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Sample records for phenolphthalein

  1. Plasticized phenolphthalein polycarbonate

    NASA Technical Reports Server (NTRS)

    Harrison, E. S.

    1976-01-01

    Phenolphthalein polycarbonate was successfully plasticized with polychlorinated biphenyls (e.g., Aroclor 1231) or tricresyl phosphate and cast from tetrahydrofuran to give clear films without loss of fire resistance. At loadings of 20 to 30 percent plasticizer the Tg was lowered to approximately 100 C which would render phenolphthalein polycarbonate easily moldable. Although these materials had some mechanical integrity as shown by their film forming ability, the room temperature toughness of the plasticized polymer was not significantly improved over unmodified polymer.

  2. Reactions of Phenolphthalein at Various pH Values.

    ERIC Educational Resources Information Center

    Wittke, Georg

    1983-01-01

    Reactions of phenolphthalein with sodium hydroxide and sulfuric are discussed. Also discusses the sulfonation of phenolphthalein, listing experimental results related to the sulfonation reaction. (JN)

  3. Synthesis of optically clear polymeric materials for high temperature windows. [preparation of phenolphthalein polycarbonate resin

    NASA Technical Reports Server (NTRS)

    Pannell, C. E.; Magner, J. E.

    1973-01-01

    A polymer has been developed that has excellent potential for use as windows in spacecraft as well as conventional aircraft. This polymer, phenolphthalein polycarbonate, has outstanding thermal properties, e.g., in place of melting or burning, it produces an insulating charred foam that closes off transmission of radiant heat through the window. This fact, coupled with an oxygen index of 0.43 and a 177 C tensile strength of 58 mega Newtons/sq m, makes this polymer a prime candidate for further development. Pilot plant preparation in a 20 gallon Pfaudler kettle was accomplished and large test specimens were prepared for evaluations.

  4. Detection and quantitation of trace phenolphthalein (in pharmaceutical preparations and in forensic exhibits) by liquid chromatography-tandem mass spectrometry, a sensitive and accurate method.

    PubMed

    Sharma, Kakali; Sharma, Shiba P; Lahiri, Sujit C

    2013-01-01

    Phenolphthalein, an acid-base indicator and laxative, is important as a constituent of widely used weight-reducing multicomponent food formulations. Phenolphthalein is an useful reagent in forensic science for the identification of blood stains of suspected victims and for apprehending erring officials accepting bribes in graft or trap cases. The pink-colored alkaline hand washes originating from the phenolphthalein-smeared notes can easily be determined spectrophotometrically. But in many cases, colored solution turns colorless with time, which renders the genuineness of bribe cases doubtful to the judiciary. No method is known till now for the detection and identification of phenolphthalein in colorless forensic exhibits with positive proof. Liquid chromatography-tandem mass spectrometry had been found to be most sensitive, accurate method capable of detection and quantitation of trace phenolphthalein in commercial formulations and colorless forensic exhibits with positive proof. The detection limit of phenolphthalein was found to be 1.66 pg/L or ng/mL, and the calibration curve shows good linearity (r(2) = 0.9974). PMID:23106487

  5. Coloring Rate of Phenolphthalein by Reaction with Alkaline Solution Observed by Liquid-Droplet Collision.

    PubMed

    Takano, Yuuka; Kikkawa, Shigenori; Suzuki, Tomoko; Kohno, Jun-ya

    2015-06-11

    Many important chemical reactions are induced by mixing two solutions. This paper presents a new way to measure rates of rapid chemical reactions induced by mixing two reactant solutions using a liquid-droplet collision. The coloring reaction of phenolphthalein (H2PP) by a reaction with NaOH is investigated kinetically. Liquid droplets of H2PP/ethanol and NaOH/H2O solutions are made to collide, which induces a reaction that transforms H2PP into a deprotonated form (PP(2-)). The concentration of PP(2-) is evaluated from the RGB values of pixels in the colored droplet images, and is measured as a function of the elapsed time from the collision. The obtained rate constant is (2.2 ± 0.7) × 10(3) M(-1) s(-1), which is the rate constant for the rate-determining step of the coloring reaction of H2PP. This method was shown to be applicable to determine rate constants of rapid chemical reactions between two solutions.

  6. Technical note: The effects of Bluestar(®) and luminol when used in conjunction with tetramethylbenzidine or phenolphthalein.

    PubMed

    Luedeke, Makayla; Miller, Emily; Sprague, Jon E

    2016-05-01

    There are numerous presumptive tests available in the forensic science field to help identify the presence of blood. While many articles are available on the effects of Bluestar(®) and luminol and potential interactions with subsequent DNA identification, the research field falls short in identifying the effects these two presumptive tests may have on subsequent presumptive tests used to help identify blood. To rectify this ongoing issue in the forensic science field, the chemiluminescence methods of Bluestar(®) and luminol for the detection of blood at a crime scene were tested for their effects when used in conjunction with tetramethylbenzidine (TMB) or phenolphthalein (PT) at the forensic science laboratory. Six different substrates (untreated wood, pressure treated wood, ceramic tile, shag carpet, cement block, and cotton clothing) were stained with varying dilutions (range 1:1 to 1:100,000) of blood. Neither luminol nor Bluestar(®) affect the results of PT or TMB tests at blood dilutions equal to or less than 1:100. However, interactions did occur between agents and substrates with blood dilutions 1:1000 or greater. Bluestar(®) was the only presumptive test that can detect blood dilutions of 1:100,000 on some substrates and luminol was inclusive on pressure treated wood. These findings suggests that forensic science laboratory personal need to know and understand the details of how the blood was detected by the crime scene investigator and the substrate on which the blood was obtained from for their preparation of presumptive blood testing with PT or TMB. PMID:26990564

  7. Phenolphthalein-based Poly(arylene ether sulfone nitrile)s Multiblock Copolymers As Anion Exchange Membranes for Alkaline Fuel Cells.

    PubMed

    Lai, Ao Nan; Wang, Li Sha; Lin, Chen Xiao; Zhuo, Yi Zhi; Zhang, Qiu Gen; Zhu, Ai Mei; Liu, Qing Lin

    2015-04-22

    A series of phenolphthalein-based poly(arylene ether sulfone nitrile)s (PESN) multiblock copolymers containing 1-methylimidazole groups (ImPESN) were synthesized to prepare anion exchange membranes (AEMs) for alkaline fuel cells. The ion groups were introduced selectively and densely on the unit of phenolphthalein as the hydrophilic segments, allowing for the formation of ion clusters. Strong polar nitrile groups were introduced into the hydrophobic segments with the intention of improving the dimensional stability of the AEMs. A well-controlled multiblock structure was responsible for the well-defined hydrophobic/hydrophilic phase separation and interconnected ion-transport channels, as confirmed by atomic force microscopy and small angle X-ray scattering. The ImPESN membranes with low swelling showed a relatively high water uptake, high hydroxide ion conductivity together with good mechanical, thermal and alkaline stability. The ionic conductivity of the membranes was in the range of 3.85-14.67×10(-2) S·cm(-1) from 30 to 80 °C. Moreover, a single H2/O2 fuel cell with the ImPESN membrane showed an open circuit voltage of 0.92 V and a maximum power density of 66.4 mW cm(-2) at 60 °C.

