria for suitability prescribed...

  10. 21 CFR 640.21 - Suitability of donors.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Platelets § 640.21 Suitability of donors. (a) Whole blood donors shall meet the criteria for suitability prescribed...

  11. 21 CFR 640.21 - Suitability of donors.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Platelets § 640.21 Suitability of donors. (a) Whole blood donors shall meet the criteria for suitability prescribed...

  12. 21 CFR 640.73 - Reporting of fatal donor reactions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.73 Reporting of fatal donor reactions. If a donor has a fatal reaction which, in any way, may be...

  13. 21 CFR 640.66 - Immunization of donors.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.66 Immunization of donors. If specific immunization of a donor is to be performed, the selection...

  14. 21 CFR 640.66 - Immunization of donors.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.66 Immunization of donors. If specific immunization of a donor is to be performed, the selection...

  15. 21 CFR 640.73 - Reporting of fatal donor reactions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.73 Reporting of fatal donor reactions. If a donor has a fatal reaction which, in any way, may be...

  16. 21 CFR 640.66 - Immunization of donors.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.66 Immunization of donors. If specific immunization of a donor is to be performed, the selection...

  17. 21 CFR 640.73 - Reporting of fatal donor reactions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.73 Reporting of fatal donor reactions. If a donor has a fatal reaction which, in any way, may be...

  18. 21 CFR 640.73 - Reporting of fatal donor reactions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.73 Reporting of fatal donor reactions. If a donor has a fatal reaction which, in any way, may be...

  19. 21 CFR 640.66 - Immunization of donors.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.66 Immunization of donors. If specific immunization of a donor is to be performed, the selection...

  20. 21 CFR 640.66 - Immunization of donors.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.66 Immunization of donors. If specific immunization of a donor is to be performed, the selection...

  1. 21 CFR 640.73 - Reporting of fatal donor reactions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.73 Reporting of fatal donor reactions. If a donor has a fatal reaction which, in any way, may be...

  2. 21 CFR 640.21 - Suitability of donors.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 false Suitability of donors. 640.21 Section 640.21 Food and Drugs FOOD AND DRUG ADMINISTRATION...STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Platelets § 640.21 Suitability of donors. (a) Whole blood...

  3. Immunoassay based water quality analysis: A new tool for drinking water supply management

    SciTech Connect

    Kostyshyn, C.R. [Ohmicron Environmental Diagnostics, Inc., Newton, PA (United States); Brown, W.; Hervey, E. [City Water Light and Power, Springfield, IL (United States); Hull, C. [Water & Pollution Control Department, Kanasa City, MO (United States)] [and others

    1996-11-01

    The recent availability of enzyme-linked immunosorbent assay (ELISA) tests for the analysis of organic environmental contaminants provides drinking water utility managers and operators with a new tool for managing treatment operations and monitoring source watersheds. Immunoassay technology permits rapid, inexpensive and accurate in-plant testing of many SDWA regulated organic contaminants at concentrations well below established MCL`s. Analytical testing which would not be practicable due to the high cost or long turnaround time limitations of conventional testing methods is now being performed using immunoassay based analysis. Water quality data generated using immunoassay based methods are being utilized by drinking water utilities as an integral part of source watershed management programs, process operations optimization efforts, pro-active raw and finished water testing programs, and flood and incident response management.

  4. BTEX site assessment by D TECH{trademark} immunoassay: A rapid and cost-effective technique

    SciTech Connect

    Hudak, R.T.; Melby, J.M.; Stave, J.W. [Strategic Diagnostics Inc., Newark, DE (United States)

    1994-12-31

    Recent advances in immunoassay, a technique widely accepted as the method of choice for in-vitro diagnostics, have greatly contributed to the detection of environmental contamination. The development of assays for various contaminants, including BTEX, has allowed for an easy and rapid site characterization allows for a more accurate site assessment, largely due to the elimination of the volatility and biodegradation concerns related to BTEX analyses. To demonstrate the performance of the enzyme immunoassay, several field studies were conducted with concurrent analyses by both immunoassay and gas chromatography (GC). In these studies, samples were split into two aliquots in the field. One aliquot was analyzed on-site using the D TECH BTEX kit, the other was sent to a certified laboratory for SW-846 method 8020 GC analysis. The results and subsequent costs of each analysis technique are compared.

  5. Characterization of Magnetic Markers for Liquid-Phase Immunoassays Using Brownian Relaxation

    NASA Astrophysics Data System (ADS)

    Enpuku, Keiji; Watanabe, Hideki; Higuchi, Yuichi; Yoshida, Takashi; Kuma, Hiroyuki; Hamasaki, Naotaka; Mitsunaga, Masakazu; Kanzaki, Hisao; Kandori, Akihiko

    2012-02-01

    We characterized the magnetic markers used in biological immunoassays based on Brownian relaxation. Because the markers are composed of aggregated nanoparticles, i.e., magnetic nanoclusters, we first clarified their magnetic properties using AC susceptibility measurements, magnetization (M-H) curves, and magnetic relaxation properties. Analyzing the experimental results, we obtained the key parameters for the immunoassay, i.e., hydrodynamic diameter dh, magnetic moment mB, and anisotropy energy EB of the markers. Because these parameters were distributed in practical samples, we took their distribution into account in the analysis. Next, we showed the relationship between these parameters obtained from different samples. It was shown that mB increased approximately in proportion to dh. On the other hand, no clear correlation between mB and EB was obtained. These results were very different from those expected from single-domain nanoparticles and must be taken into account when magnetic markers are used in immunoassays based on Brownian relaxation.

  6. Fluorescence polarization immunoassays for monitoring nucleoside triphosphate diphosphohydrolase (NTPDase) activity.

    PubMed

    Fiene, Amelie; Baqi, Younis; Lecka, Joanna; Sévigny, Jean; Müller, Christa E

    2015-01-01

    The following members of the ecto-nucleoside triphosphate diphosphohydrolase family, NTPDase1 (CD39), NTPDase-2, -3, and -8, play an important role in purinergic signal transduction by regulating extracellular nucleotide levels. Potent and selective NTPDase inhibitors are required as pharmacological tools and have potential as novel drugs, e.g. for anti-cancer and anti-bacterial therapy. We have developed fast and sensitive NTPDase fluorescence polarization (FP) immunoassays using the natural substrates (ATP or ADP). During the NTPDase1-catalyzed reaction, the substrate is dephosphorylated to ADP which is further dephosphorylated yielding AMP as the final product (by NTPDase1). NTPDase3 and -8 yield AMP and ADP, while NTPDase2 results mainly in the formation of ADP. Direct quantification of the respective product, AMP or ADP, is achieved by displacement of an appropriate fluorescent tracer nucleotide from a specific antibody leading to a change in fluorescence polarization. The assays are highly sensitive and can be performed with low substrate concentrations (20 ?M ATP or 10 ?M ADP) below the KM values of NTPDases, which simplifies the identification of novel competitive inhibitors. Optimized antibody and enzyme concentrations allow the reproducible detection of 2 ?M ADP and 1 ?M AMP (at 10% substrate conversion). Validation of the assays yielded excellent Z'-factors greater than 0.70 for all investigated NTPDase subtypes indicating high robustness of the analytical method. Furthermore, we tested a standard inhibitor and performed a first exemplary screening campaign with a library consisting of >400 compounds (Z'-factor: 0.87, hit rate 0.5%). Thereby we demonstrated the suitability of the FP assay for IC50 value determination and high-throughput screening in a 384-well format. The new FP assays were shown to be superior to current standard assays. PMID:25372046

  7. Committee of Donor Agencies for Small Enterprise Development

    NSDL National Science Digital Library

    Established in 1979, the Committee of Donor Agencies promotes the development of small enterprise in developing countries. This site offers numerous working and research papers about the Committee of Donor Agencies and its members. Showcased on the site are the Committee's Donor Business Development Services Case Studies. The Case studies are browseable by several categories including Region, Country, Theme, and Member Agency. Also provided are the Donor Committee Guidelines and links to member agencies's sites.

  8. Using cheminformatics to predict cross reactivity of “designer drugs” to their currently available immunoassays

    PubMed Central

    2014-01-01

    Background A challenge for drug of abuse testing is presented by ‘designer drugs’, compounds typically discovered by modifications of existing clinical drug classes such as amphetamines and cannabinoids. Drug of abuse screening immunoassays directed at amphetamine or methamphetamine only detect a small subset of designer amphetamine-like drugs, and those immunoassays designed for tetrahydrocannabinol metabolites generally do not cross-react with synthetic cannabinoids lacking the classic cannabinoid chemical backbone. This suggests complexity in understanding how to detect and identify whether a patient has taken a molecule of one class or another, impacting clinical care. Methods Cross-reactivity data from immunoassays specifically targeting designer amphetamine-like and synthetic cannabinoid drugs was collected from multiple published sources, and virtual chemical libraries for molecular similarity analysis were built. The virtual library for synthetic cannabinoid analysis contained a total of 169 structures, while the virtual library for amphetamine-type stimulants contained 288 compounds. Two-dimensional (2D) similarity for each test compound was compared to the target molecule of the immunoassay undergoing analysis. Results 2D similarity differentiated between cross-reactive and non-cross-reactive compounds for immunoassays targeting mephedrone/methcathinone, 3,4-methylenedioxypyrovalerone, benzylpiperazine, mephentermine, and synthetic cannabinoids. Conclusions In this study, we applied 2D molecular similarity analysis to the designer amphetamine-type stimulants and synthetic cannabinoids. Similarity calculations can be used to more efficiently decide which drugs and metabolites should be tested in cross-reactivity studies, as well as to design experiments and potentially predict antigens that would lead to immunoassays with cross reactivity for a broader array of designer drugs. PMID:24851137

  9. Measurement of testosterone by immunoassays and mass spectrometry in mouse serum, testicular, and ovarian extracts.

    PubMed

    Handelsman, David J; Jimenez, Mark; Singh, Gurmeet K S; Spaliviero, Jenny; Desai, Reena; Walters, Kirsty A

    2015-01-01

    Accurate measurement of testosterone is important for reproductive endocrinology research, but the validity of direct (nonextraction) testosterone immunoassays, developed and validated for human serum, has not been appraised for application to mouse serum or steroidogenic tissue extracts. Testosterone was measured in serum and extracts of testis or ovary from male and female wild-type mice by 2 commercial direct testosterone immunoassays, with and without preassay extraction, and by the liquid chromatography, tandem mass spectrometry reference method. Results were compared hierarchically by correlation (Kendall's ?), regression (Passing-Bablok), and deviance (Bland-Altman) analysis, under the null hypothesis of perfect agreement between assays (slope = 1, intercept and deviation = 0). For mouse serum, immunoassays displayed an upward bias with performance better for male vs female sera and, within gender, improved by preassay extraction relative to liquid chromatography, tandem mass spectrometry. Testosterone was detectable in all serum samples, but few (male 54%, female 9%) were accurate (within 20% of the reference measurement). For mouse testis extracts, immunoassays were biased upwards, and preassay extraction improved immunoassay performance. Although testosterone was detectable in all extracts, a minority (45%) was accurate. For mouse ovary extracts, all correlations were poor with severe, upward bias, and while testosterone was detectable in all samples, virtually none were accurate. We conclude that these direct testosterone immunoassay kits provide relatively, but not absolutely, accurate results with male mouse serum and testis extracts but not with female mouse serum and ovary extracts, with performance improved by preassay extraction. Whether relative accuracy is fit for purpose depends on the experimental aims, design, and interpretation. PMID:25365769

  10. Donation from old living donors: how safe is it?

    PubMed

    Hourmant, Maryvonne; Lerat, Lydie; Karam, Georges

    2013-08-01

    As the rate of living kidney donor (LKD) transplantations increases, the selection of extended criteria donors such as old donors (>60-65 years) becomes more common. The pool of these old donors is probably wider than we think, especially if we tolerate a lower glomerular filtration rate (GFR) than the gold standard of 80 mL/min/1.73 m(2). Several important studies with large cohorts of living donors including old subjects have been published these last few years and give insights on the outcome in this subpopulation. The risk of death and end-stage renal disease (ESRD) is similar to that of matched controls from the general population. Post-donation GFR, as a result of glomerulopaenia, is lower in old than in younger donors but pre-donation as well as the rate of function loss is not different between young and old donors. Nearly 80% of donors over 60 have <60 mL/min GFR post-donation, the risk of cardiovascular mortality and progression to ESRD in the long term, as in the general population, is under question. Despite reduced renal function of the old kidney, the results of transplantation from an old living donor appeared to be equivalent to deceased transplantation from a younger donor. Finally, transplantation from an old living donor appeared to be a reasonably safe procedure for both the donor and the recipient and the age per se is certainly not a contraindication to donation. PMID:23543591

  11. Regret and Satisfaction as Determinants of Lapsed Donor Recommencement Decisions

    Microsoft Academic Search

    Roger Bennett

    2009-01-01

    Although a large amount of research has been undertaken into donor acquisition, relationship development, and the reasons why certain donors terminate their support for fundraising charities, few studies have examined the factors that encourage lapsed donors to resume giving to the organizations they have deserted. This empirical investigation sought to contribute to contemporary knowledge concerning this important matter via a

  12. The Dead Donor Rule: Can It Withstand Critical Scrutiny?

    Microsoft Academic Search

    Franklin G. Miller; R. D. Truog; D. W. Brock

    2010-01-01

    Transplantation of vital organs has been premised ethically and legally on “the dead donor rule” (DDR)—the requirement that donors are determined to be dead before these organs are procured. Nevertheless, scholars have argued cogently that donors of vital organs, including those diagnosed as “brain dead” and those declared dead according to cardiopulmonary criteria, are not in fact dead at the

  13. Kidneys from Dead Older Donors May Help Seniors, Study Finds

    MedlinePLUS

    ... donor right away, rather than waiting for an organ from a younger donor. The study was published online March 26 in the Journal of the American Society of Nephrology . "Older patients derive a survival benefit from rapid transplantation with an older donor kidney, while younger patients ...

  14. The infrared fingerprint signals of silica nanoparticles and its application in immunoassay

    NASA Astrophysics Data System (ADS)

    Ding, Yadan; Chu, Xueying; Hong, Xia; Zou, Peng; Liu, Yichun

    2012-01-01

    Infrared absorption properties of silica nanoparticles were studied. The transverse optical and the longitudinal optical phonon modes from the silica were proved to be the characteristic spectroscopic fingerprint signals. Based on this, a sandwich-structured immunoassay was performed, and the detection of the analyte (human IgG) was achieved by using biofunctional silica nanoparticles as infrared probes. The immunoassay based on Fourier transform infrared reflection absorption spectroscopy of silica nanoparticles shows significant value for potential applications in many areas, such as biomedicine, food safety, and waste treatment.

  15. Detection of CBW agents and explosives with an immunoassay film badge

    SciTech Connect

    Lukens, H.R. [Diametrix Detectors, Inc., San Diego, CA (United States)

    1993-12-31

    In this work, a small, dry immunoassay film badge (IFB) is shown to be feasible for the detection of vapor from explosives and toxic compounds. The IFB retains the unique specificity and sensitivity that characterizes immunoassays, but achieves fieldable simplicity and convenience by avoiding wet chemistry. The capacity of the IFB is sufficient to allow repeated use. Data indicate that IFBs can be developed to respond in a few seconds to parts-per-trillion levels of vapor, especially in dynamically acquired samples of air.

  16. Donor morbidity associated with right lobectomy for living donor liver transplantation to adult recipients: A systematic review

    Microsoft Academic Search

    Kimberly L. Beavers; Robert S. Sandler; Roshan Shrestha

    2002-01-01

    The aim if this study is to determine donor morbidity associated with right lobectomy for living donor liver transplantation (LDLT) to adult recipients through a systematic review of the published literature. Data sources were English-language reports on donor outcome after LDLT. MEDLINE (1995 to June 2001) was searched using the MeSH terms [ldquo ]living donors[rdquo ] and [ldquo ]liver transplantation.[rdquo

  17. Donor Complications Including the Report of One Death in Right-Lobe Living-Donor Liver Transplantation

    Microsoft Academic Search

    Julio C. U. Coelho; Alexandre C. T. de Freitas; Jorge E. F. Matias; José Luiz de Godoy; Clementino Zeni Neto; Mônica B. Parolin; Luciano Okawa

    2007-01-01

    Background\\/Aims: Our objective is to assess donor complications in all right hepatic lobe living-donor liver transplantation (LDLT) at our center. Methods: Of a total of 352 liver transplantations performed, 60 were right-lobe LDLT. Most donors (88.3%) were related to the recipients. Results: Mean hospital stay was 5.4 8 0.6 days. No complications occurred due to preoperative evaluation. Most donors received

  18. Diet and Asthma: Vitamins and Methyl Donors

    PubMed Central

    Han, Yueh-Ying; Blatter, Josh; Brehm, John M.; Forno, Erick; Litonjua, Augusto A; Celedón, Juan C.