  8. Color indicator for supramolecular polymer chemistry: phenolphthalein-containing thermo- and pH-sensitive N-(Isopropyl)acrylamide copolymers and β-cyclodextrin complexation.

    PubMed

    Fleischmann, Carolin; Ritter, Helmut

    2013-07-12

    The copolymerization parameters of N-(isopropyl)acrylamide (1) and N-(2-hydroxy-5-(1-(4-hydroxyphenyl)-3-oxo-1,3-dihydroisobenzofuran-1-yl)benzyl)acrylamide (2) are determined. For both monomers, the homoaddition proceeds slightly faster than the heteroaddition step; however, the polymer formation occurs in a statistic fashion. Copolymers of different compositions are prepared and the cloud points are determined. Thereby, a significant influence of the concentration of monomer 2 and the pH value is found. For the first time, the complexation of polymer attached phenolphthalein by β-cyclodextrins is shown. Furthermore, it is possible to achieve a decomplexation by the addition of suitable guest molecules. Both procedures can be followed with the naked eye.

  9. Phenolphthalein-Pink Tornado Demonstration

    ERIC Educational Resources Information Center

    Prall, Bruce R.

    2008-01-01

    The titration of HCl with NaOH has traditionally been used to introduce beginning chemistry students to the concepts of acid-base chemistry and stoichiometry. The demonstration described in this article utilizes this reaction as a means of providing students an opportunity to observe the dynamic motion associated with a swirling vortex and its…

  10. Kinetics of the Fading of Phenolphthalein in Alkaline Solution.

    ERIC Educational Resources Information Center

    Nicholson, Lois

    1989-01-01

    Described is an experiment which illustrates pseudo-first-order kinetics in the fading of a common indicator in an alkaline solution. Included are background information, details of materials used, laboratory procedures, and sample results. (CW)

  11. Molecular Recognition: Detection of Colorless Compounds Based on Color Change

    ERIC Educational Resources Information Center

    Khalafi, Lida; Kashani, Samira; Karimi, Javad

    2016-01-01

    A laboratory experiment is described in which students measure the amount of cetirizine in allergy-treatment tablets based on molecular recognition. The basis of recognition is competition of cetirizine with phenolphthalein to form an inclusion complex with ß-cyclodextrin. Phenolphthalein is pinkish under basic condition, whereas it's complex form…

  12. The Best Enzyme Investigation Ever? Probably.

    ERIC Educational Resources Information Center

    Cooper, Phil

    2000-01-01

    Uses alkaline phosphate to remove the phosphate group from phenolphthalein diphosphate. Discusses problems which include the interference of ambient light and temperature variation. Provides detailed information about the apparatus and the experimental procedure. (ASK)

  13. Demonstrating Diffusion

    ERIC Educational Resources Information Center

    Foy, Barry G.

    1977-01-01

    Two demonstrations are described. Materials and instructions for demonstrating movement of molecules into cytoplasm using agar blocks, phenolphthalein, and sodium hydroxide are given. A simple method for demonstrating that the rate of diffusion of a gas is inversely proportional to its molecular weight is also presented. (AJ)

  14. The Plague Generation.

    ERIC Educational Resources Information Center

    Jones, Richard C.

    1993-01-01

    Describes an activity to simulate the geometries of a spreading pathogen such as HIV throughout a generation. Students exchange "bodily fluids" three times and are then tested for the presence of "infection." Materials used include base solutions (NaOH or KOH), phenolphthalein (pH indicator), clear plastic cups, and an eye dropper. (PR)

  15. "Mud" + "Blood"--A Very Colorful Demonstration.

    ERIC Educational Resources Information Center

    Hambly, Gordon

    1998-01-01

    Describes a demonstration in which a bloodred-colored solution of hydrogen peroxide, sodium hydroxide, and phenolphthalein indicator is added to a mud-colored solution of potassium permanganate, hydrated manganous chloride, and sulfuric acid. The mixture turns clear when added together. Draws parallels between the demonstration and the Old…

  16. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Kolb, Doris, Ed.

    1989-01-01

    Described are three chemistry demonstrations: (1) a simple qualitative technique for taste pattern recognition in structure-activity relationships; (2) a microscale study of gaseous diffusion using bleach, HCl, ammonia, and phenolphthalein; and (3) the rotation of polarized light by stereoisomers of limonene. (MVL)

  17. Initial evaluation tests of General Electric Company 12.0 ampere hour nickel cadmium spacecraft cells with design variables

    NASA Technical Reports Server (NTRS)

    Harkness, J. D.

    1979-01-01

    All evaluation tests were performed at room ambient pressure and temperature, with discharges at a 2 hour rate. Tests consisted of phenolphthalein leak tests, three capacity tests, an auxiliary electrode test, a charge retention test, an internal short test, a charge efficiency test, overcharge tests, and a pressure versus capacity test. Results of the tests and recommendations for improvements in manufacturing are presented.

  18. Colorblindness and Titrations with Visual Indicators.

    ERIC Educational Resources Information Center

    Diehl, Harvey; And Others

    1985-01-01

    Discusses various issues related to colorblind students performing titrations with visual indicators. Includes tables showing precisions in the titration of a weak acid by colorblind students using phenolphthalein and thymolphthalein and in the titration of a weak base by colorblind persons using methyl red and bromcresol green. (JN)

  19. Attempts to develop a new nuclear measurement technique of β-glucuronidase levels in biological samples

    NASA Astrophysics Data System (ADS)

    Ünak, T.; Avcibasi, U.; Yildirim, Y.; Çetinkaya, B.

    2003-01-01

    β-Glucuronidase is one of the most important hydrolytic enzymes in living systems and plays an essential role in the detoxification pathway of toxic materials incorporated into the metabolism. Some organs, especially liver and some tumour tissues, have high level of β-glucuronidase activity. As a result the enzymatic activity of some kind of tumour cells, the radiolabelled glucuronide conjugates of cytotoxic, as well as radiotoxic compounds have potentially very valuable diagnostic and therapeutic applications in cancer research. For this reason, a sensitive measurement of β-glucuronidase levels in normal and tumour tissues is a very important step for these kinds of applications. According to the classical measurement method of β-glucuronidase activity, in general, the quantity of phenolphthalein liberated from its glucuronide conjugate, i.e. phenolphthalein-glucuronide, by β-glucuronidase has been measured by use of the spectrophotometric technique. The lower detection limit of phenolphthalein by the spectrophotometric technique is about 1 3 μg. This means that the β-glucuronidase levels could not be detected in biological samples having lower levels of β-glucuronidase activity and therefore the applications of the spectrophotometric technique in cancer research are very seriously limited. Starting from this consideration, we recently attempted to develop a new nuclear technique to measure much lower concentrations of β-glucuronidase in biological samples. To improve the detection limit, phenolphthalein-glucuronide and also phenyl-N-glucuronide were radioiodinated with 131I and their radioactivity was measured by use of the counting technique. Therefore, the quantity of phenolphthalein or aniline radioiodinated with 131I and liberated by the deglucuronidation reactivity of β-glucuronidase was used in an attempt to measure levels lower than the spectrophotometric measurement technique. The results obtained clearly verified that 0.01 pg level of

  20. Attempts to develop a new nuclear measurement technique of β-glucuronidase levels in biological samples

    NASA Astrophysics Data System (ADS)

    Ünak, T.; Avcibasi, U.; Yildirim, Y.; Çetinkaya, B.

    2003-01-01

    β-Glucuronidase is one of the most important hydrolytic enzymes in living systems and plays an essential role in the detoxification pathway of toxic materials incorporated into the metabolism. Some organs, especially liver and some tumour tissues, have high level of β-glucuronidase activity. As a result the enzymatic activity of some kind of tumour cells, the radiolabelled glucuronide conjugates of cytotoxic, as well as radiotoxic compounds have potentially very valuable diagnostic and therapeutic applications in cancer research. For this reason, a sensitive measurement of β-glucuronidase levels in normal and tumour tissues is a very important step for these kinds of applications. According to the classical measurement method of β-glucuronidase activity, in general, the quantity of phenolphthalein liberated from its glucuronide conjugate, i.e. phenolphthalein-glucuronide, by β-glucuronidase has been measured by use of the spectrophotometric technique. The lower detection limit of phenolphthalein by the spectrophotometric technique is about 1-3 μg. This means that the β-glucuronidase levels could not be detected in biological samples having lower levels of β-glucuronidase activity and therefore the applications of the spectrophotometric technique in cancer research are very seriously limited. Starting from this consideration, we recently attempted to develop a new nuclear technique to measure much lower concentrations of β-glucuronidase in biological samples. To improve the detection limit, phenolphthalein-glucuronide and also phenyl-N-glucuronide were radioiodinated with 131I and their radioactivity was measured by use of the counting technique. Therefore, the quantity of phenolphthalein or aniline radioiodinated with 131I and liberated by the deglucuronidation reactivity of β-glucuronidase was used in an attempt to measure levels lower than the spectrophotometric measurement technique. The results obtained clearly verified that 0.01 pg level of

  1. Assessment of relative flammability and thermochemical properties of some thermoplastic materials

    NASA Technical Reports Server (NTRS)

    Kourtides, D. A.; Parker, J. A.

    1978-01-01

    The thermochemical and flammability characteristics of some typical thermoplastic materials currently in use and others being considered for use in aircraft interiors are described. The properties studied included (1) thermal mechanical properties such as glass transition and melt temperature, (2) changes in polymer enthalpy by differential scanning calorimetry, (3) thermogravimetric analysis in an anaerobic and oxidative environment, (4) oxygen index, (5) smoke evolution, (6) relative toxicity of the volatile products of pyrolysis, and (7) selected physical properties. The generic polymers which were evaluated included: acrylonitrile-butadiene-styrene, bisphenol A polycarbonate, bisphenol fluorenone carbonatedimethylsiloxane block polymer, phenolphthalein-bisphenol A polycarbonate, phenolphthalein polycarbonate, polyether sulfone, polyphenylene oxide, polyphenylene sulfide, polyaryl sulfone, chlorinated polyvinyl chloride homopolymer, polyvinyl fluoride, and polyvinylidene fluoride. Processing parameters including molding characteristics of some of the advanced polymers are described. Test results and relative rankings of some of the flammability, smoke and toxicity properties are presented.

  2. Rapid discrimination of slimming capsules based on illegal additives by electronic nose and flash gas chromatography.

    PubMed

    Xia, Zhenzhen; Cai, Wensheng; Shao, Xueguang

    2015-02-01

    The discrimination of counterfeit and/or illegally manufactured medicines is an important task in the pharmaceutical industry for pharmaceutical safety. In this study, 22 slimming capsule samples with illegally added sibutramine and phenolphthalein were analyzed by electronic nose and flash gas chromatography. To reveal the difference among the different classes of samples, principal component analysis and linear discriminant analysis were employed to analyze the data acquired from electronic nose and flash gas chromatography, respectively. The samples without illegal additives can be discriminated from the ones with illegal additives by using electronic nose or flash gas chromatography data individually. To improve the performance of classification, a data fusion strategy was applied to integrate the data from electronic nose and flash gas chromatography data into a single model. The results show that the samples with phenolphthalein, sibutramine and both can be classified well by using fused data.

  3. Thermoplastic polymers for improved fire safety

    NASA Technical Reports Server (NTRS)

    Kourtides, D. A.; Parker, J. A.; Hilado, C. J.

    1976-01-01

    The thermochemical and flammability characteristics of some typical thermoplastic materials currently in use and others being considered for use in aircraft interiors are described. The properties studied included (1) thermomechanical properties such as glass transition and melt temperature, (2) changes in polymer enthalpy by differential scanning calorimetry, (3) thermogravimetric analysis in anaerobic and oxidative environments, (4) oxygen index, (5) smoke evolution, (6) relative toxicity of the volatile products of pyrolysis, and (7) selected physical properties. The generic polymers that were evaluated included: acrylonitrile butadiene styrene, bisphenol A polycarbonate, 9,9 bis (4-hydroxyphenyl) fluorene polycarbonatepoly (dimethyl siloxane) block polymer, phenolphthalein bisphenol A polycarbonate, phenolphthalein polycarbonate, polyether sulfone, polyphenylene oxide, polyphenylene sulfide, polyaryl sulfone, chlorinated polyvinyl chloride homopolymer, polyvinyl fluoride, and polyvinylidene fluoride. Processing parameters, including molding characteristics of some of the advanced polymers, are described. Test results and relative ranking of some of the flammability, smoke, and toxicity properties are presented.

  4. Depletion of hepatic uridine diphosphoglucuronic acid decreases the biliary excretion of drugs.

    PubMed

    Gregus, Z; Watkins, J B; Thompson, T N; Klaassen, C D

    1983-05-01

    Hepatic levels of uridine diphosphoglucuronic acid (UDPGA) in rats decreased substantially (greater than 80%) 40 min after galactosamine (GAL) (600 mg/kg i.p.) or after 1 hr of diethyl ether (DE) narcosis. Biliary excretion of several cholephils requiring glucuronidation before excretion was reduced by GAL 76, 62, 92, 90 and 97% for bilirubin, diethylstilbestrol, iopanoic acid, phenolphthalein and valproic acid, respectively. GAL treatment caused delayed plasma clearances of the parent compounds and reductions in plasma concentrations and biliary excretions of glucuronide conjugates. The degree of this reduction was related to the maximal excretion rate of the individual compounds. For phenolphthalein glucuronide and phenol-3,6-dibromphthalein disulfonate, which do not undergo conjugation, GAL had no effect on their biliary excretion. DE-induced UDPGA depletion had no effect on phenolphthalein glucuronide excretion but reduced that of phenol-3,6-dibromphthalein disulfonate 25%. DE did not affect the plasma elimination or biliary secretion of phenolphthalein. Of the other cholephils requiring conjugation, DE reduced the excretion of bilirubin, diethylstilbestrol, iopanoic acid and valproic acid by 41, 29, 76 and 28%, respectively. DE decreased the plasma elimination of the parent compounds and the appearance of the conjugates in both plasma and bile. Reduction of glucuronide excretion into bile was less pronounced at higher doses of the cholephilic anions. Neither treatment reduced in vitro hepatic UDP-glucuronosyltransferase activity toward these substrates or substantially altered extrahepatic UDPGA concentrations. Thus, both GAL and DE decreased UDPGA to similar concentrations, but the biliary excretion of compounds requiring glucuronidation before secretion was depressed to a greater extent by GAL.