    2014-01-01

    SUMMARY Dietary changes may partly explain the high burden of asthma in industrialized nations. Experimental studies have motivated a significant number of observational studies of the relation between vitamins (A, C, D, and E) or nutrients acting as methyl donors (folate, vitamin B12, and choline) and asthma. Because observational studies are susceptible to several sources of bias, well-conducted randomized controlled trials (RCTs) remain the “gold standard” to determine whether a vitamin or nutrient has an effect on asthma. Evidence from observational studies and/or relatively few RCTs most strongly justify ongoing and future RCTs of: 1) vitamin D to prevent or treat asthma, 2) choline supplementation as adjuvant treatment for asthma, and 3) vitamin E to prevent the detrimental effects of air pollution in subjects with asthma. At this time, there is insufficient evidence to recommend supplementation with any vitamin or nutrient acting as a methyl donor to prevent or treat asthma. PMID:24461761

  19. Strategies of the donor search for children with second CR ALL lacking a matched sibling donor.

    PubMed

    Lanino, E; Sacchi, N; Peters, C; Giardino, S; Rocha, V; Dini, G

    2008-06-01

    During the last 10 years, the number of alternative Haematopoietic stem cell transplantations (HSCTs) performed on children in Europe has increased significantly and has reached 61% of the allografts. In this paper, we provide practical guidelines to help define an algorithm for the treatment of children relapsing during or after first-line chemotherapy for ALL and lacking a matched sibling donor. A simultaneous search for an unrelated donor and for a cord blood unit should be started. This study focuses mainly on the effects of some factors on survival in an effort to highlight the influence that these factors have on our choices. Matching the patient for HLA-A, -B, -C and -DRB1 alleles remains the top priority: a single HLA class I or II allele mismatch has no influence on survival, while multiple mismatching for more than one class I allele and simultaneous disparities in class I and II alleles increase mortality. The impact of additional mismatches for HLA-DQ and -DP loci on survival is still controversial. Young donor age is the most important factor that has a significant effect on better survival from among several other factors, including CMV sero-status, gender and ABO. An 18- to 30-year-old, 8/8 allele-matched donor (excluding allele matching at DQB1) or for many teams 10/10 allele-matched donor; or a 4 out of 6 (considering Ag HLA-A, -B and allelic typing of DRB1) CB unit containing more than 3.0 x 10(7) nuclear cells is considered by most institutions. The choice should be made on the basis of urgency. If a donor or a CB unit is not found within an appropriate time frame, generally less than 3 months after obtention of remission, haploidentical HSCT should be offered. Some institutions consider haploidentical HSCT the second therapeutic option when a matched donor is not available. PMID:18545249

  20. 78 FR 66366 - Draft Guidance for Industry: Use of Donor Screening Tests To Test Donors of Human Cells, Tissues...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-05

    ...Screening Tests To Test Donors of Human Cells, Tissues, and Cellular and Tissue-Based...Screening Tests to Test Donors of Human Cells, Tissues, and Cellular and Tissue-Based...Eligibility Determination for Donors of Human Cells, Tissues, and Cellular and...

  1. Donor symptomatology and safety in blood cell separation procedures.

    PubMed

    Hester, J P

    1982-01-01

    Increasing demands for platelet and granulocyte concentrates collected by cell separation technology for replacement strategies requires expanding available donor pools, related or unrelated by recruiting additional donors or increasing the frequency with which a donor is processed. The expanding application of cell separation devices for plasma or red cell exchange as a therapeutic modality for many medical diagnoses now exposes patients with altered physiology to technology and procedures originally designed for healthy blood component donors. Some possible risks from the technology and/or procedure are discussed. Donor symptomatology from the chemical agents used in blood processing and a relationship to scheduling frequency are introduced. PMID:6179100

  2. Computer applications in the search for unrelated stem cell donors.

    PubMed

    Müller, Carlheinz R

    2002-08-01

    The majority of patients which are eligible for a blood stem cell transplantation from an allogeneic donor do not have a suitable related donor so that an efficient unrelated donor search is a prerequisite for this treatment. Currently, there are over 7 million volunteer donors in the files of 50 registries in the world and in most countries the majority of transplants are performed from a foreign donor. Evidently, computer and communication technology must play a crucial role in the complex donor search process on the national and international level. This article describes the structural elements of the donor search process and discusses major systematic and technical issues to be addressed in the development and evolution of the supporting telematic systems. The theoretical considerations are complemented by a concise overview over the current state of the art which is given by describing the scope, relevance, interconnection and technical background of three major national and international computer appliances: The German Marrow Donor Information System (GERMIS) and the European Marrow Donor Information System (EMDIS) are interoperable business-to-business e-commerce systems and Bone Marrow Donors World Wide (BMDW) is the basic international donor information desk on the web. PMID:12216954

  3. Monoclonal antibody-based broad-specificity immunoassay for monitoring organophosphorus pesticides in environmental water samples

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The extensive use of organophosphorus pesticides (OPs) in agriculture and domestic settings can result in widespread water contamination. The development of easy-to-use and rapid-screening immunoassay methods in a class-selective manner is a topic of considerable environmental interest. In this wo...

  4. The measurement of triclosan in water using a magnetic particle enzyme immunoassay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A sensitive magnetic particle-based immunoassay to determine triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) in drinking water and wastewater was developed. Rabbit antiserum was produced by immunizing the rabbit with 6-(5-chloro-2-(2,4-dichlorophenoxy)phenoxy)hexanoic acid-keyhole limpet hemocya...

  5. IMMUNOASSAY METHODS FOR MEASURING ATRAZINE AND 3,5,6-TRICHLORO-2-PYRIDINOL IN FOODS

    EPA Science Inventory

    This chapter describes the use of enzyme-linked immunosorbent assay (ELISA) methods for the analysis of two potential environmental contaminants in food sample media, atrazine and 3,5,6-trichloro-2-pyridinol (3,5,6-TCP). Two different immunoassay formats are employed: a magnetic...

  6. Evaluation of a new chemiluminescence immunoassay for laboratory diagnosis of syphilis.

    PubMed

    Sampedro-Martinez, A; Padilla-Malo, A; Gomez-Camarasa, C; Rodriguez-Granger, J; Lara-Oya, A

    2013-08-01

    The purpose of this study was to evaluate diagnostic performances of automated chemiluminescence immunoassay (CLIA) in comparison with Treponema pallidum hemagglutination test (TPHA). The specificity of CLIA was 98.9% and 99.6% for TPHA, whereas the sensitivity was 98% and 96%, respectively. Considering the suitability for automation, CLIA may represent a suitable alternative. PMID:23732753

  7. A fluorescence polarization immunoassay for the detection of zearalenone in corn

    Microsoft Academic Search

    Hyang Sook Chun; Eun Hye Choi; Hyun-Joo Chang; Sung-Wook Choi; Sergey A. Eremin

    2009-01-01

    The aim of this study was to develop a fluorescence polarization immunoassay (FPIA) that is based on the change in fluorescence polarization of fluorescently labeled small antigen when bound by a specific antibody, for use as a screening test for zearalenone (ZEN) in cereals and their products. Syntheses of fluorescein-labeled ZEN tracers containing three linkers of different lengths (2, 3

  8. Development of a fluorescence polarization immunoassay (FPIA) for the quantitative determination of paclitaxel

    Microsoft Academic Search

    C. Bicamumpaka; M. Pagé

    1998-01-01

    We have developed a fluorescence polarization immunoassay (FPIA) for the quantitative determination of paclitaxel in serum, crude Taxus extracts and Erwinia taxi culture medium. To achieve this, we used an antipaclitaxel monoclonal antibody and an FITC-labeled paclitaxel. Paclitaxel was chemically modified by introducing an amino function to enable coupling with fluorescein isothiocyanate. Paclitaxel competitively inhibited the binding of the monoclonal

  9. Multiplex Immunoassay for Serological Diagnosis of Mycobacterium bovis Infection in Cattle

    Microsoft Academic Search

    Clare Whelan; Eduard Shuralev; Grainne O'Keeffe; Paula Hyland; Hang Fai Kwok; Philip Snoddy; Amanda O'Brien; Marie Connolly; Padraig Quinn; Matt Groll; Todd Watterson; Sara Call; Kevin Kenny; Anthony Duignan; Mary Jo Hamilton; Bryce M. Buddle; James A. Johnston; William C. Davis; Shane A. Olwill; John Clarke

    2008-01-01

    Efforts to develop a better diagnostic assay for bovine tuberculosis have shown that the sensitivity and specificity of an assay can be improved by the use of two or more antigens. As reported here, we developed a multiplex chemiluminescent immunoassay that can simultaneously detect antibody activity to 25 antigens in a single well in a 96-well plate array format. The

  10. Phage-Displayed Peptide That Mimics Aflatoxins and Its Application in Immunoassay

    E-print Network

    Hammock, Bruce D.

    Phage-Displayed Peptide That Mimics Aflatoxins and Its Application in Immunoassay Yanru Wang as a coating antigen in aflatoxin detection by an ELISA method, a random-8-peptide library was constructed and used as a source of peptides that mimic aflatoxins (termed as mimotopes). Five mimotope peptides were

  11. AUTOMATED FLOW FLUORESCENT IMMUNOASSAY FOR PART PER TRILLION DETECTION OF THE NEONICOTINOID INSECTICIDE THIAMETHOXAM.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An ultra sensitive automated flow fluorescent immunoassay was developed using the KinExATM 3000 system for quantitative analysis of the neonicotinoid insecticide thiamethoxam. Five monoclonal antibodies were obtained and screened with a competitive ELISA. One monoclonal antibody designated as E6VI ...

  12. Detection of Helicobacter pylori in Stool Specimens by PCR and Antigen Enzyme Immunoassay

    Microsoft Academic Search

    ATHANASIOS MAKRISTATHIS; EVA PASCHING; KURT SCHUTZE; MARGIT WIMMER; MANFRED L. ROTTER; ALEXANDER M. HIRSCHL

    1998-01-01

    A highly sensitive seminested PCR assay to detect Helicobacter pylori DNA in feces was developed. PCR with stool specimens and a novel antigen enzyme immunoassay (EIA) for H. pylori detection in feces were evaluated as diagnostic tools and in follow-up with samples from 63 infected and 37 noninfected persons. Infected individuals received eradication therapy followed by endoscopic follow-up 35 days

  13. A commercial rapid optical immunoassay detects Streptococcus agalactiae from aquatic cultures and clinical specimens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The BioStar STREPT B Optical ImmunoAssay (OIA) (BioStar® OIA® Strep B Assay Kit; Biostar Incorporation; Louisville, CO, USA) was used to identify 32 known group B streptococcus (GBS) isolates of fish, dolphin, bovine, and human origin. Thirteen non-GBS isolates from fish and other animals were test...

  14. Rapid detection of group B streptococcal colonization of the genital tract by a commercial optical immunoassay

    Microsoft Academic Search

    K. C. Carroll; D. Ballou; M. Varner; H. Chun; R. Traver; J. Salyer

    1996-01-01

    The performance of a commercial optical immunoassay (OIA) was compared at two institutions with that of routine agar and broth culture methods for the detection of group B streptococcal (GBS) colonization of the genital tract. The Strep B OIA (Bio Star, USA) was used to test 962 vaginal swabs from pregnant women for the presence of GBS antigen. The prevalence

  15. Detection of Group B Streptococcus by immunoassay following enrichment in LIM-selective broth medium

    Microsoft Academic Search

    Judith S. Heelan; Cecile Letourneau; Dorothy Lamarche

    1995-01-01

    Rapid immunoassays have been developed to decrease the time to detection of Group B Streptococcus (GBS) carriage in pregnant women. In this study, a total of 162 pregnant women, considered to be high-risk obstetric patients, were seen in the Family Care Center at Memorial Hospital of Rhode Island, a 300-bed teaching hospital associated with Brown University Medical School. Vaginal and

  16. Quantum dot-based immunoassay enhanced by high-density vertical ZnO nanowire array.

    PubMed

    Kim, Jung; Kwon, Seyong; Park, Je-Kyun; Park, Inkyu

    2014-05-15

    In this paper, we report an efficient and high-performance immunoassay platform by combining high-density vertical ZnO nanowire array with photostable quantum dot (QD) labeling. The ZnO nanowire array provides a large surface area for the immobilization of biomolecules, which makes it an efficient substrate for the immunoreaction of biomolecules. When a sandwich immunoassay with QD label was conducted on various substrates, the ZnO nanowire substrate showed stronger fluorescence signal than ZnO thin film and bare glass substrates by 3.8 and 8.5 times, respectively. We found that the fluorescence resonance energy transfer (FRET) from QD to ZnO nanowire could be suppressed by extending their distance with multilayer biotin-streptavidin complex. In addition, we demonstrated the QD-based immunoassay of carcinoembryonic antigen (CEA) on a ZnO nanowire substrate, showing an excellent immunoassay performance with a very low detection limit (0.001 ng/mL) and a large detection range up to 100 ng/mL. PMID:24384261

  17. Immunochemical techniques for environmental analysis II. Antibody production and immunoassay development

    Microsoft Academic Search

    Shirley Gee; Bruce D. Hammock

    1995-01-01

    Antibody production is the key step of any immunochemical technique. The antibody determines to a large extent the specificity and sensitivity of the resulting immunochemical technique. These features may be modulated by judicious design of the immunogen and by rational immunoassay development. Criteria for hapten design and the steps involved in the obtention of antibodies and the development of competitive

  18. Synthesis of Haptens and Derivation of Monoclonal Antibodies for Immunoassay of the Phenylurea Herbicide Diuron

    Microsoft Academic Search

    Alexander E. Karu; Marvin H. Goodrow; Douglas J. Schmidt; Bruce D. Hammock; Michael W. Bigelow

    1994-01-01

    Diuron and related phenylurea herbicides and their metabolites are important candidates for sensitive and specific immunodetection. This paper describes a scheme for the synthesis of two different types of phenylurea haptens for immunization and use as detecting conjugates in enzyme immunoassays (EIAs). The haptens were used to develop indirect and direct EIAs and to derive a panel of monoclonal antibodies

  19. Comparison of salivary cortisol as measured by different immunoassays and tandem mass spectrometry.

    PubMed

    Miller, Robert; Plessow, Franziska; Rauh, Manfred; Gröschl, Michael; Kirschbaum, Clemens

    2013-01-01

    Assessing the amount of bioavailable cortisol in saliva with immunoassays and thus sampling an endocrine marker of hypothalamus-pituitary-adrenal axis activity is of major interest in both research and clinical practice. However, absolute cortisol concentrations obtained with different immunoassays (IAs) are barely comparable precluding direct comparison between studies or individuals whenever cortisol analyses were not based on the same IA. The present technical report aims to solve this problem by evaluating the validity of, as well as agreement between the most commonly used immunoassays in psychoneuroendocrinological research (i.e., IBL, DRG, Salimetrics, DSL, and DELFIA) and a reference method (LC-MS/MS) in a sample of 195 saliva specimen covering the whole range of cortisol concentrations in adults. A structural equation modelling framework is applied to decompose systematic assay variance and estimate cortisol reference values, which are adjusted for measurement error and interference of salivary cortisone. Our findings reveal nonlinear relations between IAs and LC-MS/MS, which are discussed in terms of IA cross-reactivity with saliva matrix components. Finally guidelines for converting cortisol concentrations being obtained by these immunoassays into comparable reference values are proposed by providing conversion functions, a conversion table, and an online conversion tool. PMID:22641005

  20. Enhanced Sensitive Immunoassay: Noncompetitive Phage Anti-Immune Complex Assay for the Determination of Malachite Green

    E-print Network

    Hammock, Bruce D.

    for the Determination of Malachite Green and Leucomalachite Green Jie-Xian Dong,, Chao Xu, Hong Wang,*, Zhi-Li Xiao ABSTRACT: To develop a more sensitive immunoassay for malachite green (MG) and leucomalachite green (LMG for monitoring food safety. KEYWORDS: malachite green, leucomalachite Green, phage anti-immunocomplex assay

  1. Microarray Immunoassay for Phenoxybenzoic Acid Using Polymer Encapsulated Eu:Gd2O3

    E-print Network

    Hammock, Bruce D.