  5. Proton NMR for detection, identification and quantification of adulterants in 160 herbal food supplements marketed for weight loss.

    PubMed

    Hachem, Rabab; Assemat, Gaëtan; Martins, Nathalie; Balayssac, Stéphane; Gilard, Véronique; Martino, Robert; Malet-Martino, Myriam

    2016-05-30

    One hundred and sixty food supplements (FS) marketed for weight loss and mainly purchased on the Internet were analyzed. All the FS were claimed as 100% natural containing only natural compounds, plant extracts and/or vitamins and the presence of an active pharmaceutical ingredient (API) was never mentioned. (1)H NMR spectroscopy was used for detecting the presence of adulterants and for their identification and quantification. Mass spectrometry was used as a complementary method for supporting their identification. Among the 164 samples considered because capsules from 5 different blisters of the same FS were analyzed, 56% were tainted with six API. Forty three contained sibutramine as single adulterant (26%), 9 phenolphthalein (6%) and 23 a mixture of these API (14%) that were both withdrawn from the market several years ago because of toxicity concerns. Sildenafil was found in 12 samples, either as a single adulterant (n=5) or in combination with sibutramine (n=3), phenolphthalein (n=3) and both sibutramine and phenolphthalein (n=1). Fluoxetine was present in 4 formulations, alone (n=3) or in combination with sibutramine and orlistat (n=1). At last, lorcaserine was detected in one FS. The content of sibutramine per dosage unit was comprised between 0.1 and 22 mg and that of phenolphthalein between 0.05 and 56 mg. The study also highlights poor manufacturing practices as evidenced for instance by the variability of API in capsules from different blisters of the same box. This paper demonstrates the need for more effective quality control of weight loss FS and the efficiency of (1)H NMR spectroscopy for the detection of tainted FS. PMID:26928212

  6. Carbonation and its effects in reinforced concrete

    SciTech Connect

    Broomfield, J.P.

    2000-01-01

    Carbonation is the result of interaction of carbon dioxide (CO{sub 2}) gas in the atmosphere with the alkaline hydroxides in the concrete. CO{sub 2} diffuses through the concrete and rate of movement of the carbonation front roughly follows Fick's law of diffusion. Carbonation depth can be measured by exposing fresh concrete and spraying it with phenolphthalein indicator solution. An example of the test on a reinforced concrete mullion is given.

  7. Active pharmaceutical ingredients detected in herbal food supplements for weight loss sampled on the Dutch market.

    PubMed

    Reeuwijk, Noortje M; Venhuis, Bastiaan J; de Kaste, Dries; Hoogenboom, Ron L A P; Rietjens, Ivonne M C M; Martena, Martijn J

    2014-01-01

    Herbal food supplements claiming to reduce weight may contain active pharmacological ingredients (APIs) that can be used for the treatment of overweight and obesity. The aim of this study was to determine whether herbal food supplements for weight loss on the Dutch market contain APIs with weight loss properties. Herbal food supplements intended for weight loss (n = 50) were sampled from August 2004 to May 2013. An HPLC-DAD-MS/MS method was used to screen for the presence of the APIs in herbal supplements. In 24 samples the APIs sibutramine, desmethylsibutramine (DMS), didesmethylsibutramine (DDMS), rimonabant, sildenafil and/or the laxative phenolphthalein were identified 41 times. The presence of these APIs was, however, not stated on the label. The potential pharmacological effects of the detected APIs were estimated using data from reported effective doses of approved drugs. Use of 20 of the 24 herbal food supplements may result in potential pharmacological effects. Furthermore, risk assessment of phenolphthalein, a suspected carcinogen and found to be present in 10 supplements, based on the margin of exposure (MOE) approach, resulted in MOE values of 96-30,000. MOE values lower than 10,000 (96-220) were calculated for the daily intake levels of four out of these 10 supplements in which phenolphthalein was found. However, taking into account that weight loss preparations may be used for only a few weeks or months rather than during a lifetime, MOE values may be two to three orders of magnitude higher. The current study shows that the use of food supplements with sibutramine, DMS, DDMS and/or phenolphthalein could result in pharmacological effects.

  8. Proton NMR for detection, identification and quantification of adulterants in 160 herbal food supplements marketed for weight loss.

    PubMed

    Hachem, Rabab; Assemat, Gaëtan; Martins, Nathalie; Balayssac, Stéphane; Gilard, Véronique; Martino, Robert; Malet-Martino, Myriam

    2016-05-30

    One hundred and sixty food supplements (FS) marketed for weight loss and mainly purchased on the Internet were analyzed. All the FS were claimed as 100% natural containing only natural compounds, plant extracts and/or vitamins and the presence of an active pharmaceutical ingredient (API) was never mentioned. (1)H NMR spectroscopy was used for detecting the presence of adulterants and for their identification and quantification. Mass spectrometry was used as a complementary method for supporting their identification. Among the 164 samples considered because capsules from 5 different blisters of the same FS were analyzed, 56% were tainted with six API. Forty three contained sibutramine as single adulterant (26%), 9 phenolphthalein (6%) and 23 a mixture of these API (14%) that were both withdrawn from the market several years ago because of toxicity concerns. Sildenafil was found in 12 samples, either as a single adulterant (n=5) or in combination with sibutramine (n=3), phenolphthalein (n=3) and both sibutramine and phenolphthalein (n=1). Fluoxetine was present in 4 formulations, alone (n=3) or in combination with sibutramine and orlistat (n=1). At last, lorcaserine was detected in one FS. The content of sibutramine per dosage unit was comprised between 0.1 and 22 mg and that of phenolphthalein between 0.05 and 56 mg. The study also highlights poor manufacturing practices as evidenced for instance by the variability of API in capsules from different blisters of the same box. This paper demonstrates the need for more effective quality control of weight loss FS and the efficiency of (1)H NMR spectroscopy for the detection of tainted FS.

  9. The relative fire resistance of select thermoplastic materials. [for aircraft interiors

    NASA Technical Reports Server (NTRS)

    Kourtides, D. A.; Parker, J. A.

    1978-01-01

    The relative thermal stability, flammability, and related thermochemical properties of some thermoplastic materials currently used in aircraft interiors as well as of some candidate thermoplastics were investigated. Currently used materials that were evaluated include acrylonitrile butadiene styrene, bisphenol A polycarbonate, polyphenylene oxide, and polyvinyl fluoride. Candidate thermoplastic materials evaluated include: 9,9-bis(4-hydroxyphenyl)fluorene polycarbonate-poly(dimethylsiloxane) block polymer, chlorinated polyvinylchloride homopolymer, phenolphthalein polycarbonate, polyethersulfone, polyphenylene sulfide, polyarylsulfone, and polyvinylidene fluoride.

  10. Nanocontainer-based corrosion sensing coating.

    PubMed

    Maia, F; Tedim, J; Bastos, A C; Ferreira, M G S; Zheludkevich, M L

    2013-10-18

    The present paper reports on the development of new sensing active coating on the basis of nanocontainers containing pH-indicating agent. The coating is able to detect active corrosion processes on different metallic substrates. The corrosion detection functionality based on the local colour change in active cathodic zones results from the interaction of hydroxide ions with phenolphthalein encapsulated in mesoporous nanocontainers which function as sensing nanoreactors. The mesoporous silica nanocontainers are synthesized and loaded with pH indicator phenolphthalein in a one-stage process. The resulting system is mesoporous, which together with bulkiness of the indicator molecules limits their leaching. At the same time, penetration of water molecules and ions inside the container is still possible, allowing encapsulated phenolphthalein to be sensitive to the pH in the surrounding environment and outperforming systems when an indicator is directly dispersed in the coating layer.The performed tests demonstrate the pH sensitivity of the developed nanocontainers being dispersed in aqueous solutions. The corrosion sensing functionality of the protective coatings with nanocontainers are proven for aluminium- and magnesium-based metallic substrates. As a result, the developed nanocontainers show high potential to be used in a new generation of active protective coatings with corrosion-sensing coatings.

  11. Phenolphthalein—Pink Tornado Demonstration

    NASA Astrophysics Data System (ADS)

    Prall, Bruce R.

    2008-04-01

    The phenolphthalein-pink tornado demonstration utilizes the vortex generated by a spinning magnetic stirring bar in a 1 L graduated cylinder containing 0.01 M HCl to demonstrate Le Châtelier's principle as it applies to the phenolphthalein equilibrium in water H 2 In + 2H 2 O 2H 2 O + + In 2 - where H 2 In is phenophthalein. The addition of 3-4 drops of phenolphthalein indicator solution followed immediately by 3-4 drops of 50% (w/w) NaOH to the vortex of the HCl solution results in a shift to the right in the equilibrium owing to the reaction of OH - + H 3 O + to form water. This shift is accompanied by the vortex becoming visible by the appearance of a pinkish-red color caused by an increase in In 2- concentration within the localized region of the vortex. The demonstration also provides one an excellent opportunity to discuss the topics of limiting reagent and reagent in excess. Some insight regarding the extent to which uniform mixing is achieved when using a magnetic stirrer is also provided. Included is a note from the Feature Editor, Ed Vitz.

  12. Chemical test for mammalian feces in grain products: collaborative study.

    PubMed

    Gerber, H R

    1989-01-01

    A collaborative study was conducted to validate the use of the AOAC alkaline phosphatase method for mammalian feces in corn meal, 44.B01-44.B06, for 7 additional products: brown rice cream, oat bran, grits, semolina, pasta flour, farina, and barley plus (a mixture of barley, oat bran, and brown rice). The proposed method determines the presence of alkaline phosphatase, an enzyme contained in mammalian feces, by using phenolphthalein diphosphate as the enzyme substrate in a test agar medium. Fecal matter is separated from the grain products by specific gravity differences in 1% test agar. As the product is distributed on liquid test agar, fecal fragments float while the grain products sink. The alkaline phosphatase cleaves phosphate radicals from phenolphthalein diphosphate, generating free phenolphthalein, which produces a pink to red-purple color around the fecal particles in the previously colorless medium. Collaborators' recovery averages ranged from 21.7 particles (72.3%) for oat bran to 25.3 particles (84.3%) for semolina at the 30 particle spike level. Overall average background was 0.4 positive reactions per food type. The collaborators reported that the method was quick, simple, and easy to use. The method has been approved interim official first action for all 7 grain products. PMID:2808238

  13. Acid-base titrations using microfluidic paper-based analytical devices.

    PubMed

    Karita, Shingo; Kaneta, Takashi

    2014-12-16

    Rapid and simple acid-base titration was accomplished using a novel microfluidic paper-based analytical device (μPAD). The μPAD was fabricated by wax printing and consisted of ten reservoirs for reaction and detection. The reaction reservoirs contained various amounts of a primary standard substance, potassium hydrogen phthalate (KHPth), whereas a constant amount of phenolphthalein was added to all the detection reservoirs. A sample solution containing NaOH was dropped onto the center of the μPAD and was allowed to spread to the reaction reservoirs where the KHPth neutralized it. When the amount of NaOH exceeded that of the KHPth in the reaction reservoirs, unneutralized hydroxide ion penetrated the detection reservoirs, resulting in a color reaction from the phenolphthalein. Therefore, the number of the detection reservoirs with no color change determined the concentration of the NaOH in the sample solution. The titration was completed within 1 min by visually determining the end point, which required neither instrumentation nor software. The volumes of the KHPth and phenolphthalein solutions added to the corresponding reservoirs were optimized to obtain reproducible and accurate results for the concentration of NaOH. The μPADs determined the concentration of NaOH at orders of magnitude ranging from 0.01 to 1 M. An acid sample, HCl, was also determined using Na2CO3 as a primary standard substance instead of KHPth. Furthermore, the μPAD was applicable to the titrations of nitric acid, sulfuric acid, acetic acid, and ammonia solutions. The μPADs were stable for more than 1 month when stored in darkness at room temperature, although this was reduced to only 5 days under daylight conditions. The analysis of acidic hot spring water was also demonstrated in the field using the μPAD, and the results agreed well with those obtained by classic acid-base titration.

  14. An improved method for analysis of hydroxide and carbonate in alkaline electrolytes containing zinc

    NASA Technical Reports Server (NTRS)

    Reid, M. A.

    1978-01-01

    A simplified method for titration of carbonate and hydroxide in alkaline battery electrolyte is presented involving a saturated KSCN solution as a complexing agent for zinc. Both hydroxide and carbonate can be determined in one titration, and the complexing reagent is readily prepared. Since the pH at the end point is shifted from 8.3 to 7.9-8.0, m-cresol purple or phenol red are used as indicators rather than phenolphthalein. Bromcresol green is recommended for determination of the second end point of a pH of 4.3 to 4.4.

  15. An improved method for analysis of hydroxide and carbonate in alkaline electrolytes containing zinc

    NASA Technical Reports Server (NTRS)

    Reid, M. A.

    1978-01-01

    A simplified method for titration of carbonate and hydroxide in alkaline battery electrolyte is presented involving a saturated KSCN solution as a complexing agent for zinc. Both hydroxide and carbonate can be determined in one titration, and the complexing reagent is readily prepared. Since the pH at the end point is shifted from 8.3 to 7.9 - 8.0, m-cresol purple or phenol red are used as indicators rather than phenolphthalein. Bromcresol green is recommended for determination of the second end point of a pH of 4.3 to 4.4.