    Microarray Immunoassay for Phenoxybenzoic Acid Using Polymer Encapsulated Eu:Gd2O3 Nanoparticles). The amino functionalization of the par- ticles was achieved by poly(L-lysine) (PL) encapsulation nanostructures (polymer beads, fluorophore-doped nanoparticles, semiconductor quantum dots, inorganic and organic

  2. Species cross-reactivity of rheumatoid factors and implications for immunoassays.

    PubMed

    Holm, Bettina E; Sandhu, Noreen; Tronstrøm, Julie; Lydolph, Magnus; Trier, Nicole H; Houen, Gunnar

    2015-01-01

    Rheumatoid factors (RFs) are antibodies recognizing other antibodies usually by binding to the Fc part, while heterophilic antibodies (HAbs) are antibodies reacting with immunoglobulins (Igs) from other species. In particular, RFs have been found to cause false positive results in sandwich immunoassays. In this work, we analyzed RF-positive and RF-negative sera for content of cytokines and for heterophilic reactions by enzyme-linked immunosorbent assay and bead-based sandwich immunoassays. All sera, including those with RFs, contained insignificant amounts of cytokines and chemokines, but RF-positive sera showed large false positive values for several cytokines when analyzed by fluorescent bead-based multiplex immunoassays. This non-specific binding could be minimized by reagents designed to block HAbs, i.e. by selected animal IgGs. Furthermore, sera positive for RFs reacted with several animal IgGs, when these were immobilized on beads or coated on the polystyrene surface in enzyme-linked immunosorbent assays. This reaction could be inhibited by human IgG and by agents designed to inhibit heterophilic reactions (i.e. mixtures of IgGs from different species). In conclusion, RFs and HAbs represent an identical/overlapping set of antibodies, causing false positive reactions in sandwich and other immunoassays. Such assays must be conducted in the presence of appropriate blocking agents, e.g. HBR+, and must be carefully controlled. PMID:25347362

  3. The diagnostic power of direct carbohydrate-deficient transferrin immunoassay in alcoholics. Absolute or relative values?

    Microsoft Academic Search

    Lech Chrostek; Bogdan Cylwik; Ewa Gruszewska; Jolanta Tobolczyk

    The objective of this study was to compare the diagnostic power of direct carbohydrate-deficient transferrin (CDT) immunoassay in alcohol abuse expressed in relative units with the diagnostic power of the results expressed in absolute units. Serum CDT was determined in 127 alcoholics using N Latex CDT direct immunonephelometric assay (Siemens Healthcare Diagnostics, Marburg, Germany). The diagnostic sensitivity, specificity, negative and

  4. Quantitative determination of nuclear estrogen receptors by an enzyme immunoassay: applicability and caveats.

    PubMed

    Kral, L G; Doherty, L M; Brooks, S C

    1988-10-01

    A method is presented with which approx. 95% of nuclear estrogen receptors appear to be extracted from MCF-7 cells. Since both nuclear isolation and nuclear estrogen receptor extraction take place in a single test tube with only vortex mixing, loss of nuclear material is minimized. The amount of nuclear estrogen receptors in the nuclear extract was determined by direct [3H]estradiol labeling of monolayer cultures and with a commercially available estrogen receptor immunoassay (ER-EIA) kit. Since the ER-EIA kit was designed and calibrated for quantitative determination of cytosolic estrogen receptor isolated in low ionic strength buffer, the applicability of the ER-EIA to quantitative determination of estrogen receptor content in high ionic strength nuclear extraction buffer was tested. A linear relationship exists between the amount of nuclear estrogen receptor detected by the immunoassay, the amount of receptor present in serial dilutions of the nuclear extract and the amount of nuclear estrogen receptor detected in cells by [3H]estradiol labeling of monolayer cultures, the absolute amount of nuclear estrogen receptors determined by the immunoassay consistently exceeded the amount of receptor detected by [3H]estradiol labeling. The possibility that the enzyme immunoassay must be properly calibrated for the specific conditions of the nuclear estrogen receptor assay is discussed. PMID:3050279

  5. Functionalized Europium Oxide Nanoparticles Used as a Fluorescent Label in an Immunoassay

    E-print Network

    Hammock, Bruce D.

    Functionalized Europium Oxide Nanoparticles Used as a Fluorescent Label in an Immunoassay properties that are typical of europium, that is, a spectrally narrow, red emission and a long fluorescence may be based on lanthanide-derived phosphors. For example, the optical properties of europium chelates

  6. Development of an electrochemical immunoassay for detection of gatifloxacin in swine urine*

    PubMed Central

    Yi, Jian; Meng, Meng; Liu, Zhong-qiu; Zhi, Jin-fang; Zhang, Yuan-yang; Xu, Jing; Wang, Ya-bin; Liu, Jin-ting; Xi, Ri-mo

    2012-01-01

    To detect gatifloxacin (GAT) residue in swine urine, an electrochemical immunoassay was established. An indirect competitive immunoassay was developed, in which the coating antigen is immobilized in an enzyme-linked immunosorbent assay (ELISA) plate and GAT residue from the sample competes with the limited binding sites in added anti-GAT antibody. Horseradish peroxidase (HRP) conjugated to goat anti-rabbit IgG was used as the enzymatic label. A carbon fiber working electrode was constructed and current signals were detected by using hydrogen peroxide as a substrate and hydroquinone as an electrochemical mediator. The electrochemical immunoassay was evaluated by analysis of GAT in buffer or swine urine and an average value of half inhibition concentration (IC50) of 8.9 ng/ml was obtained. Excellent specificity of the antibody was achieved with little cross-reaction with lomefloxacin (3.0%), ciprofloxacin (3.0%), and ofloxacin (1.9%) among commonly used (fluoro)quinolones. In conclusion, the immunoassay system developed in this research can be used as a rapid, powerful and on-site analytical tool to detect GAT residue in foods and food products. PMID:22302425

  7. Enzyme-Labeling of Antibodies and Their Fragments for Enzyme Immunoassay and Immunohistochemical Staining

    Microsoft Academic Search

    Eiji Ishikawa; Masayoshi Imagawa; Seiichi Hashida; Shinji Yoshitake; Yoshitaka Hamaguchi; Tetsuo Ueno

    1983-01-01

    The use of an enzyme as a label has a number of advantages over the use of other labels in both immunohistochemistry and immunoassay. Immunofluorescence techniques are not suitable for ultrastructural research on cells, and ferritin-labeled antibodies allow only electronmicroscopic studies. By contrast, enzyme-labeled antibodies permit localization of cellular antigens in relation to tissue structures under light microscope and also

  8. Competitive homogeneous digoxigenin immunoassay based on fluorescence quenching by gold nanoparticles

    Microsoft Academic Search

    Sergiy Mayilo; Benjamin Ehlers; Michael Wunderlich; Thomas A. Klar; Hans-Peter Josel; Dieter Heindl; Alfons Nichtl; Konrad Kürzinger; Jochen Feldmann

    2009-01-01

    We report on a competitive, homogeneous immunoassay for the detection of the hapten digoxigenin. The assay is based on competitive fluorescence quenching by gold nanoparticles. Digoxigenin is indirectly labeled with the fluorophore Cy3B through bovine serum albumin and used as a marker. Gold nanoparticles functionalized with anti-digoxigenin antibodies serve as fluorescence quenchers. Free digoxigenin molecules in the analyte solution compete

  9. Application and validation of polybrominated diphenyl ethers immunoassay for environmental and food matrices.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A sensitive magnetic particle enzyme-linked immunoassay (ELISA) was developed to analyze polybrominated diphenyl ethers (PBDEs) in water, milk, fish, chicken and soil samples. The assay is rapid and can be used to analyze fifty samples in about one hour after sample cleanup. The assay has a limit ...

  10. Production of anti-idiotype antibodies for deoxynivalenol and their evaluation with three immunoassay platforms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immunoassays for deoxynivalenol (DON) that involve the competition for binding to DON-specific antibodies have been widely developed. In such assays, the responses of samples are generally compared to calibration curves generated by using DON in competition with labeled reagents such as enzymatic or...

  11. IMMUNOASSAY METHOD FOR THE DETERMINATION OF PENTACHLOROPHENOL IN SOIL AND SEDIMENT

    EPA Science Inventory

    The journal article describes the use of a prototype immunoassay method for the determination of pentacholorphenol (PCP) in soil and sediment. PCP was used as a pesticide and wood preservative and is not currently available to the general public. The paper stresses the importan...

  12. Theoretical analysis of a magnetophoresis-diffusion T-sensor immunoassay.

    PubMed

    Forbes, Thomas P; Munson, Matthew S; Forry, Samuel P

    2013-10-01

    We present the analytical investigation of a microfluidic homogeneous competitive immunoassay that incorporates antibody-conjugated superparamagnetic nanoparticles and magnetophoretic transport to enhance the limits of detection and dynamic range. The analytical model considers the advective, diffusive, and magnetophoretic transport of the antibody-coated nanoparticles relative to the labeled and sample antigens of interest in a T-sensor configuration. The magnetophoresis-diffusion immunoassay identified clear improvements to the assay response and reductions to the limit of detection for increased magnetophoretic velocities and larger nanoparticles. The externally applied magnetophoretic transport enriched the antibody-antigen accumulation region, while larger nanoparticles led to decreased diffusive peak broadening. The integration of nanoparticles to the diffusion immunoassay (NP-DIA) demonstrated an approximately 3-fold improvement to the limit of detection of the basic antibody/antigen system, while the integration of superparamagnetic nanoparticles and magnetophoretic transport (MIA) established an order of magnitude improvement in sensitivity as well as means to greatly reduce response time. The implementation of an external magnetic force enabled the detectable antigen size spectrum to extend from small molecules i.e., 10's Da to 100's Da, up to large proteins and macromolecules, i.e., 50 kDa to 150 kDa, for a single class of binding species, i.e., superparamagnetic nanoparticle. This investigation provides guidelines for the design and development of a magnetophoresis-diffusion T-sensor immunoassay, and clearly identifies the regimes for optimal operation. PMID:23945824

  13. Automated digital microfluidic platform for magnetic-particle-based immunoassays with optimization by design of experiments.

    PubMed

    Choi, Kihwan; Ng, Alphonsus H C; Fobel, Ryan; Chang-Yen, David A; Yarnell, Lyle E; Pearson, Elroy L; Oleksak, Carl M; Fischer, Andrew T; Luoma, Robert P; Robinson, John M; Audet, Julie; Wheeler, Aaron R

    2013-10-15

    We introduce an automated digital microfluidic (DMF) platform capable of performing immunoassays from sample to analysis with minimal manual intervention. This platform features (a) a 90 Pogo pin interface for digital microfluidic control, (b) an integrated (and motorized) photomultiplier tube for chemiluminescent detection, and (c) a magnetic lens assembly which focuses magnetic fields into a narrow region on the surface of the DMF device, facilitating up to eight simultaneous digital microfluidic magnetic separations. The new platform was used to implement a three-level full factorial design of experiments (DOE) optimization for thyroid-stimulating hormone immunoassays, varying (1) the analyte concentration, (2) the sample incubation time, and (3) the sample volume, resulting in an optimized protocol that reduced the detection limit and sample incubation time by up to 5-fold and 2-fold, respectively, relative to those from previous work. To our knowledge, this is the first report of a DOE optimization for immunoassays in a microfluidic system of any format. We propose that this new platform paves the way for a benchtop tool that is useful for implementing immunoassays in near-patient settings, including community hospitals, physicians' offices, and small clinical laboratories. PMID:23978190

  14. Assessment of Platelia Aspergillus enzyme immunoassay for the diagnosis of invasive aspergillosis

    Microsoft Academic Search

    Chih-Cheng Lai; Hsiao-Leng Hsu; Li-Na Lee; Po-Ren Hsueh

    Background and Purpose: This study investigated the diagnostic value of Platelia Aspergillus enzyme immunoassay (EIA) for galactomannan (GM) antigen in patients at risk of invasive aspergillosis (IA), and its association with clinical course and outcome. Methods: A total of 304 blood samples were collected from 189 patients at risk of IA during a 1-year period at a tertiary referral center.

  15. An immunoassay method for quantitative detection of proteins using single antibodies

    Microsoft Academic Search

    Shengliang Zhou; Xiaojuan Lu; Caifa Chen; Dongxu Sun

    2010-01-01

    A new immunoassay method called specific analyte labeling and recapture assay (SALRA) to quantitatively measure protein abundance was developed, and the assay conditions were optimized. The key features of this method include labeling the antigen bound to the capture antibody, eluting the labeled antigen, and recapturing it by the same capture antibody on the detection plate. The reporter molecules on

  16. A 7-plex microbead-based immunoassay for serotyping Shiga toxin-producing Escherichia coli

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Serotyping of Shiga toxin-producing Escherichia coli (STEC) has been contingent upon the availability of antisera. Here we describe a 7-plex microbead-based immunoassay to simultaneously serotype seven STEC (i.e., belonging to serogroups O26, O45, O103, O111, O121, O145, and O157) by the Luminex xMA...

  17. DEVELOPMENT OF A FLUORESCENT LATEX IMMUNOASSAY FOR DETECTION OF SPECTINOMYCIN ANTIOBIOTIC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spectinomycin is an antimicrobial agent used to treat infections caused by Gram negative and positive microorganisms in poultry, swine and non-lactating cattle. There is a need to develop a rapid and sensitive method to detect spectinomycin residues in animal tissues. A latex fluorescent immunoassay...

  18. Analytica Chimica Acta 534 (2005) 109120 Development of a class selective immunoassay for

    E-print Network

    Hammock, Bruce D.

    for tolerance to co-solvent, pH and ionic strength changes. The IC50s of the optimized immunoassay were 78 g l-1 advantages to the agricultural ecosystem if used carefully, but have a potential for environ- mental damage, a sensitive, selective, and rapid method for monitoring residue levels of pyrethroids in aquatic ecosys- tems

  19. ENZYME-LINKED IMMUNOASSAYS FOR THE DETECTION OF MICROBIAL ANTIGENS AND THEIR ANTIBODIES

    EPA Science Inventory

    The advantages of enzyme-immunoassay (EIA) over radioactive assay techniques are mainly convenience in use, in that the labelled immunoreagents are stable for long periods, and the precautions and disposal procedures required for radioisotopes are unnecessary. In addition, the us...

  20. Development and testing of radio and enzyme immunoassays for acidic fibroblast growth factor (aFGF)

    SciTech Connect

    Caruelle, D.; Grassi, J.; Courty, J.; Groux-Muscatelli, B.; Pradelles, P.; Barritault, D.; Caruelle, J.P.

    1988-09-01

    Acidic fibroblast growth factor (aFGF) and basic fibroblast growth factor from bovine brain stimulate growth in a variety of tissues in several species. Despite the 55% amino acid sequence homology of the two forms of FGF, a specific immunoassay of aFGF has been developed using a polyclonal antibody raised in a rabbit. Two immunoassays were compared: a radioimmunoassay (RIA) using /sup 125/I aFGF and an enzyme immunoassay (EIA) using aFGF coupled to the tetrameric form of acetylcholinesterase (aFGF-AchE) as tracer. With EIA, the detection limit was 1.5 ng/ml, versus 2.2 ng/ml with RIA, while the dose at 50% was 5.9 ng/ml for EIA and 9.6 ng/ml for RIA. Using a modified EIA procedure where aFGF-AchE was added 2 h after the other reagents, the dose at 50% binding was 1.5 ng/ml. Examples of the performance of both immunoassays are presented for various brain extracts of different species including human. The aFGF content obtained by these methods correlates (CR = 0.987) with the values obtained by biological assay.