  16. Study of thermal stability and degradation of fire resistant candidate polymers for aircraft interiors

    NASA Technical Reports Server (NTRS)

    Hsu, M. T. S.

    1976-01-01

    The thermochemistry of bismaleimide resins and phenolphthalein polycarbonate was studied. Both materials are fire-resistant polymers and may be suitable for aircraft interiors. The chemical composition of the polymers has been determined by nuclear magnetic resonance and infrared spectroscopy and by elemental analysis. Thermal properties of these polymers have been characterized by thermogravimetric analyses. Qualitative evaluation of the volatile products formed in pyrolysis under oxidative and non-oxidative conditions has been made using infrared spectrometry. The residues after pyrolysis were analyzed by elemental analysis. The thermal stability of composite panel and thermoplastic materials for aircraft interiors was studied by thermogravimetric analyses.

  17. Thermochemical characterization of some thermoplastic materials. [flammability and toxicity properties for aircraft interiors

    NASA Technical Reports Server (NTRS)

    Kourtides, D. A.; Parker, J. A.; Hilado, C. J.

    1977-01-01

    The thermochemical and flammability characteristics of some typical thermoplastic materials currently in use or being considered for use in aircraft interiors are described. The properties studied included thermomechanical properties such as glass-transition and melt temperature, changes in polymer enthalpy, thermogravimetric analysis in anerobic and oxidative environments, oxygen index, smoke evolution, relative toxicity of the volatile products of pyrolysis, and selected physical properties. The generic polymers evaluated included acrylonitrile butadiene styrene, bisphenol A polycarbonate, 9,9 bis (4-hydroxyphenyl) fluorene polycarbonate-poly (dimethylsiloxane) block polymer, phenolphthalein-bisphenol A polycarbonate, phenolphthalein polycarbonate, polyether sulfone, polyphenylene oxide, polyphenylene sulfide, polyaryl sulfone, chlorinated polyvinyl chloride homopolymer, polyvinyl fluoride, and polyvinylidene fluoride. Processing parameters, including molding characteristics of some of the advanced polymers, are described. Test results and relative rankings of some of the flammability, smoke, and toxicity properties are presented. Under these test conditions, some of the advanced polymers evaluated were significantly less flammable and toxic than or equivalent to polymers in current use.

  18. Active oxygen doctors the evidence

    NASA Astrophysics Data System (ADS)

    Castelló, Ana; Francès, Francesc; Corella, Dolores; Verdú, Fernando

    2009-02-01

    Investigation at the scene of a crime begins with the search for clues. In the case of bloodstains, the most frequently used reagents are luminol and reduced phenolphthalein (or phenolphthalin that is also known as the Kastle-Meyer colour test). The limitations of these reagents have been studied and are well known. Household cleaning products have evolved with the times, and new products with active oxygen are currently widely used, as they are considered to be highly efficient at removing all kinds of stains on a wide range of surfaces. In this study, we investigated the possible effects of these new cleaning products on latent bloodstains that may be left at a scene of a crime. To do so, various fabrics were stained with blood and then washed using cleaning agents containing active oxygen. The results of reduced phenolphthalein, luminol and human haemoglobin tests on the washed fabrics were negative. The conclusion is that these new products alter blood to such an extent that it can no longer be detected by currently accepted methods employed in criminal investigations. This inability to locate bloodstains means that highly important evidence (e.g. a DNA profile) may be lost. Consequently, it is important that investigators are aware of this problem so as to compensate for it.

  19. Development and the Educational Effect of a System of the Corrosion of Iron and the Anti-corrosion Ability of Conductive Polymer Polyaniline

    NASA Astrophysics Data System (ADS)

    Yano, Jun; Nakamura, Noriyuki; Yamazaki, Suzuko; Ichimori, Hayato; Osaki, Nobukazu; Okano, Hiroshi

    Few general chemistry textbooks of high schools, colleges and universities introduce the corrosion of iron into the oxidation-reduction (redox) section, although the corrosion is very popular phenomena for students. Besides, no description appears about conductive polymers as anti-corrosion materials. The corrosion is a redox reaction proceeding through the local cell mechanism : the iron oxidation half-cell reaction at the local anode and the reduction of oxygen at the local cathode. To prepare a teaching tool for understanding of the mechanism, the visualization of the corrosion was attempted using phenolphthalein and potassium hexacyanoferrate (III) as color couplers for the anodic and cathodic products : Fe2+ and OH-. The local anode and cathode were obviously shown as gradual blue and red coloration when commercial nails were soaked in 4% NaCl aqueous solution containing phenolphthalein and potassium hexacyanoferrate (III) . On the other hand, no coloration occurred for the nail covered with a conductive polymer polyaniline. To know the anti-corrosion mechanism, the open-circuit potential of the nail was measured. The fact that the potential was kept at the potential range where iron was passivated implied that polyaniline acted as an in-situ oxidant. The visualization was experimentally performed at an actual chemistry class and the utility value was estimated. As a result, the visualization is expected to be a useful teaching tool for the corrosion and the understanding of the role of polyaniline as the anti-corrosion material.

  20. Determination of Chlorinity of Water without the Use of Chromate Indicator

    PubMed Central

    Hong, Tae-Kee; Kim, Myung-Hoon; Czae, Myung-Zoon

    2010-01-01

    A new method for determining chlorinity of water was developed in order to improve the old method by alleviating the environmental problems associated with the toxic chromate. The method utilizes a mediator, a weak acid that can form an insoluble salt with the titrant. The mediator triggers a sudden change in pH at an equivalence point in a titration. Thus, the equivalence point can be determined either potentiometrically (using a pH meter) or simply with an acid-base indicator. Three nontoxic mediators (phosphate, EDTA, and sulfite) were tested, and optimal conditions for the sharpest pH changes were sought. A combination of phosphate (a mediator) and phenolphthalein (an indicator) was found to be the most successful. The choices of the initial pH and the concentration of the mediator are critical in this approach. The optimum concentration of the mediator is ca. 1~2 mM, and the optimum value of the initial pH is ca. 9 for phosphate/phenolphthalein system. The method was applied to a sample of sea water, and the results are compared with those from the conventional Mohr-Knudsen method. The new method yielded chlorinity of a sample of sea water of (17.58 ± 0.22) g/kg, which is about 2.5% higher than the value (17.12 ± 0.22) g/kg from the old method. PMID:21461358

  1. The experimental investigation of concrete carbonation depth

    SciTech Connect

    Chang, C.-F. . E-mail: s83808@yahoo.com.tw; Chen, J.-W.

    2006-09-15

    Phenolphthalein indicator has traditionally been used to determine the depth of carbonation in concrete. This investigation uses the thermalgravimetric analysis (TGA) method, which tests the concentration distribution of Ca(OH){sub 2} and CaCO{sub 3}, while the X-ray diffraction analysis (XRDA) tests the intensity distribution of Ca(OH){sub 2} and CaCO{sub 3}. The Fourier transformation infrared spectroscopy (FTIR) test method detects the presence of C-O in concrete samples as a basis for determining the presence of CaCO{sub 3}. Concrete specimens were prepared and subjected to accelerated carbonation under conditions of 23 deg. C temperature, 70% RH and 20% concentration of CO{sub 2}. The test results of TGA and XRDA indicate that there exist a sharp carbonation front. Three zones of carbonation were identified according to the degree of carbonation and pH in the pore solutions. The TGA, XRDA and FTIR results showed the depth of carbonation front is twice of that determined from phenolphthalein indicator.

  2. Structure-Based Discovery of Inhibitors of Thymidylate Synthase

    NASA Astrophysics Data System (ADS)

    Shoichet, Brian K.; Stroud, Robert M.; Santi, Daniel V.; Kuntz, Irwin D.; Perry, Kathy M.

    1993-03-01

    A molecular docking computer program (DOCK) was used to screen the Fine Chemical Directory, a database of commercially available compounds, for molecules that are complementary to thymidylate synthase (TS), a chemotherapeutic target. Besides retrieving the substrate and several known inhibitors, DOCK proposed putative inhibitors previously unknown to bind to the enzyme. Three of these compounds inhibited Lactobacillus caser TS at submillimolar concentrations. One of these inhibitors, sulisobenzone, crystallized with TS in two configurations that differed from the DOCK-favored geometry: a counterion was bound in the substrate site, which resulted in a 6 to 9 angstrom displacement of the inhibitor. The structure of the complexes suggested another binding region in the active site that could be exploited. This region was probed with molecules sterically similar to sulisobenzone, which led to the identification of a family of phenolphthalein analogs that inhibit TS in the 1 to 30 micromolar range. These inhibitors do not resemble the substrates of the enzyme. A crystal structure of phenolphthalein with TS shows that it binds in the target site in a configuration that resembles the one suggested by DOCK.

  3. Qualitative screening for adulterants in weight-loss supplements by ion mobility spectrometry.

    PubMed

    Dunn, Jamie D; Gryniewicz-Ruzicka, Connie M; Mans, Daniel J; Mecker-Pogue, Laura C; Kauffman, John F; Westenberger, Benjamin J; Buhse, Lucinda F

    2012-12-01

    Ion mobility spectrometry (IMS) served as a rapid, qualitative screening tool for the analysis of adulterated weight-loss products. We have previously shown that sibutramine extracted into methanol from dietary supplements can be detected at low levels (2ng) using a portable IMS spectrometer, and have adapted a similar method for the analysis of additional weight-loss product adulterants. An FDA collaborative study helped to define the limits for fluoxetine with a limit of detection of 2ng. We also evaluated more readily available, less toxic extraction solvents and found isopropanol and water were comparable to methanol. Isopropanol was favored over water for two reasons: (1) water increases the analysis time and (2) aqueous solutions were more susceptible to pH change, which affected the detection of sibutramine. In addition to sibutamine and fluoxetine, we surveyed 11 weight-loss adulterants; bumetanide, fenfluramine, furosemide, orlistat, phenolphthalein, phentermine, phenytoin, rimonabant, sertraline and two sibutramine analogs, desmethylsibutramine and didesmethylsibutramine, using portable and benchtop ion mobility spectrometers. Out of these 13 active pharmaceutical ingredients (APIs), portable and benchtop ion mobility spectrometers were capable of screening products for 10 of these APIs. The developed procedure was applied to two weight-loss dietary supplements using both portable and benchtop instruments. One product contained didesmethylsibutramine while the other contained didesmethylsibutramine and phenolphthalein. PMID:22902504

  4. Enhanced performance of anion exchange membranes via crosslinking of ion cluster regions for fuel cells

    NASA Astrophysics Data System (ADS)

    Lai, Ao Nan; Guo, Dong; Lin, Chen Xiao; Zhang, Qiu Gen; Zhu, Ai Mei; Ye, Mei Ling; Liu, Qing Lin

    2016-09-01

    Development of anion exchange membranes (AEMs) with high hydroxide conductivity, good dimensional and alkaline stabilities is still a challenge for the practical application of AEM fuel cells. In this study, we report a new strategy to prepare high-performance AEMs with crosslinked ionic regions. A series of phenolphthalein-containing poly(arylene ether sulfone)s crosslinked AEMs was synthesized by grafting ion groups selectively and densely on the phenolphthalein units to form ion clusters that are further crosslinked to generate the hydrophilic ionic regions. The crosslinking reaction not only improved the dimensional stability of the AEMs, but also increased the aggregation of the ion clusters leading to the formation of hydrophilic/hydrophobic phase-separated morphology and ion-conducting channels. As a result, enhancements in both ion conductivity and dimensional stability can be achieved. The crosslinked AEMs showed high hydroxide conductivities in the range of 52.2-143.4 mS cm-1 from 30 to 80 °C and a superb ratio of relative conductivity to relative swelling at 80 °C. Furthermore, the crosslinked AEMs also exhibited good mechanical properties, thermal and alkaline stabilities and desirable single cell performance. This work presents a promising strategy for the synthesis of high-performance AEMs for fuel cells.

  5. Alteration of expirated bloodstain patterns by Calliphora vicina and Lucilia sericata (Diptera: Calliphoridae) through ingestion and deposition of artifacts.

    PubMed

    Striman, Becca; Fujikawa, Amanda; Barksdale, Larry; Carter, David O

    2011-01-01

    Bloodstain pattern analysis can provide insight into a sequence of events associated with a violent crime. However, bloodstain pattern analysis can be confounded by the feeding activity of blow flies. We conducted two laboratory experiments to investigate the relationships between Lucilia sericata (green bottle fly) and Calliphora vicina (blue bottle fly), expirated bloodstains, and pooled bloodstains on a range of surfaces (linoleum, wallpaper, textured paint). C. vicina and L. sericata changed bloodstain pattern morphology through feeding and defecation. They also deposited artifacts in rooms where blood was not present originally. Chemical presumptive tests (Hemastix(®) , phenolphthalein, leucocrystal violet, fluorescein) were not able to differentiate between insect artifacts and bloodstains. Thus, C. vicina and L. sericata can confound bloodstain pattern analysis, crime scene investigation, and reconstruction. Crime scene investigators should be aware of these fundamental behaviors, and the effects that blow flies can have on expirated and pooled bloodstain patterns. PMID:21039518

  6. What Is the Opposite of Pandora’s Box? Direct Analysis, Ambient Ionization, and a New Generation of Atmospheric Pressure Ion Sources