  1. Competitive chemiluminescent anzyme immunoassay for vitamin B12 analysis in human milk.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent discoveries of matrix interferences by haptocorrin (HC) in human milk and serum show that past analyses of vitamin B12 in samples with high HC content might have been inaccurate (Lildballe et al., 2009; Carmel & Agrawal, 2012). We evaluated two competitive enzyme-binding immunoassays for seru...

  2. Highly Sensitive, Automated Immunoassay for Immunoglobulin Free Light Chains in Serum and Urine

    Microsoft Academic Search

    Arthur R. Bradwell; Hugh D. Carr-Smith; Graham P. Mead; Lian X. Tang; Paul J. Showell; Mark T. Drayson; Roger Drew

    Background: Bence Jones proteins or monoclonal im- munoglobulin k and l free light chains (FLCs) are important markers for identifying and monitoring many patients with B-cell tumors. Automated immunoassays that measure FLCs in urine and serum have consider- able clinical potential. Methods: Sheep antibodies, specific for FLCs, were prepared by immunization with pure k and l molecules and then adsorbed

  3. Evaluation of a new enzyme immunoassay for detecting Helicobacter pylori in feces: a prospective pilot study

    Microsoft Academic Search

    Lucio Trevisani; Sergio Sartori; Fabrizio Galvani; Maria Rita Rossi; Marco Ruina; Carlo Chiamenti; Michele Caselli

    1999-01-01

    OBJECTIVE: There is an increasing interest in noninvasive tests for detecting Helicobacter pylori (H. pylori) infection. Unlike serological and urea breath tests, the possibility of searching for H. pylori in feces has been scarcely investigated. The aim of this prospective pilot study was to evaluate the usefulness of a new enzyme immunoassay for detecting H. pylori antigens in feces, as

  4. Heparin interferes with the radioenzymatic and homogeneous enzyme immunoassays for aminoglycosides

    SciTech Connect

    Krogstad, D.J. (Barnes Hospital, St. Louis, MO); Granich, G.G.; Murray, P.R.; Pfaller, M.A.; Valdes, R.

    1981-07-01

    Heparin interferes with measurement of aminoglycosides in serum by biological, radioenzymatic, and homogeneous enzyme immunoassay techniques, but not with radioimmunoassay. At concentrations greater than or equal to 10/sup 5/ and greater than or equal to 3 X 10/sup 6/ USP units/L, respectively, it interferes with the radioenzymatic assay by inhibiting the gentamicin 3-acetyltransferase and kanamycin 6'-acetyltransferase enzymes used in the assay. It interferes with the homogeneous enzyme immunoassays for gentamicin and tobramycin (at concentrations greater than or equal to 10/sup 5/ and greater than or equal to10/sup 4/ USP units/L, respectively), but not with the commercially available homogeneous enzyme immunoassays for other drugs. Heparin interference with the homogeneous enzyme immunoassay for aminoglycosides requires both the heparin polyanion and glucose-6-phosphate dehydrogenase bound to a cationic aminoglycoside. This interference can be reproduced with dextran sulfate (but not dextran), and does not occur with free enzyme (glucose-6-phosphate dehydrogenase) alone. Heparin interference with these two assays and at concentrations that may be present in intravenous infusions or in seriously underfilled blood-collection tubes is described. (JMT)

  5. MULTIPLEXED IMMUNOASSAYS FOR VIRAL PATHOGENS UTILIZING SURFACE-ENHANCED RAMAN SCATTERING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A sandwich immunoassay for the selective detection of viral pathogens has been developed using surface-enhanced Raman scattering (SERS) as the readout technology. The strengths of SERS-based detection include ultrahigh sensitivity and the possibility of multiplexing using multiple tags. The viabilit...

  6. Determination of deoxynivalenol in wheat bran and whole-wheat flour by fluorescence polarization immunoassay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A rapid and accurate fluorescence polarization (FP) immunoassay has been optimized for the determination of deoxynivalenol (DON) in bran and whole-wheat flour. A preliminary treatment with activated charcoal was used to eliminate the strong matrix effect due to highly colored interfering compounds p...

  7. Detection times of marijuana metabolites in urine by immunoassay and GC-MS.

    PubMed

    Huestis, M A; Mitchell, J M; Cone, E J

    1995-10-01

    Reports of prolonged drug excretion have provided the basis for the common assumption that cannabinoid metabolites may he detected in urine for a week or longer. The accuracy, sensitivity, and specificity of immunoassays for the detection of cannabinoids and metabolites are unique for a specific assay and may change overtime. it is important that individuals who select assays and those who interpret test results be aware of qualitative and quantitative changes that occur. In the present study, detection times of cannabinoids in urine were determined using cannabinoid immunoassays with 20-, 50-, and 100-ng/mL cutoffs and using gas chromatography-mass spectrometry (GC-MS). Six subjects each smoked a single marijuana cigarette (placebo, 1.75, or 3.55% delta9-tetrahydrocannabinol [THC]) each week while residing on the clinical ward of the Addiction Research Center. Each urine specimen was analyzed under blind conditions by immunoassay according to the manufacturer's instructions. The following cannabinoid reagents were evaluated: EMIT d.a.u. 100, EMIT d.a.u. 50, EMIT d.a.u. 20, EMIT II 100, EMIT II 50, Abuscreen OnLine, and Abuscreen RIA, DRI, and ADx. All urine specimens were also analyzed for 11-nor-9-carboxy-delta9-THC by GC-MS using a 15-ng/mL cutoff. Urinary cannabinoid detection times varied substantially across assays, subjects, doses, and cutoff concentrations. Detection times were shorter than previously assumed. Mean detection times increased from a maximum of 0.5 days after the low dose to 1.5 days after the high dose using the 100-ng/mL cutoff. Mean detection times were less than 1 day following the low dose and less than 2 days following high-dose exposure using the 50-ng/mL cutoff. Mean detection times ranged from 1 to 5 days after the low dose and from 3 to 6 days after the high dose using the 20-ng/mL cutoff immunoassay. GC-MS detection times were approximately twice as long as mean detection times using an immunoassay with a cutoff of 50 ng/mL. Differences in sensitivity and specificity between the available immunoassay products affected the efficiency of detection of marijuana use. These results indicate that recent reductions in cannabinoid cutoffs by military and federally mandated programs will increase detection times and improve sensitivity, as expected. However, monitoring acute marijuana usage with a commercial cannabinoid immunoassay that has a 50-ng/mL cutoff concentration provides only a narrow window of detection of 1-2 days. PMID:8926739

  8. Surface-Enhanced Raman Scattering (SERS) for Detection in Immunoassays: applications, fundamentals, and optimization

    SciTech Connect

    Jeremy Daniel Driskell

    2006-08-09

    Immunoassays have been utilized for the detection of biological analytes for several decades. Many formats and detection strategies have been explored, each having unique advantages and disadvantages. More recently, surface-enhanced Raman scattering (SERS) has been introduced as a readout method for immunoassays, and has shown great potential to meet many key analytical figures of merit. This technology is in its infancy and this dissertation explores the diversity of this method as well as the mechanism responsible for surface enhancement. Approaches to reduce assay times are also investigated. Implementing the knowledge gained from these studies will lead to a more sensitive immunoassay requiring less time than its predecessors. This dissertation is organized into six sections. The first section includes a literature review of the previous work that led to this dissertation. A general overview of the different approaches to immunoassays is given, outlining the strengths and weaknesses of each. Included is a detailed review of binding kinetics, which is central for decreasing assay times. Next, the theoretical underpinnings of SERS is reviewed at its current level of understanding. Past work has argued that surface plasmon resonance (SPR) of the enhancing substrate influences the SERS signal; therefore, the SPR of the extrinsic Raman labels (ERLs) utilized in our SERS-based immunoassay is discussed. Four original research chapters follow the Introduction, each presented as separate manuscripts. Chapter 2 modifies a SERS-based immunoassay previously developed in our group, extending it to the low-level detection of viral pathogens and demonstrating its versatility in terms of analyte type, Chapter 3 investigates the influence of ERL size, material composition, and separation distance between the ERLs and capture substrate on the SERS signal. This chapter links SPR with SERS enhancement factors and is consistent with many of the results from theoretical treatments of SPR and SERS. Chapter 4 introduces a novel method of reducing sample incubation time via capture substrate rotation. Moreover, this work led to a method of virus quantification without the use of standards. Chapter 5 extends the methodology developed in Chapter 4 to both the antigen and ERL labeling step to perform assays with improved analytical performance in less time than can be accomplished in diffusion controlled assays. This dissertation concludes with a general summary and speculates on the future of this exciting approach to carrying out immunoassays.

  9. Comparisons of Immunoassay and Mass Spectrometry Measurements of Serum Estradiol Levels and Their Influence on Clinical Association Studies in Men

    PubMed Central

    Nilsson, Maria E.; Tivesten, ?sa; Ryberg, Henrik; Mellström, Dan; Karlsson, Magnus K.; Ljunggren, Östen; Labrie, Fernand; Orwoll, Eric S.; Lee, David M.; Pye, Stephen R.; O'Neill, Terence W.; Finn, Joseph D.; Adams, Judith E.; Ward, Kate A.; Boonen, Steven; Bartfai, Gyorgy; Casanueva, Felipe F.; Forti, Gianni; Giwercman, Aleksander; Han, Thang S.; Huhtaniemi, Ilpo T.; Kula, Krzysztof; Lean, Michael E. J.; Pendleton, Neil; Punab, Margus; Vanderschueren, Dirk; Wu, Frederick C. W.; Vandenput, Liesbeth

    2013-01-01

    Context: Immunoassay-based techniques, routinely used to measure serum estradiol (E2), are known to have reduced specificity, especially at lower concentrations, when compared with the gold standard technique of mass spectrometry (MS). Different measurement techniques may be responsible for the conflicting results of associations between serum E2 and clinical phenotypes in men. Objective: Our objective was to compare immunoassay and MS measurements of E2 levels in men and evaluate associations with clinical phenotypes. Design and Setting: Middle-aged and older male subjects participating in the population-based Osteoporotic Fractures in Men (MrOS) Sweden study (n = 2599), MrOS US (n = 688), and the European Male Aging Study (n = 2908) were included. Main Outcome Measures: Immunoassay and MS measurements of serum E2 were compared and related to bone mineral density (BMD; measured by dual energy x-ray absorptiometry) and ankle-brachial index. Results: Within each cohort, serum E2 levels obtained by immunoassay and MS correlated moderately (Spearman rank correlation coefficient rS 0.53–0.76). Serum C-reactive protein (CRP) levels associated significantly (albeit to a low extent, rS = 0.29) with immunoassay E2 but not with MS E2 levels. Similar associations of immunoassay E2 and MS E2 were seen with lumbar spine and total hip BMD, independent of serum CRP. However, immunoassay E2, but not MS E2, associated inversely with ankle-brachial index, and this correlation was lost after adjustment for CRP. Conclusions: Our findings suggest interference in the immunoassay E2 analyses, possibly by CRP or a CRP-associated factor. Although associations with BMD remain unaffected, this might imply for a reevaluation of previous association studies between immunoassay E2 levels and inflammation-related outcomes. PMID:23633197

  10. Investigation of Antigen-Antibody Interactions of Sulfonamides with a Monoclonal Antibody in a Fluorescence Polarization Immunoassay Using 3D-QSAR Models

    PubMed Central

    Wang, Zhanhui; Kai, Zhenpeng; Beier, Ross C.; Shen, Jianzhong; Yang, Xinling

    2012-01-01

    A three-dimensional quantitative structure-activity relationship (3D-QSAR) model of sulfonamide analogs binding a monoclonal antibody (MAbSMR) produced against sulfamerazine was carried out by Distance Comparison (DISCOtech), comparative molecular field analysis (CoMFA), and comparative molecular similarity indices analysis (CoMSIA). The affinities of the MAbSMR, expressed as Log10IC50, for 17 sulfonamide analogs were determined by competitive fluorescence polarization immunoassay (FPIA). The results demonstrated that the proposed pharmacophore model containing two hydrogen-bond acceptors, two hydrogen-bond donors and two hydrophobic centers characterized the structural features of the sulfonamides necessary for MAbSMR binding. Removal of two outliers from the initial set of 17 sulfonamide analogs improved the predictability of the models. The 3D-QSAR models of 15 sulfonamides based on CoMFA and CoMSIA resulted in q2 cv values of 0.600 and 0.523, and r2 values of 0.995 and 0.994, respectively, which indicates that both methods have significant predictive capability. Connolly surface analysis, which mainly focused on steric force fields, was performed to complement the results from CoMFA and CoMSIA. This novel study combining FPIA with pharmacophore modeling demonstrates that multidisciplinary research is useful for investigating antigen-antibody interactions and also may provide information required for the design of new haptens. PMID:22754368

  11. Thermoelectric Performance of Donor-Acceptor-Donor Conjugated Polymers Based on Benzothiadiazole Derivatives

    NASA Astrophysics Data System (ADS)

    Ming, Shouli; Zhen, Shijie; Lin, Kaiwen; Zhao, Li; Xu, Jingkun; Lu, Baoyang; Wang, Liangying; Xiong, Jinhua; Zhu, Zhengzhou

    2014-11-01

    Donor-acceptor-donor conjugated polymers are superior to other thermoelectric organic materials because it is much easier to modify their structure to reduce the bandgap between the conduction and valence bands, which is desirable for thermoelectric materials with high Seebeck coefficients. Despite this, studies of the thermoelectric performance of donor-acceptor-donor conjugated polymers are rare. In this study, four low-bandgap donor-acceptor-donor conjugated polymers, poly(4,7-bis(2,3-dihydrothieno[3,4-b][1,4] dioxin-5-yl)benzo[c][1,2,5]thiadiazole) (PEBTE), poly(4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)benzo[c][1,2,5]selenadiazole) (PEBSeE), poly (4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-[1,2,5]thiadiazolo [3,4-c] pyridine) (PEPTE), and poly(4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-[1,2,5]selenadiazolo[3,4-c]pyridine) (PEPSeE), were deposited by electrochemical polymerization of 4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)benzo[c][1,2,5]thiadiazole (EBTE), 4,7-bis(2,3-dihydro-thieno[3,4-b][1,4] dioxin-5-yl)benzo[c][1,2,5]selenadiazole (EBSeE), 4,7-bis(2,3-dihydrothieno [3,4-b][1,4]dioxin-5-yl)-[1,2,5]thiadiazolo[3,4-c] pyridine (EPTE) and 4,7-bis (2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-[1,2,5] selenadiazolo[3,4-c]pyridine (EPSeE), respectively and their thermoelectric performance was investi- gated. Compared with polyselenophenes, PEBTE and PEBSeE in pressed pellets had higher electrical conductivity (10-1-101 S cm-1) but lower Seebeck coefficient (14.0 ?V K-1) at room temperature. Future work may focus on treatment of these donor-acceptor-donor polymers to improve their electrical conductivity and Seebeck coefficient, and further investigation of their thermoelectric performance.

  12. [ABO polymorphism in blood donors in Morocco].

    PubMed

    Habti, N; Nourichafi, N; Benchemsi, N

    2004-04-01

    Blood grouping were improved since the advent of monoclonal antibodies and the automation of the tests. No comparative study has been done before in Morocco concerning ABO regional genetic frequencies. Hence, the aim of this work is to actualize and to precise them. The ABO blood grouping has been carried out on 344 954 blood donors by micro method in several regional blood transfusion centers. Genetic frequencies were calculated according to the Bernstein's method. The national mean values are A: 0.2141, B: 0.105, O: 0.6777. The regional frequencies show gradients between the north and the south of Morocco. PMID:15120106

  13. Ethical aspects of donor consent in transplantation

    PubMed Central

    Mahoney, John

    1975-01-01

    Two recent events have caused renewed anxiety concerning the ethics of donor transplantation. The first is the report of the British Transplantation Society and the second is the Bill introduced by Mr Tam Dalyell MP (see page 61 of this issue) in which he seeks to establish by law that unless an individual in his life time has expressly contracted out his organs may after death be used for transplantation. Dr Mahoney in this paper therefore examines from the point of view of ethics some of the personal and social aspects of both proposals. PMID:1177269

  14. Evaluation of potential liver donors: Limits imposed by donor variables in liver transplantation

    Microsoft Academic Search

    Ramón Rull; Oscar Vidal; Dulce Momblan; Francisco Xavier González; Miguel Angel López-Boado; Jose Fuster; Luis Grande; Miguel Bruguera; Katiana Cabrer; Juan Carlos Garc??a-Valdecasas

    2003-01-01

    The aim of this study was to evaluate the predictive value of different donor and recipient parameters that have been recognised previously as proven and to suggest prognostic factors for immediate liver function and final outcome after liver transplantation. We evaluated a total of 228 liver grafts transplanted in the last 3 years in our institution. Parameters were recorded for

  15. Approach to the Pretransplant Evaluation of the Living Kidney Donor

    PubMed Central

    Sachdeva, Mala; Bhaskaran, Madhu; Molmenti, Ernesto P.; Dalton, Donna; Mattana, Joseph

    2011-01-01

    Evaluation of the potential kidney donor is a complex activity that differs substantially from other types of preoperative assessments. The well being of the donor, who derives no medical benefit from this surgery, must be assured in both the short term and long term, and the potential adverse consequences to the recipient must be determined as well. The criteria that must be met for a person to donate a kidney are rigorous and include medical, social, psychosocial, ethical, and legal issues. Donor evaluation can be divided into assessments to protect the health and safety of the donor and assessments to protect the health and safety of the recipient. This article provides an approach to evaluating a donor, focusing on the complex issues that an evaluator is faced with. A careful assessment of risks and benefits to both the donor and recipient can lead to favorable outcomes. PMID:22254127

  16. A brown dwarf mass donor in an accreting binary.

    PubMed

    Littlefair, S P; Dhillon, V S; Marsh, T R; Gänsicke, Boris T; Southworth, John; Watson, C A

    2006-12-01

    A long-standing and unverified prediction of binary star evolution theory is the existence of a population of white dwarfs accreting from substellar donor stars. Such systems ought to be common, but the difficulty of finding them, combined with the challenge of detecting the donor against the light from accretion, means that no donor star to date has a measured mass below the hydrogen burning limit. We applied a technique that allowed us to reliably measure the mass of the unseen donor star in eclipsing systems. We were able to identify a brown dwarf donor star, with a mass of 0.052 +/- 0.002 solar mass. The relatively high mass of the donor star for its orbital period suggests that current evolutionary models may underestimate the radii of brown dwarfs. PMID:17158322

  17. Donor-gifted allograft urolithiasis: early percutaneous management

    Microsoft Academic Search

    Hsueh-Fu Lu; Bijan Shekarriz; Marshall L Stoller

    2002-01-01

    Objectives. To describe our successful early management of donor-gifted nephrolithiasis by percutaneous nephrolithotomy. Donor-gifted nephrolithiasis is a rare and frustrating complication of renal transplantation. In the past, initial conservative management with relief of obstruction and shock wave lithotripsy has been recommended.Methods. We treated 3 cases of donor-gifted cadaveric kidney transplant stones by a percutaneous approach 1 to 2 months postoperatively.

  18. Evaluation of a fluorescent polarization immunoassay for whole blood everolimus determination using samples from renal transplant recipients

    Microsoft Academic Search

    Paul Salm; Christopher Warnholtz; Jared Boyd; Lili Arabshahi; Peter Marbach; Paul J. Taylor

    2006-01-01

    Objectives:This study compared the performance of a fluorescent polarization immunoassay (FPIA) against HPLC-tandem mass spectrometry (HPLC-MS) for the measurement of everolimus in renal transplant recipients.

  19. In vitro conditions modify immunoassayability of bovine pituitary prolactin and growth hormone: insights into their secretory granule storage forms

    SciTech Connect

    Lorenson, M.Y.

    1985-04-01

    The amount of immunoassayable intracellular bovine (b) PRL and GH varies depending on treatment conditions. The present studies were designed to characterize the mechanisms involved and to compare immunoassayability of both hormones under similar conditions. Pituitary homogenate and secretory granule hormones displayed both time- and temperature-dependent increases when incubated at pH 10.5 with reduced glutathione. Changes in immunoassayability seem to reflect conversion from poorly immunoactive tissue hormone oligomers to monomeric hormone. The data indicate that oligomeric bPRL is stabilized primarily by intermolecular disulfide bonds, although it is also susceptible to urea, SDS, and EDTA; granule thiols may also influence the conversion to monomer. The storage form of bGH appears to be stabilized differently. Maneuvers demonstrated in these studies to influence immunoassayability correlate very well with their previously established effects on hormone release and secretion, strengthening the likelihood that a functional link exists between assayability and secretion.

  20. Isolation of Alpaca Anti-Idiotypic Heavy-Chain Single-Domain Antibody for the Aflatoxin Immunoassay

    E-print Network

    Hammock, Bruce D.

    Isolation of Alpaca Anti-Idiotypic Heavy-Chain Single-Domain Antibody for the Aflatoxin Immunoassay an antibody phage library from the mRNA of an alpaca immunized with an antiaflatoxin monoclonal antibody (m

  1. DEMONSTRATION BULLETIN: PCP IMMUNOASSAY TECHNOLOGIES - PENTA RISC BY ENSYS INC., PENTA RAPID BY OHMICRON CORP., ENVIROGARD BY MILLIPORE

    EPA Science Inventory

    The objectives of this demonstration were to test these field screening technologies for accuracy and precision in detecting Pentachlorophenol (PCP) levels in soil and water by comparing their results with those of a confirmatory laboratory. The three immunoassay technologies ...

  2. Performance of a Time-Resolved Fluorescence Immunoassay for Measuring Varicella-Zoster Virus Immunoglobulin G Levels in Adults and Comparison with Commercial Enzyme Immunoassays and Merck Glycoprotein Enzyme Immunoassay

    PubMed Central

    Maple, P. A. C.; Gray, J.; Breuer, J.; Kafatos, G.; Parker, S.; Brown, D.

    2006-01-01

    Highly sensitive and specific, quantitative assays are needed to detect varicella-zoster virus (VZV) immunoglobulin G in human sera, particularly for determining immune status and response following vaccination. A time-resolved fluorescence immunoassay (TRFIA) has been developed, and its performance was compared to that of two commercial enzyme immunoassays (EIAs) and Merck glycoprotein EIA (gpEIA). The TRFIA had equivalent sensitivity (97.8%) and high specificity (93.5%) in relation to gpEIA. A commercial (Behring) EIA compared favorably with TRFIA in terms of sensitivity (98.4%) but had lower specificity (80.7%). Another commercial EIA (Diamedix) had high specificity (97.1%) but low sensitivity (76.4%) compared to TRFIA if equivocal test results were treated as negative for VZV antibody. A novel feature of the TRFIA was that the cutoff was generated using population mixture modeling and was expressed in mIU/ml, as the assay was calibrated using the British standard VZV antibody. PMID:16467328

  3. Evaluation of immunoassays for the measurement of erythropoietin (EPO) as an indirect biomarker of recombinant human EPO misuse in sport

    Microsoft Academic Search

    Rosario Abellan; Rosa Ventura; Simona Pichini; Angel Francisco Remacha; Jose Antonio Pascual; Roberta Pacifici; Rita Di Giovannandrea; Piergiorgio Zuccaro; Jordi Segura

    2004-01-01

    The measurement of serum erythropoietin (EPO) has been proposed as one of the indirect biomarkers for the detection of recombinant human EPO misuse in sport. An extended inter-laboratory validation of two commercial immunoassays for EPO measurement is described. A chemiluminescent immunoassay kit (CHEM) and an enzyme-linked immunosorbent assay kit (ELISA) were evaluated.The CHEM assay showed intra-laboratory precision better than 6%

  4. Preparation of pH-sensitive polymer by thermal initiation polymerization and its application in fluorescence immunoassay

    Microsoft Academic Search

    Peng Lin; Jian-Jun Feng; Hong Zheng; Huang-Hao Yang; Jin-Gou Xu

    2005-01-01

    A fluorescence immunoassay for human IgG (Ag) was developed using a pH-sensitive polymer prepared by thermal initiation or redox initiation polymerization as a carrier. In the competitive immunoassay, appropriate quantity of Ag was immobilized on the polymer and the standard Ag (or sample) solution, and a constant amount of fluorescein isothiocyanate labeled goat anti-human IgG antibody (Ab-FITC) was added. Immobilized

  5. The donor-conceived child's "Right to Personal Identity": the public debate on donor anonymity in the United Kingdom.

    PubMed

    Turkmendag, Ilke

    2012-01-01

    On 1 April 2005, with the implementation of the Human Fertilisation and Embryology Authority (Disclosure of Donor Information) Regulations 2004, United Kingdom law was changed to allow children born through gamete donation to access details identifying the donor. Drawing on trends in adoption law, the decision to abolish donor anonymity was strongly influenced by a discourse that asserted the ‘child's right to personal identity’. Through examination of the donor anonymity debate in the public realm, while adopting a social constructionist approach, this article discusses how donor anonymity has been defined as a social problem that requires a regulative response. It focuses on the child's ‘right to personal identity’ claims, and discusses the genetic essentialism behind these claims. By basing its assumptions on an adoption analogy, United Kingdom law ascribes a social meaning to the genetic relatedness between gamete donors and the offspring. PMID:22530247

  6. Specific inhibitory effects of the NO donor MAHMA/NONOate on human platelets.

    PubMed

    Kobsar, Anna; Simonis, Sandra; Klinker, Erdwine; Koessler, Angela; Kuhn, Sabine; Boeck, Markus; Koessler, Juergen

    2014-07-15

    Nitric oxide (NO) is a physiological inhibitor of platelet function and has vaso-dilating effects. Therefore, synthesized NO releasing agents are used e.g. in cardiovascular medicine. The aim of this study was to characterise specific effects of the short living agent MAHMA/NONOate, a NO donor of the diazeniumdiolate class, on human platelets. Whole blood was obtained from healthy volunteers. In washed human platelets, the MAHMA/NONOate induced phosphorylation of the vasodilator-stimulated phosphoprotein (VASP) and cyclic nucleotide production were studied by Western Blot and by enzyme immunoassay kits. Agonist induced aggregation was measured in platelet rich plasma. Paired Student?s t-test was used for statistical analysis. MAHMA/NONOate significantly stimulated platelet VASP phosphorylation in a concentration dependent manner and increased intracellular cGMP, but not cAMP levels, transiently. ODQ, a specific inhibitor of the soluble guanylyl cyclase, completely prevented VASP phosphorylation induced by low MAHMA/NONOate concentrations (5nM-15nM). The effects of higher concentrations (30-200nM) were only partially inhibited by ODQ. MAHMA/NONOate reduced platelet aggregation induced by low doses of agonists (2µM ADP, 0.5µg/mL collagen, 5µM TRAP-6) in a concentration dependent manner. MAHMA/NONOate leads to a rapid and transient activation of platelet inhibitory systems, accompanied by decreased platelet aggregation induced by low dose agonists. At low MAHMA/NONOate concentrations, the effects are cGMP dependent and at higher concentrations additionally cGMP independent. The substance could be of interest for clinical situations requiring transient and subtotal inhibition of platelet function. PMID:24780647

  7. [Laparoscopic living donor nephrectomy of kidneys with multiple renal vessels].

    PubMed

    Giessing, M; Deger, S; Ebeling, V; Schönberger, B; Roigas, J; Kroencke, T J; Türk, I

    2003-02-01

    Due to the increasing waiting time for transplantation of a cadaveric kidney, living donor kidney transplantation is an increasingly oncoming issue. Laparoscopic donor nephrectomies (LDN) have been performed since 1995 and presently more than 100 transplant centers offer this minimally invasive surgical approach. The advantages for the donor of less pain, shorter hospital stay, earlier return to work, better cosmetic results in combination with an organ function equal to open donor nephrectomy are the reasons for an enormous increase in LDN. Since up to 30% of the donor kidneys have multiple vessels for blood supply, an increase of these organs for LDN can be expected. We performed a retrospective study of LDN at our center and compared donors with multiple vs single vessel supply. From February 1999 to September 2002, 63 LDN were performed at the department of Urology, Charité University Hospital, Berlin. A comparison between 18 donor kidneys with multiple vessel supply and 45 donor organs with single vessels showed no difference for the time of laparoscopic explantation (207 vs 201 min, p=0.4) or the warm (166 vs 148 s, p=0.2) and cold ischemic times (117 vs 103 min, p=0.66). As could be expected, the mixed ischemic time, i.e., the time for anastomosis of the kidney with the recipient's vessels, showed a significant difference (53 vs 46 min, p=0.02). Intra- and postoperative complication rates for donors and recipients were not different in both groups. Laparoscopic donor nephrectomy for kidneys with multiple vessels is feasible and safe for donor and recipient. PMID:12607091

  8. A microsphere-based immunoassay for rapid and sensitive detection of bovine viral diarrhoea virus antibodies.

    PubMed

    Xia, Hongyan; Liu, Lihong; Nordengrahn, Ann; Kiss, István; Merza, Malik; Eriksson, Ronnie; Blomberg, Jonas; Belák, Sándor

    2010-09-01

    This study describes a novel blocking microsphere-based immunoassay for highly sensitive and specific detection of antibodies against bovine viral diarrhoea virus (BVDV). The intra- and inter-assay variability are 4.9% and less than 7%, respectively, and variability of bead conjugations is less than 6.6%. The diagnostic performance of the assay was evaluated by testing a total of 509 serum samples. Based on a negative/positive cut-off value of 30.3%, the assay has a sensitivity of 99.4% and a specificity of 98.3% relative to ELISA. The new microsphere immunoassay provides an alternative to conventional ELISA systems and can be used for high-throughput screening in the BVD control programmes. PMID:20403384

  9. A competitive chemiluminescence enzyme immunoassay for rapid and sensitive determination of enrofloxacin

    NASA Astrophysics Data System (ADS)

    Yu, Fei; Wu, Yongjun; Yu, Songcheng; Zhang, Huili; Zhang, Hongquan; Qu, Lingbo; Harrington, Peter de B.

    With alkaline phosphatase (ALP)-adamantane (AMPPD) system as the chemiluminescence (CL) detection system, a highly sensitive, specific and simple competitive chemiluminescence enzyme immunoassay (CLEIA) was developed for the measurement of enrofloxacin (ENR). The physicochemical parameters, such as the chemiluminescent assay mediums, the dilution buffer of ENR-McAb, the volume of dilution buffer, the monoclonal antibody concentration, the incubation time, and other relevant variables of the immunoassay have been optimized. Under the optimal conditions, the detection linear range of 350-1000 pg/mL and the detection limit of 0.24 ng/mL were provided by the proposed method. The relative standard deviations were less than 15% for both intra and inter-assay precision. This method has been successfully applied to determine ENR in spiked samples with the recovery of 103%-96%. It showed that CLEIA was a good potential method in the analysis of residues of veterinary drugs after treatment of related diseases.

  10. Liver cancer immunoassay with magnetic nanoparticles and MgO-based magnetic tunnel junction sensors

    NASA Astrophysics Data System (ADS)

    Lei, Z. Q.; Li, L.; Li, G. J.; Leung, C. W.; Shi, J.; Wong, C. M.; Lo, K. C.; Chan, W. K.; Mak, C. S. K.; Chan, S. B.; Chan, N. M. M.; Leung, C. H.; Lai, P. T.; Pong, P. W. T.

    2012-04-01

    We have demonstrated the detection of alpha-fetoprotein (AFP) labeled with magnetic nanoparticles (MNPs) using MgO-based magnetic tunnel junction (MTJ) sensors. AFP is an important hepatic tumor biomarker and the detection of AFP has significant applications for clinical diagnostics and immunoassay for early-stage liver cancer indications. In this work, MgO-based MTJ sensors and 20-nm iron-oxide magnetic nanoparticles (MNPs) were used for detecting AFP antigens by a sandwich-assay configuration. The MTJ sensors with a sensing area of 4 × 2 ?m2 possess tunneling magnetoresistance (TMR) of 122% and sensitivity of 0.95%/Oe at room temperature. The target AFP antigens of three concentrations were successfully detected, and the experimental data indicate that the resistance variations of the MTJ sensor increased with the AFP concentration ratios proportionally. These results demonstrate that MgO-based MTJ sensors together with MNPs are a promising biosensing platform for liver cancer immunoassay.

  11. Two dimensional barcode-inspired automatic analysis for arrayed microfluidic immunoassays

    PubMed Central

    Zhang, Yi; Qiao, Lingbo; Ren, Yunke; Wang, Xuwei; Gao, Ming; Tang, Yunfang; Jeff Xi, Jianzhong; Fu, Tzung-May; Jiang, Xingyu

    2013-01-01

    The usability of many high-throughput lab-on-a-chip devices in point-of-care applications is currently limited by the manual data acquisition and analysis process, which are labor intensive and time consuming. Based on our original design in the biochemical reactions, we proposed here a universal approach to perform automatic, fast, and robust analysis for high-throughput array-based microfluidic immunoassays. Inspired by two-dimensional (2D) barcodes, we incorporated asymmetric function patterns into a microfluidic array. These function patterns provide quantitative information on the characteristic dimensions of the microfluidic array, as well as mark its orientation and origin of coordinates. We used a computer program to perform automatic analysis for a high-throughput antigen/antibody interaction experiment in 10 s, which was more than 500 times faster than conventional manual processing. Our method is broadly applicable to many other microchannel-based immunoassays. PMID:24404030

  12. Sugar additives improve signal fidelity for implementing two-phase resorufin-based enzyme immunoassays.

    PubMed

    Sandoz, Patrick A; Chung, Aram J; Weaver, Westbrook M; Di Carlo, Dino

    2014-06-17

    Enzymatic signal amplification based on fluorogenic substrates is commonly used for immunoassays; however, when transitioning these assays to a digital format in water-in-mineral oil emulsions, such amplification methods have been limited by the leakage of small reporting fluorescent probes. In the present study, we used a microfluidic system to study leakage from aqueous droplets in a controlled manner and confirmed that the leakage of fluorescent resorufin derivatives is mostly due to the presence of the lipophilic surfactant Span80, which is commonly used to preserve emulsion stability. This leakage can be overcome by the addition of specific sugars that most strongly interfered with the surfactants ability to form micelles in water. The application of the microfluidic system to the quantitative analysis of droplets and the implementation of the described sugar additives would allow for alternatives to fluorinated surfactant-based platforms and improve the signal fidelity in enzyme immunoassays implemented through multiphase microfluidics. PMID:24870310

  13. Immunoassays for trifloxystrobin analysis. Part II. Assay development and application to residue determination in food.

    PubMed

    Mercader, Josep V; López-Moreno, Rosario; Esteve-Turrillas, Francesc A; Abad-Somovilla, Antonio; Abad-Fuentes, Antonio

    2014-11-01

    Immunochemical assays constitute complementary analytical methods for small organic molecule determination. We herein describe the characterisation and optimisation of two competitive enzyme-linked immunosorbent assays in different formats using monoclonal antibodies to the Quinone outside inhibitor (QoI) fungicide trifloxystrobin. Antibody selectivity was evaluated using a variety of agrochemicals and the main trifloxystrobin metabolite. Acceptable tolerance of the immunoassay to methanol, ethanol, and acetonitrile was observed in all cases, whereas a dissimilar influence of buffer pH and ionic strength was found. Moreover, the influence of Tween 20 over the analytical parameters was studied. The limits of detection of the optimised assays were below 0.1 ?g L(-1). Excellent recoveries, even at 10 ?g kg(-1), were obtained when strawberry, tomato, and cucumber samples spiked with trifloxystrobin were analysed. Finally, statistical agreement was found between immunoassay and reference chromatographic results using blind-spiked and in-field treated samples. PMID:24874355

  14. IFSA: a microfluidic chip-platform for frit-based immunoassay protocols

    NASA Astrophysics Data System (ADS)

    Hlawatsch, Nadine; Bangert, Michael; Miethe, Peter; Becker, Holger; Gärtner, Claudia

    2013-03-01

    Point-of-care diagnostics (POC) is one of the key application fields for lab-on-a-chip devices. While in recent years much of the work has concentrated on integrating complex molecular diagnostic assays onto a microfluidic device, there is a need to also put comparatively simple immunoassay-type protocols on a microfluidic platform. In this paper, we present the development of a microfluidic cartridge using an immunofiltration approach. In this method, the sandwich immunoassay takes place in a porous frit on which the antibodies have immobilized. The device is designed to be able to handle three samples in parallel and up to four analytical targets per sample. In order to meet the critical cost targets for the diagnostic market, the microfluidic chip has been designed and manufactured using high-volume manufacturing technologies in mind. Validation experiments show comparable sensitivities in comparison with conventional immunofiltration kits.

  15. Serologic test-systems development: immunoassays for antibiotics. Progress report, May 16, 1980-September 30, 1981

    SciTech Connect

    Brake, R.; Hollstein, U.; Hindman, K.

    1983-04-01

    Progress on development of immunoassays for the antibiotics gentamicin, tetracycline, and tylosin is discussed. The development of the gentamicin assay was completed and the assay was transferred to the Beltsville Laboratories of the US Department of Agriculture (USDA) Food Safety and Quality Service (FSQS). The sensitivity (1 ppB) is 50-fold greater than we have previously reported, and is satisfactory for the current needs. At year's end, work was still in progress on both the tetracycline and tylosin assays. Tetracycline presents a more difficult problem of chemistry than we had anticipated. Immunoassay reagents synthesized by diazonium coupling were only weakly immunoreactive; analysis suggests that this coupling procedure damages the tetracycline structure. Several tetracycline derivatives that offer promising alternative coupling procedures were synthesized. Tylosin was successfully coupled to peroxidase. With this conjugate and antiserum, obtained from R. Mageau of the USDA, some immune-specific binding was demonstrated. Several problems with the tylosin assay remain to be resolved.

  16. Liposome flow injection immunoassay: implications for sensitivity, dynamic range, and antibody regeneration.

    PubMed

    Locascio-Brown, L; Plant, A L; Horváth, V; Durst, R A

    1990-12-01

    We have developed a liposome-based flow injection immunoassay (FIIA) system for quantitation of a clinical analyte, theophylline. With very minor changes in assay format, this procedure can also be used for the quantitation of anti-theophylline. Automated sequential analyses were performed at room temperature with picomole sensitivity and a day-to-day coefficient of variation of less than 5% for aqueous solutions. The system components include liposomes that contain fluorophores in their aqueous centers and an immobilized-antibody reactor column. The immunoreactor was regenerated hundreds of times over 3 months of continuous use with no measurable loss of antibody activity. The two assay formats studied produced distinct dynamic ranges for their respective analytes. The special advantages of using flow injection analysis for immunoassays and of using liposomes in FIIA are discussed. PMID:2288414

  17. Recent developments in nitric oxide donor drugs

    PubMed Central

    Miller, M R; Megson, I L

    2007-01-01

    During the 1980s, the free radical, nitric oxide (NO), was discovered to be a crucial signalling molecule, with wide-ranging functions in the cardiovascular, nervous and immune systems. Aside from providing a credible explanation for the actions of organic nitrates and sodium nitroprusside that have long been used in the treatment of angina and hypertensive crises respectively, the discovery generated great hopes for new NO-based treatments for a wide variety of ailments. Decades later, however, we are still awaiting novel licensed agents in this arena, despite an enormous research effort to this end. This review explores some of the most promising recent advances in NO donor drug development and addresses the challenges associated with NO as a therapeutic agent. PMID:17401442

  18. The degree of safety of family replacement donors versus voluntary non-remunerated donors in an Egyptian population: a comparative study

    PubMed Central

    Abdel Messih, Ibrahim Y.; Ismail, Mona A.; Saad, Abeer A.; Azer, Mary R.

    2014-01-01

    Background Screening donated blood for transfusion-transmissible infections is considered an important strategy for maximising the safety of blood transfusions. Materials and methods A total of 17,118 donors, classified into two groups - family replacement donors and voluntary non-remunerated donors - were investigated for hepatitis B virus (HBV) surface antigen and antibodies against hepatitis C virus (HCV), human immunodeficiency virus (HIV) and Treponema pallidum. In addition cytomegalovirus (CMV) antibodies were searched for in 160 donors (80 from each group). All the laboratory tests were done using enzyme-linked immunosorbent assays. Results Of the total cohort of donors, 87.7% were family donors and 12.3% were voluntary non-remunerated donors. There was a highly significant difference in age and gender between the two types of donors with voluntary donors being much younger and including a much higher proportion of male donors than female donors. The prevalences of HBV, HCV and CMV IgG were much higher in family donors than in voluntary donors, with the differences being highly statistically significant. There was also a significantly higher prevalence of syphilis among family replacement donors. As regards HIV and CMV IgM, significant differences were not detected between the two groups. Discussion The results of our study clearly showed that the prevalence of transfusion-transmissible infections is much higher among family replacement donors than among voluntary donors, and that voluntary donors are the best way of achieving safer blood. PMID:23245714

  19. USING A COMMERCIALLY AVAILABLE ENZYME IMMUNOASSAY TO QUANTIFY TESTOSTERONE IN AVIAN PLASMA

    Microsoft Academic Search

    BRIAN E. WASHBURN; JOSHUA J. MILLSPAUGH; DANA L. MORRIS; JOHN H. SCHULZ; JOHN FAABORG

    2007-01-01

    Using a commercially available testos- terone enzyme immunoassay (EIA), we developed and validated an assay procedure for determining testosterone levels in small-volume (20 mL) avian plasma samples. We evaluated this EIA's utility by measuring plasma testosterone levels in Mourning Doves (Zenaida macroura), White-eyed Vireos (Vireo griseus), Red-eyed Vireos (Vireo olivaceus), and Indigo Buntings (Passerina cyanea). Standard bio- chemical validations (e.g.,

  20. Tube-Immunoassay for Rapid Detection of Carbaryl Residues in Agricultural Products

    Microsoft Academic Search

    SHUO WANG; CHUNDI YU; YAN ZHANG; JUNPING WANG; ZHENJUAN DUAN; JUANKUN ZHANG

    2006-01-01

    An antibody-based rapid, quantitative, and qualitative tube enzyme-linked immunosorbent assay (tube-ELISA) was developed and used to determine carbaryl (1-naphthyl methylcarbamate) residues in agricultural products (apple, Chinese cabbage, rice, and barley). The tube-ELISA is a competitive immunoassay in which the antibody is coated in the polystyrene tube, with a dynamic range between 0.7 and 46.3 ?g kg. Carbaryl was extracted from

  1. Magnetic luminescent nanoparticles as internal calibration for an immunoassay for ricin

    NASA Astrophysics Data System (ADS)

    Dosev, Dosi; Nichkova, Mikaela; Ma, Zhi-Ya; Gee, Shirley J.; Hammock, Bruce D.; Kennedy, Ian M.

    2008-02-01

    Fluorescence techniques rely on measurement of relative fluorescence units and require calibration to obtain reliable and comparable quantitative data. Fluorescent immunoassays are a very sensitive and convenient method of choice for rapid detection of biotoxins, such as ricin. Here we present the application of magnetic luminescent nanoparticles (MLNPs) with a magnetic core of Fe 3O 4 and a fluorescent shell of Eu:Gd IIO 3 as carriers for a nanobead-immunoassay for the detection of ricin with internal calibration. A sandwich immunoassay for ricin was performed on the surface of the MLNPs. The particles were functionalized with capture polyclonal antibodies. Anti-ricin antibodies labeled with Alexa Fluor dye were used as the detecting antibodies. After magnetic extraction, the amount of ricin bound to the particle surface was quantified and related to the fluorescence signal of the nanoparticles. In this new platform, the MLNPs have three main functions: (1) a probe for the specific extraction of the target analyte from the sample; (2) a carrier in the quantitative immunoassay with magnetic separation; and (3) an internal standard in the fluorescence measurement of the dye reporter. The MLNPs serve as an internal control for the total analysis including extraction and assay performance. This approach eliminates the experimental error inherent in particle extraction and measurement of absolute organic dye fluorescence intensities. All fluorescent measurements were performed in a microplate reader. The standard curve for ricin had a dynamic range from 20 ng/ml to 100 ?g/ml with a detection limit of 5 ng/ml. The configuration that has been developed can be easily adapted to a high throughput miniaturized system.

  2. Comparison of fluorescent polarization immunoassay (FPIA) versus HPLC to measure everolimus blood concentrations in clinical transplantation

    Microsoft Academic Search

    GholamAli Khoschsorur; Franz Fruehwirth; Sieglinde Zelzer; Mariana Stettin; Gabriele Halwachs-Baumann

    2007-01-01

    Clinical management of transplant patients depends on therapeutic drug monitoring (TDM) and regulation of immunosuppressive therapy. TDM of whole-blood concentrations is mandatory for everolimus (ERL) dosage individualisation. We compared the new semi-automated immunoassay (Innofluor® Certican® Assay System, Seradyn Inc) using FPIA technology on Abbott TDxFLx® analyzers with established HPLC-UV as reference method.A total of 165 samples were analyzed from 52

  3. Determination of Alachlor in food products by a fluorescence polarization immunoassay

    Microsoft Academic Search

    Yu. V. Nartova; T. N. Ermolaeva; M. R. Fleisher; R. Abuknesha; S. A. Eremin

    2008-01-01

    A procedure for the determination of Alachlor in liquid media using a fluorescence polarization immunoassay (FPIA) was developed.\\u000a The effects of the structure and purification degree of a tracer (analyte with a fluorescent label) on the analytical signals,\\u000a sensitivity, and selectivity in the determination of Alachlor were studied. The tracer-antibody binding constants (K\\u000a T) and antigen-antibody binding constants (affinity constants

  4. A clinical trial for therapeutic drug monitoring using microchip-based fluorescence polarization immunoassay

    Microsoft Academic Search

    Tomoya Tachi; Tetsunari Hase; Yukihiro Okamoto; Noritada Kaji; Takeshi Arima; Hiroyuki Matsumoto; Masashi Kondo; Manabu Tokeshi; Yoshinori Hasegawa; Yoshinobu Baba

    Microchip analysis is a promising method for therapeutic drug monitoring. This led us to evaluate a microchip-based fluorescence\\u000a polarization immunoassay (FPIA) system for point-of-care testing on patients being treated with theophylline. The sera were\\u000a collected from 20 patients being treated with theophylline. Fluorescence polarization was measured on the microchip and theophylline\\u000a concentrations in serum were obtained. Regression analysis of the

  5. Determination of netilmicin in serum by thin-layer densitometry and fluorescence polarization immunoassay

    Microsoft Academic Search

    Franz Rudolf Kunz; Hellmut Jork; Hans Erich Keller

    1993-01-01

    A newly developed thin-layer chromatographic method (TLC) for the quantitative determination of netilmicin in serum is described and compared with fluorescence polarization immunoassay (FPIA). The TLC procedure involves solid-phase extraction of the aminoglycoside from serum and chromatography on reversed-phase thin layer. Post-chromatographic derivatization is carried out using 2,2-diphenyl-1-oxa-3-oxonia-2-boratanaphthalene (DOOB) as fluorescence reagent. The calibration curve for netilmicin in serum is

  6. Kinetic Determination of 2,4-Dichlorophenoxyacetic Acid by Stopped-Flow Fluorescence Polarization Immunoassay

    Microsoft Academic Search

    Sergei A. Eremin; Eugenia G. Matveeva; Augustina Gómez-Hens; Dolores Pérez-Bendito

    1998-01-01

    A kinetic metodology was applied to the determination of 2,4-dichlorophenoxyacetic acid (2,4-D) by using fluorescence polarization immunoassay (FPIA). The analytical parameter used was the initial rate of the antigen-antibody reaction which was obtained from the kinetic curve degree of polarization-time and measured in only 1 s. The stopped-flow mixing technique was used for this purpose which allows the application of

  7. Assay of teicoplanin in serum: comparison of high-performance liquid chromatography and fluorescence polarization immunoassay

    Microsoft Academic Search

    Steven J. McCann; Leslie O. White; Brian Keevil

    A simple liquid extraction coupled with reverse-phase HPLC and UV detection was shown to correlate well with fluorescence polarization immunoassay (FPIA) on the Abbott TDx analyser for serum teicoplanin analysis, r2 = 0.974, HPLC = 0.908 TDx + 2.324. A Bland-Altman plot showed no significant bias between the results. The HPLC method was linear over the range 10-100 mg\\/L. The

  8. Evaluation of fluorescence excitation transfer immunoassay for measurement of specific proteins.

    PubMed

    Calvin, J; Burling, K; Blow, C; Barnes, I; Price, C P

    1986-02-12

    Fluorescence excitation transfer immunoassay is a suitable technique for the measurement of serum IgG and CRP. The reagents, once reconstituted, are stable for at least 3 months. The method shows no interference due to bilirubin, lipaemia or haemolysis up to high levels. The assay is simple to perform, reliable and offers considerable advantages over manual techniques such as radial immunodiffusion or electroimmunoassay. PMID:3511155

  9. A dissociative fluorescence enhancement technique for one-step time-resolved immunoassays

    PubMed Central

    Mukkala, Veli-Matti; Hakala, Harri H. O.; Mäkinen, Pauliina H.; Suonpää, Mikko U.; Hemmilä, Ilkka A.

    2010-01-01

    The limitation of current dissociative fluorescence enhancement techniques is that the lanthanide chelate structures used as molecular probes are not stable enough in one-step assays with high concentrations of complexones or metal ions in the reaction mixture since these substances interfere with lanthanide chelate conjugated to the detector molecule. Lanthanide chelates of diethylenetriaminepentaacetic acid (DTPA) are extremely stable, and we used EuDTPA derivatives conjugated to antibodies as tracers in one-step immunoassays containing high concentrations of complexones or metal ions. Enhancement solutions based on different ?-diketones were developed and tested for their fluorescence-enhancing capability in immunoassays with EuDTPA-labelled antibodies. Characteristics tested were fluorescence intensity, analytical sensitivity, kinetics of complex formation and signal stability. Formation of fluorescent complexes is fast (5 min) in the presented enhancement solution with EuDTPA probes withstanding strong complexones (ethylenediaminetetra acetate (EDTA) up to 100 mM) or metal ions (up to 200 ?M) in the reaction mixture, the signal is intensive, stable for 4 h and the analytical sensitivity with Eu is 40 fmol/L, Tb 130 fmol/L, Sm 2.1 pmol/L and Dy 8.5 pmol/L. With the improved fluorescence enhancement technique, EDTA and citrate plasma samples as well as samples containing relatively high concentrations of metal ions can be analysed using a one-step immunoassay format also at elevated temperatures. It facilitates four-plexing, is based on one chelate structure for detector molecule labelling and is suitable for immunoassays due to the wide dynamic range and the analytical sensitivity. Figure   PMID:21161513

  10. Development of a Prototype Lateral Flow Immunoassay (LFI) for the Rapid Diagnosis of Melioidosis

    PubMed Central

    Houghton, Raymond L.; Reed, Dana E.; Hubbard, Mark A.; Dillon, Michael J.; Chen, Hongjing; Currie, Bart J.; Mayo, Mark; Sarovich, Derek S.; Theobald, Vanessa; Limmathurotsakul, Direk; Wongsuvan, Gumphol; Chantratita, Narisara; Peacock, Sharon J.; Hoffmaster, Alex R.; Duval, Brea; Brett, Paul J.; Burtnick, Mary N.; AuCoin, David P.

    2014-01-01

    Burkholderia pseudomallei is a soil-dwelling bacterium and the causative agent of melioidosis. Isolation of B. pseudomallei from clinical samples is the “gold standard” for the diagnosis of melioidosis; results can take 3–7 days to produce. Alternatively, antibody-based tests have low specificity due to a high percentage of seropositive individuals in endemic areas. There is a clear need to develop a rapid point-of-care antigen detection assay for the diagnosis of melioidosis. Previously, we employed In vivo Microbial Antigen Discovery (InMAD) to identify potential B. pseudomallei diagnostic biomarkers. The B. pseudomallei capsular polysaccharide (CPS) and numerous protein antigens were identified as potential candidates. Here, we describe the development of a diagnostic immunoassay based on the detection of CPS. Following production of a CPS-specific monoclonal antibody (mAb), an antigen-capture immunoassay was developed to determine the concentration of CPS within a panel of melioidosis patient serum and urine samples. The same mAb was used to produce a prototype Active Melioidosis Detect Lateral Flow Immunoassay (AMD LFI); the limit of detection of the LFI for CPS is comparable to the antigen-capture immunoassay (?0.2 ng/ml). The analytical reactivity (inclusivity) of the AMD LFI was 98.7% (76/77) when tested against a large panel of B. pseudomallei isolates. Analytical specificity (cross-reactivity) testing determined that 97.2% of B. pseudomallei near neighbor species (35/36) were not reactive. The non-reactive B. pseudomallei strain and the reactive near neighbor strain can be explained through genetic sequence analysis. Importantly, we show the AMD LFI is capable of detecting CPS in a variety of patient samples. The LFI is currently being evaluated in Thailand and Australia; the focus is to optimize and validate testing procedures on melioidosis patient samples prior to initiation of a large, multisite pre-clinical evaluation. PMID:24651568

  11. Evaluation of the reliability of 6 current anti-HIV1\\/HIV2 enzyme immunoassays

    Microsoft Academic Search

    Bernard Weber; Mahin Moshtaghi-Boronjeni; Michael Brunner; Wolfgang Preiser; Markus Breiner; Hans Wilhelm Doerr

    1995-01-01

    The sensitivity for early detection of HIV antibodies and specificity of 6 anti-HIV-1\\/HIV-2 screening enzyme immunoassays (ELISAs) currently on the market were investigated by testing a panel of 249 well-characterized serum samples. The panel included sera from AIDS patients or children with congenital HIV infection, high-risk individuals and patients with conditions unrelated to AIDS. ‘Tricky’ sera (repeatedly positive results by

  12. Performance of two rapid, single-use immunoassays for the detection of Clostridium difficile toxin A

    Microsoft Academic Search

    Jean Baldus Patel; Angela M. Donahue; Irving Nachamkin

    2001-01-01

    Two rapid, single-use immunoassays for C. difficile toxin A, the Clearview C. DIFF A (Wampole Laboratories, Cranbury, N.J.) and the ImmunoCard Toxin A assays (Meridian Diagnostics Inc., Cincinnati, Ohio) were compared to the cytotoxin assay for their ability to detect C. difficile toxin in fecal specimens. A total of 537 specimens were tested and 47 (8.8%) were positive by the

  13. Magnetic Electrochemical Immunoassays with Quantum Dot Labels for Detection of Phosphorylated Acetylcholinesterase in Plasma

    SciTech Connect

    Wang, Hua; Wang, Jun; Timchalk, Charles; Lin, Yuehe

    2008-11-01

    A new magnetic electrochemical immunoassay has been developed as a tool for biomonitoring exposures to organophosphate (OP) compounds, e.g., insecticides and chemical nerve agents, by directly detecting organophosphorylated acetylcholinesterase (OP?AChE). This immunoassay uniquely incorporates highly efficient magnetic separation with ultrasensitive square wave voltammetry (SWV) analysis with quantum dots (QDs) as labels. A pair of antibodies was used to achieve the specific recognition of OP?AChE that was prepared with paraoxon as an OP model agent. Antiphosphoserine polyclonal antibodies were anchored on amorphous magnetic particles preferably chosen to capture OP?AChE from the sample matrixes by binding their phosphoserine moieties that were exposed through unfolding the protein adducts. This was validated by electrochemical examinations and enzyme-linked immunosorbent assays. Furthermore, antihuman AChE monoclonal antibodies were labeled with cadmium-source QDs to selectively recognize the captured OP?AChE, as characterized by transmission electron microscopy. The subsequent electrochemical SWV analysis of the cadmium component released by acid from the coupled QDs was conducted on disposable screen-printed electrodes. Experimental results indicated that the SWV-based immunoassays could yield a linear response over a broad concentration range of 0.3?300 ng/mL OP?AChE in human plasma with a detection limit of 0.15 ng/mL. Such a novel electrochemical immunoassay holds great promise as a simple, selective, sensitive, and field-deployable tool for the effective biomonitoring and diagnosis of potential exposures to nerve agents and pesticides.

  14. Automation of the enzyme immunoassay for the serodiagnosis of infectious diseases in cattle

    SciTech Connect

    Seawright, G.L.; Sanders, W.M.; Bryson, M.

    1980-01-01

    The enzyme immunoassay (EIA) is a versatile and highly sensitive new tool that can be used to detect a wide variety of infectious diseases or toxic agents and other low molecular weight compound. The paper describes the present state of development of the EIA-modified Technicon Autoanalyzer II instrumentation, standardization of quality control criteria for the automated EIA and standardization of the diagnostic decision process. (ACR)

  15. A New Optical Immunoassay for Detection of S-100B Protein in Whole Blood

    Microsoft Academic Search

    Anna Ettinger; Ayla B. Laumark; Rachel M. Ostroff; Jan Brundell; William A. Baumgartner; Alexander Y. Razumovsky

    2010-01-01

    Background. S-100B is a protein mainly found in astro- glial cells and only detected to a low level in blood. Serum levels of S-100B increase in patients with acute brain injuries. The aim of this study was to establish feasibility of a new Optical ImmunoAssay ((OIA), Bio- Star, Inc, Boulder, CO) test for determination of S-100B in blood. Methods. We

  16. Urinary free light chain analysis by the Freelite immunoassay: a preliminary study in multiple myeloma.

    PubMed

    Le Bricon, Thierry; Bengoufa, Djaouida; Benlakehal, Mourad; Bousquet, Bernard; Erlich, Danielle

    2002-10-01

    Evaluate the Freelite free light chain immunoassay for urine analysis in myeloma. Urine specimens from 20 patients were analyzed by Freelite (The Binding Site) and SDS-agarose gel electrophoresis (Hydragel protéinurie, Sebia). Using the kappa/lambda ratio, Freelite was more sensitive than electrophoresis to detect free light chains, but concentration was overestimated in 75% of cases. Despite high sensitivity and full automation, Freelite inaccurately measures monoclonal free light chains in urine. PMID:12493586

  17. A commercial rapid optical immunoassay detects Streptococcus agalactiae from aquatic cultures and clinical specimens

    Microsoft Academic Search

    Joyce J. Evans; David J. Pasnik; Phillip H. Klesius

    2010-01-01

    The BioStar STREP B Optical ImmunoAssay (STREP B OIA) (BioStar® OIA® Strep B Assay Kit; BioStar Incorporation, Louisville, CO, USA), commonly used for diagnosis of human maternal group B streptococcus (GBS) colonization, was evaluated for its diagnostic and analytical sensitivity and specificity to aquatic animal GBS isolates, cross-reactivity, and diagnosis and recovery of GBS directly from clinically- infected fish swabs.

  18. An integrated, stacked microlaboratory for biological agent detection with DNA and immunoassays

    Microsoft Academic Search

    Joon Mo Yang; Janice Bell; Ying Huang; Marcus Tirado; Donald Thomas; Anita H Forster; Robert W Haigis; Paul D Swanson; R. Bruce Wallace; Bob Martinsons; Michael Krihak

    2002-01-01

    An integrated, stacked microlaboratory for performing automated electric-field-driven immunoassays and DNA hybridization assays was developed. The stacked microlaboratory was fabricated by orderly laminating several different functional layers (all 76×76 mm2) including a patterned polyimide layer with a flip-chip bonded CMOS chip, a pressure sensitive acrylic adhesive (PSA) layer with a fluidic cutout, an optically transparent polymethyl methacrylate (PMMA) film, a

  19. Multiplex ready flow cytometric immunoassay for total insulin like growth factor 1 in serum of cattle.

    PubMed

    Bremer, Maria Gabriëlle Eleonore Gerarda; Smits, Nathalie Gabriëlle Esther; Haasnoot, Willem; Nielen, Michel Wilhelmus Franciscus

    2010-05-01

    The European Union has banned the use of recombinant bovine somatotropins (rbST, growth hormones) to increase milk yield in dairy cattle. As direct detection of rbST in serum is problematic, methods based on the detection of changes in multiple rbST-dependent biomarkers have high potential for monitoring rbST abuse. In this study immunoassays were developed for total insulin-like growth factor 1 (IGF-1) in cow sera. Ultimately aiming at combination with other rbST-dependent biomarker assays two multiplex formats were studied and compared critically, a multi-channel surface plasmon resonance (SPR)-based biosensor and flow cytometry combined with color encoded microbeads. Moreover, a new dedicated sample pretreatment was developed for the dissociation of complexed IGF-1 in serum, while keeping other biomarkers in solution. Compared to the SPR biosensor immunoassay, the flow cytometric immunoassay (FCIA) was more sensitive, less antibody-consuming and less vulnerable to necessary but interfering reagents from the sample treatment. In an initial in-house validation study the developed FCIA showed to be fast, specific, robust, and a high repeatability and reliability, and generated realistic IGF-1 values for bovine serum, without compromising the potential for simultaneous detection of other biomarkers. Due to the xMAP technology, in which 100 different bead sets can be measured simultaneously, the total IGF-1 assay can easily be extended with other immunoassays for candidate biomarkers. Preliminary results about a FCIA for IGF-1 multiplexing with insulin-like growth factor binding protein 2 (IGFBP2) are presented which strongly supported both the FCIA multiplex format as well as the generic nature of the developed sample pretreatment. PMID:20419268

  20. European Multicenter Evaluation of Commercial Enzyme Immunoassays for Detecting Norovirus Antigen in Fecal Samples

    Microsoft Academic Search

    Jim J. Gray; Evelyne Kohli; Franco M. Ruggeri; Harry Vennema; Alicia Sanchez-Fauquier; Eckart Schreier; Chris I. Gallimore; Miren Iturriza-Gomara; Helene Giraudon; Pierre Pothier; I. Di Bartolo; N. Inglese; E. de Bruin; B. van der Veer; S. Moreno; V. Montero; M. C. de Llano; M. Hohne; S. M. Diedrich

    2007-01-01

    A total of 2,254 fecal samples were tested in a European multicenter evaluation of commercially available norovirus antigen detection assays. Two commercial enzyme immunoassays, IDEIA Norovirus (Oxoid; Thermo Fisher Scientific, Ely, United Kingdom) and RIDASCREEN Norovirus (R-Biopharm, Darmstadt, Germany), were included in the evaluation, and their performance was compared with the results of reverse transcription- PCR (RT-PCR). Included in the

  1. Evaluation of a commercial enzyme immunoassay for detection of norovirus in outbreak specimens

    Microsoft Academic Search

    A. Dimitriadis; J. A. Marshall

    2005-01-01

    The aim of the study presented here was to use faeces from 41 gastroenteritis outbreaks (130 specimens) in Victoria, Australia,\\u000a to evaluate the sensitivity and specificity of the RIDASCREEN norovirus enzyme immunoassay (EIA) kit relative to reverse transcription-polymerase\\u000a chain reaction and\\/or electron microscopy. Seven specimens known to contain sapovirus, adenovirus, astrovirus and rotavirus\\u000a were also tested. For single-specimen diagnosis the

  2. Wick Chromatography for Rapid and Reliable Immunoassay of Insulin, Glucagon and Growth Hormone

    Microsoft Academic Search

    Hans Ørskov; Hans Grønlund Thomsen; Hans Yde

    1968-01-01

    THE essential principle of competition for a given amount of anti-hormone between standard or unknown quantities of hormone and a fixed amount of labelled hormone in Yalow and Berson's1 radio-immunoassay has been maintained in all modifications. The modifications have simplified the apparatus and have achieved a more rapid and complete separation of free and antibody-bound radioactive hormone after the immunological

  3. Improving of enzyme immunoassay for detection and quantification of the target molecules using silver nanoparticles

    NASA Astrophysics Data System (ADS)

    Syrvatka, Vasyl J.; Slyvchuk, Yurij I.; Rozgoni, Ivan I.; Gevkan, Ivan I.; Overchuk, Marta O.

    2014-02-01

    Modern routine enzyme immunoassays for detection and quantification of biomolecules have several disadvantages such as high cost, insufficient sensitivity, complexity and long-term execution. The surface plasmon resonance of silver nanoparticles gives reasons of creating new in the basis of simple, highly sensitive and low cost colorimetric assays that can be applied to the detection of small molecules, DNA, proteins and pollutants. The main aim of the study was the improving of enzyme immunoassay for detection and quantification of the target molecules using silver nanoparticles. For this purpose we developed method for synthesis of silver nanoparticles with hyaluronic acid and studied possibility of use these nanoparticles in direct determination of target molecules concentration (in particular proteins) and for improving of enzyme immunoassay. As model we used conventional enzyme immunoassays for determination of progesterone and estradiol concentration. We obtained the possibility to produce silver nanoparticles with hyaluronan homogeneous in size between 10 and 12 nm, soluble and stable in water during long term of storage using modified procedure of silver nanoparticles synthesis. New method allows to obtain silver nanoparticles with strong optical properties at the higher concentrations - 60-90 ?g/ml with the peak of absorbance at the wavelength 400 nm. Therefore surface plasmon resonance of silver nanoparticles with hyaluronan and ultraviolet-visible spectroscopy provide an opportunity for rapid determination of target molecules concentration (especial protein). We used silver nanoparticles as enzyme carriers and signal enhancers. Our preliminary data show that silver nanoparticles increased absorbance of samples that allows improving upper limit of determination of estradiol and progesterone concentration.

  4. Rapid microchip-based electrophoretic immunoassays for the detection of swine influenza virus.

    PubMed

    Reichmuth, David S; Wang, Serena K; Barrett, Louise M; Throckmorton, Daniel J; Einfeld, Wayne; Singh, Anup K

    2008-08-01

    Towards developing rapid and portable diagnostics for detecting zoonotic diseases, we have developed microchip-based electrophoretic immunoassays for sensitive and rapid detection of viruses. Two types of microchip-based electrophoretic immunoassays were developed. The initial assay used open channel electrophoresis and laser-induced fluorescence detection with a labeled antibody to detect influenza virus. However, this assay did not have adequate sensitivity to detect viruses at relevant concentrations for diagnostic applications. Hence, a novel assay was developed that allows simultaneous concentration and detection of viruses using a microfluidic chip with an integrated nanoporous membrane. The size-exclusion properties of the in situ polymerized polyacrylamide membrane are exploited to simultaneously concentrate viral particles and separate the virus/fluorescent antibody complex from the unbound antibody. The assay is performed in two simple steps--addition of fluorescently labeled antibodies to the sample, followed by concentration of antibody-virus complexes on a porous membrane. Excess antibodies are removed by electrophoresis through the membrane and the complex is then detected downstream of the membrane. This new assay detected inactivated swine influenza virus at a concentration four times lower than that of the open-channel electrophoresis assay. The total assay time, including device regeneration, is six minutes and requires <50 microl of sample. The filtration effect of the polymer membrane eliminates the need for washing, commonly required with surface-based immunoassays, increasing the speed of the assay. This assay is intended to form the core of a portable device for the diagnosis of high-consequence animal pathogens such as foot-and-mouth disease. The electrophoretic immunoassay format is rapid and simple while providing the necessary sensitivity for diagnosis of the illness state. This would allow the development of a portable, cost-effective, on-site diagnostic system for rapid screening of large populations of livestock, including sheep, pigs, cattle, and potentially birds. PMID:18651074

  5. Cell-based immobilization strategy for sensitive piezoelectric immunoassay of total prostate specific antigen

    Microsoft Academic Search

    Yanjun Ding; Haixia Lu; Guorong Shi; Jia Liu; Guoli Shen; Ruqin Yu

    2008-01-01

    A novel yeast cell-based strategy for the immobilization of antibodies using an amine-terminated self-assembly film has been proposed. A quartz crystal microbalance sensor was according fabricated by coupling with anti-prostate specific antigen (anti-PSA) for PSA immunoassay. The crystal was modified with cysteamine to deposit yeast cells, on which anti-PSA antibodies were immobilized. The surface topologies of the as-prepared crystals were

  6. Evaluation of a Combination Rapid Immunoassay for Detection of Giardia and Cryptosporidium Antigens

    PubMed Central

    Chan, Raymond; Chen, Jing; York, Mary K.; Setijono, Norman; Kaplan, Raymond L.; Graham, Fitzroy; Tanowitz, Herbert B.

    2000-01-01

    A combination cassette format nonenzymatic rapid immunoassay for detection of Giardia and Cryptosporidium antigens was evaluated by using 556 patient stool specimens from three clinical laboratories. This assay (Genzyme Diagnostics Contrast Giardia/Cryptosporidium), which can be used with fresh or formalin-fixed specimens, had unadjusted sensitivities and specificities of 96.1 and 98.5% for Giardia and 100 and 98.7% for Cryptosporidium, respectively, in this study. PMID:10618122

  7. Multiplexed electrochemical immunoassay of biomarkers using metal sulfide quantum dot nanolabels and trifunctionalized magnetic beads.

    PubMed

    Tang, Dianping; Hou, Li; Niessner, Reinhard; Xu, Mingdi; Gao, Zhuangqiang; Knopp, Dietmar

    2013-08-15

    A novel multiplexed stripping voltammetric immunoassay protocol was designed for the simultaneous detection of multiple biomarkers (CA 125, CA 15-3, and CA 19-9 used as models) using PAMAM dendrimer-metal sulfide quantum dot (QD) nanolabels as distinguishable signal tags and trifunctionalized magnetic beads as an immunosensing probe. The probe was prepared by means of co-immobilization of primary monoclonal anti-CA 125, anti-CA 15-3 and anti-CA 19-9 antibodies on a single magnetic bead. The PAMAM dendrimer-metal sulfide QD nanolabels containing CdS, ZnS and PbS were synthesized by using in situ synthesis method, which were utilized for the labeling of polyclonal rabbit anti-CA 125, anti-CA 15-3 and anti-CA 19-9 detection antibodies, respectively. A sandwich-type immunoassay format was adopted for the simultaneous determination of target biomarkers in a low-binding microtiter plate. The subsequent anodic stripping voltammetric analysis of cadmium, zinc, and lead components released by acid from the corresponding QD nanolabels was conducted at an in situ prepared mercury film electrode based on the difference of peak potentials. Experimental results indicated that the multiplexed immunoassay enabled the simultaneous detection of three cancer biomarkers in a single run with wide dynamic ranges of 0.01-50 U mL(-1) and detection limits (LODs) of 0.005 U mL(-1). Intra-assay and inter-assay coefficients of variation (CVs) were less than 7.2% and 10.4%, respectively. No significant differences at the 0.05 significance level were encountered in the analysis of 10 clinical serum specimens between the multiplexed immunoassay and a commercially available enzyme-linked immunosorbent assay (ELISA). PMID:23500474

  8. Evaluation of a new particle gel immunoassay for determination of antibodies against Treponema pallidum.

    PubMed

    Schmidt, Bruno L

    2004-06-01

    A new particle gel immunoassay (DiaMed AG, Cressier sur Morat, Switzerland) with three recombinant Treponema pallidum antigens was evaluated with serum samples from patients with syphilis (n = 124) and patients without syphilis (n = 490). It proved to be a simple, rapid (20 min), and useful test with sensitivity, specificity, and positive and negative predictive values of 91.9, 99.8, 99.2, and 98%, respectively. PMID:15184485

  9. Cytomegalovirus Antibody in Cerebrospinal Fluid of Schizophrenic Patients Detected by Enzyme Immunoassay

    NASA Astrophysics Data System (ADS)

    Fuller Torrey, E.; Yolken, Robert H.; Winfrey, C. Jack

    1982-05-01

    By means of enzyme immunoassay techniques to detect the presence of antibody to cytomegalovirus, the cerebrospinal fluid of 178 patients with schizophrenia, 17 patients with bipolar disorders, and 11 other psychiatric patients was compared with that of 79 neurological patients and 41 normal control subjects. The cerebrospinal fluid of 20 of the schizophrenic patients and 3 of the patients with bipolar disorders showed significant increases in immunoglobulin M antibody to cytomegalovirus; no difference was found in patients on or off psychotropic medications.

  10. Progress in enzyme immunoassays: production of reagents, experimental design, and interpretation*

    PubMed Central

    Kurstak, Edouard

    1985-01-01

    Enzyme immunoassays represent in many cases the preferred procedure for the detection of antigens or corresponding antibodies. However, many of the current procedures are performed suboptimally. This article reviews the available designs, auxiliary recognition systems, production and purification of antibodies, conjugation procedures, solid-phase materials, recording and interpretation of results, and quality control and standardization of procedures to improve the reproducibility of tests. PMID:3910300

  11. Negative Interference in Cardiac Troponin I Immunoassays from a Frequently Occurring Serum and Plasma Component

    Microsoft Academic Search

    Susann Eriksson; Miia Junikka; Paivi Laitinen; Kirsi Majamaa-Voltti; Henrik Alfthan; Kim Pettersson

    2003-01-01

    Background: Cardiac troponin I (cTnI) is a sensitive marker of cardiac injury, but cTnI assays, like other immunoassays, are susceptible to interferences. We evaluated the presence of interfering substances by measuring the recovery of cTnI added to samples from volunteers and from patients with acute coronary syn- dromes (ACS). Methods: We added a ternary complex of human cardiac troponin (30

  12. A competitive enzyme immunoassay for the quantitative detection of cocaine from banknotes and latent fingermarks.

    PubMed

    van der Heide, Susan; Garcia Calavia, Paula; Hardwick, Sheila; Hudson, Simon; Wolff, Kim; Russell, David A

    2015-05-01

    A sensitive and versatile competitive enzyme immunoassay (cEIA) has been developed for the quantitative detection of cocaine in complex forensic samples. Polyclonal anti-cocaine antibody was purified from serum and deposited onto microtiter plates. The concentration of the cocaine antibody adsorbed onto the plates, and the dilution of the cocaine-HRP hapten were both studied to achieve an optimised immunoassay. The method was successfully used to quantify cocaine in extracts taken from both paper currency and latent fingermarks. The limit of detection (LOD) of 0.162ngmL(-1) achieved with the assay compares favourably to that of conventional chromatography-mass spectroscopy techniques, with an appropriate sensitivity for the quantification of cocaine at the low concentrations present in some forensic samples. The cEIA was directly compared to LC-MS for the analysis of ten UK banknote samples. The results obtained from both techniques were statistically similar, suggesting that the immunoassay was unaffected by cross-reactivity with potentially interfering compounds. The cEIA was used also for the detection of cocaine in extracts from latent fingermarks. The results obtained were compared to the cocaine concentrations detected in oral fluid sampled from the same individual. Using the cEIA, we have shown, for the first time, that endogeneously excreted cocaine can be detected and quantified from a single latent fingermark. Additionally, it has been shown that the presence of cocaine, at similar concentrations, in more than one latent fingermark from the same individual can be linked with those concentrations found in oral fluid. These results show that detection of drugs in latent fingermarks could directly indicate whether an individual has consumed the drug. The specificity and feasibility of measuring low concentrations of cocaine in complex forensic samples demonstrate the effectiveness and robustness of the assay. The immunoassay presents a simple and cost-effective alternative to the current mass spectrometry based techniques for the quantitation of cocaine at forensically significant concentrations. PMID:25766738

  13. A multi?residue enzyme immunoassay for screening illegally used ??agonists

    Microsoft Academic Search

    Inge Dürsch; Heinrich H. D. Meyer

    1992-01-01

    A multi?residue screening test was developed which provides reliable detection of eight ß?agonists in urine, based on an enzyme immunoassay with peroxidase and an antibody raised against clenbuterol?diazo?BSA. Antibodies were compared after continuous immunization. The antibody obtained after the 12th immunization showed the best sensitivity, procedural blanks of urine samples and coefficients of variation, using analysis of spiked urine samples.

  14. Detection of drug usage via breath analysis with an immunoassay film badge

    NASA Astrophysics Data System (ADS)

    Lukens, Herbert R.

    1997-01-01

    A monolayer of antibody on a semimirror comprised of small islands of indium acts as a sensor capable of detecting vapors at extremely low concentrations without the use of wet chemistry. Already shown capable of detecting cocaine vapors at 4 femtograms per cc of air, the use of the device, called an immunoassay film badge, for detecting drugs on the breath is a natural extension of the sensor's use. This paper describes this application and initial experiments that demonstrate its feasibility.

  15. Development and comparison of two immunoassay formats for rapid detection of botulinum neurotoxin type A

    Microsoft Academic Search

    Olivier Attrée; Valérie Guglielmo-Viret; Valérie Gros; Philippe Thullier

    2007-01-01

    We have evaluated two formats of immunoassays for the rapid detection of Clostridium botulinum neurotoxin type A (BoNT\\/A), in assay buffer and various matrices (human serum and nasal swabs, fresh milk, sugar, flour and talcum). The two formats, a vertical-flow strip immunochromatography (ICT) and a small disposable immunoaffinity column (IAC), were selected because they are both rapid and readily usable

  16. Surface electrochemical enzyme immunoassay for the highly sensitive measurement of B-type natriureric peptide

    Microsoft Academic Search

    Hiroaki Matsuura; Yukari Sato; Osamu Niwa; Fumio Mizutani

    2005-01-01

    B-type natriuretic peptide (BNP), a peptide hormone, was determined by electrochemical enzyme immunoassay through the following procedure. First, a certain concentration of sample BNP was added to the solution containing anti-BNP antibody modified with acetylcholinesterase (AChE) to undergo the immunological reaction. Then BNP-modified gold particles were added into the BNP\\/AChE-labeled anti-BNP antibody solution so that the unreacted AChE-labeled anti-BNP antibody

  17. An immunoassay using antibody-gold nanoparticle conjugate, silver enhancement and flatbed scanner

    Microsoft Academic Search

    Chia-Hsien Yeh; Ching-Yuan Hung; Tsung Chain Chang; Hong-Ping Lin; Yu-Cheng Lin

    2009-01-01

    This study reports a convenient immunoassay using antibody-gold nanoparticle (Ab-AuNP) conjugate as a reporter molecule and\\u000a a flatbed scanner for the optical scanning and measuring of the immuno-reaction signal. The silver enhancement reaction, a\\u000a signal amplification method in which silver ions are reduced to silver metal, is introduced to magnify the detection signal.\\u000a The whole framework of the study is

  18. Typing of Human Astroviruses from Clinical Isolates by Enzyme Immunoassay and Nucleotide Sequencing

    Microsoft Academic Search

    JACQUELINE S. NOEL; TERRY W. LEE; JOHN B. KURTZ; ROGER I. GLASS

    1995-01-01

    A typing enzyme immunoassay (TYPE-EIA) was used to determine the antigenic types of 64 astrovirus- positive specimens from nine collections from seven countries. Six of the seven known astrovirus types were detected in the collections, with HAstV-1 predominating in all collections except for one from the United Kingdom. Selected specimens were analyzed further by reverse transcriptase PCR and nucleotide sequencing

  19. Solidphase enzyme-immunoassay for detection of hepatitis B surface antigen

    Microsoft Academic Search

    G Wolters; L Kuijpers; J Kacaki; A Schuurs

    1976-01-01

    The preliminary results of a solid-phase enzyme-immunoassay (EIA) for the detection of hepatitis B surface antigen (HBsAg) are presented. This method has been compared with the solid-phase radioimmunoassay (RIA) for HBsAg in dilution series of four HBsAg positive sera four national reference panels (The Laboratory Panel of the Central Laboratory of the Blood Transfusion Service of the Netherlands Red Cross,

  20. Role of immunoassay in the analysis of microcontaminants in water samples

    Microsoft Academic Search

    G. W. Aherne; J. English; V. Marks

    1985-01-01

    Concentrations of natural and synthetic steroids and an anticancer drug (methotrexate) have been determined in water by adapting established immunoassay procedures. The limits of detection for the assays used were 10 ng\\/liter for norethisterone, 5 ng\\/liter for ethinyl estradiol and progesterone, and 6.25 ng\\/liter for methotrexate. Results below the level of detection were obtained in all the samples examined (8