    PubMed Central

    B. Cody, Robert

    2013-01-01

    The introduction of DART and DESI sources approximately seven years ago led to the development of a new series of atmospheric pressure ion sources referred to as “ambient ionization” sources. These fall into two major categories: spray techniques like DESI or plasma techniques like DART. The selectivity of “direct ionization,” meaning analysis without chromatography and with little or no sample preparation, depends on the mass spectrometer selectivity. Although high resolution and tandem mass spectrometry are valuable tools, rapid and simple sample preparation methods can improve the utility of ambient ionization methods. The concept of ambient ionization has led to the realization that there are many more ways to form ions than might be expected. An interesting example is the use of a flint-and-steel spark source to generate ions from compounds such as phenolphthalein and Gramicidin S. PMID:24349926

  7. A comparison of the presumptive luminol test for blood with four non-chemiluminescent forensic techniques.

    PubMed

    Webb, Joanne L; Creamer, Jonathan I; Quickenden, Terence I

    2006-01-01

    Presumptive blood detection tests are used by forensic investigators to detect trace amounts of blood or to investigate suspicious stains. Through the years, a number of articles have been published on the popular techniques of the day. However, there is no single paper that critiques and compares the five most common presumptive blood detection tests currently in use: luminol, phenolphthalein (Kastle-Meyer), leucomalachite green, Hemastix and the forensic light source. The present authors aimed to compare the above techniques with regard to their sensitivity, ease of use and safety. The luminol test was determined to be the most sensitive of the techniques, while Hemastix is a suitable alternative when the luminol test is not appropriate.

  8. The osmotic stability of lysosomes from adult and foetal guinea-pig liver tissue.

    PubMed

    Turnbull, J M; Neil, M W

    1969-02-01

    1. Lysosome-rich fractions were obtained from foetal liver tissues as early as 35 days uterine age. Foetal lysosomes showed the same ;structure-linked latency' and acid hydrolytic potentiality characteristic of their adult counterparts. 2. The osmotic stability of lysosome-rich fraction from foetal guinea-pig liver tissue was greater than that of the corresponding adult lysosome fractions, p-nitrophenyl-phosphatase being used as marker enzyme. 3. The observation was confirmed by using beta-glycerophosphatase and phenolphthalein beta-glucuronidase as alternative marker enzymes. p-Nitrophenyl phosphate and beta-glycerophosphate appear to act as substrates for the same enzyme. 4. By using p-nitrophenylphosphatase activity measurements it was shown that the osmotic stability of foetal lysosomal fractions decreased with increasing foetal age, but at no time achieved the degree of osmotic instability characteristic of adult lysosomal fractions. 5. The correlation of these findings with the intracellular environment of lysosomes is discussed.

  9. Dynamic behavior of iron forms in rapid reduction of carbon-coated iron ore

    SciTech Connect

    Sugawara, Katsuyasu; Morimoto, Koji; Sugawara, T.; Dranoff, J.S.

    1999-03-01

    As a part of a fundamental study of the kinetics of rapid smelting reduction of iron oxide with solid carbon, particles of carbon-coated iron ore were prepared by heating a mixture of iron ore and phenolphthalein (a model compound of coal tar) at 773 K in a nitrogen stream. The reduction behavior of the carbon-coated iron ore particles during rapid heating was studied using a drop-tube reactor at temperatures from 1,073 to 1,773 K. The reduction extent increased rapidly with the beginning of melting at temperatures over 1,650 K, reaching 60% at 1,773 within 0.7 s. The observed changes in the distribution of iron states in the particles were successfully simulated.

  10. Approaches to flame resistant polymeric materials

    NASA Technical Reports Server (NTRS)

    Liepins, R.

    1975-01-01

    Four research and development areas are considered for further exploration in the quest of more flame-resistant polymeric materials. It is suggested that improvements in phenolphthalein polycarbonate processability may be gained through linear free energy relationship correlations. Looped functionality in the backbone of a polymer leads to both improved thermal resistance and increased solubility. The guidelines used in the pyrolytic carbon production constitute a good starting point for the development of improved flame-resistant materials. Numerous organic reactions requiring high temperatures and the techniques of protected functionality and latent functionality constitute the third area for exploration. Finally, some well-known organic reactions are suggested for the formation of polymers that were not made before.

  11. An automatic system for acidity determination based on sequential injection titration and the monosegmented flow approach.

    PubMed

    Kozak, Joanna; Wójtowicz, Marzena; Gawenda, Nadzieja; Kościelniak, Paweł

    2011-06-15

    An automatic sequential injection system, combining monosegmented flow analysis, sequential injection analysis and sequential injection titration is proposed for acidity determination. The system enables controllable sample dilution and generation of standards of required concentration in a monosegmented sequential injection manner, sequential injection titration of the prepared solutions, data collecting, and handling. It has been tested on spectrophotometric determination of acetic, citric and phosphoric acids with sodium hydroxide used as a titrant and phenolphthalein or thymolphthalein (in the case of phosphoric acid determination) as indicators. Accuracy better than |4.4|% (RE) and repeatability better than 2.9% (RSD) have been obtained. It has been applied to the determination of total acidity in vinegars and various soft drinks. The system provides low sample (less than 0.3 mL) consumption. On average, analysis of a sample takes several minutes. PMID:21641455

  12. What Is the Opposite of Pandora's Box? Direct Analysis, Ambient Ionization, and a New Generation of Atmospheric Pressure Ion Sources.

    PubMed

    B Cody, Robert

    2013-01-01

    The introduction of DART and DESI sources approximately seven years ago led to the development of a new series of atmospheric pressure ion sources referred to as "ambient ionization" sources. These fall into two major categories: spray techniques like DESI or plasma techniques like DART. The selectivity of "direct ionization," meaning analysis without chromatography and with little or no sample preparation, depends on the mass spectrometer selectivity. Although high resolution and tandem mass spectrometry are valuable tools, rapid and simple sample preparation methods can improve the utility of ambient ionization methods. The concept of ambient ionization has led to the realization that there are many more ways to form ions than might be expected. An interesting example is the use of a flint-and-steel spark source to generate ions from compounds such as phenolphthalein and Gramicidin S. PMID:24349926

  13. Sequestration of CO2 by concrete carbonation.

    PubMed

    Galan, Isabel; Andrade, Carmen; Mora, Pedro; Sanjuan, Miguel A

    2010-04-15

    Carbonation of reinforced concrete is one of the causes of corrosion, but it is also a way to sequester CO2. The characteristics of the concrete cover should ensure alkaline protection for the steel bars but should also be able to combine CO2 to a certain depth. This work attempts to advance the knowledge of the carbon footprint of cement. As it is one of the most commonly used materials worldwide, it is very important to assess its impact on the environment. In order to quantify the capacity of cement based materials to combine CO2 by means of the reaction with hydrated phases to produce calcium carbonate, Thermogravimetry and the phenolphthalein indicator have been used to characterize several cement pastes and concretes exposed to different environments. The combined effect of the main variables involved in this process is discussed. The moisture content of the concrete seems to be the most influential parameter. PMID:20225850

  14. Flammability and Photo-Stability of Selected Polymer Systems

    NASA Technical Reports Server (NTRS)

    Lo, Jeelin

    1981-01-01

    A systematic approach to the improvement of the flammability of epoxy resins, bisphenol-A polycarbonate poly(butylene terephthalate), and Nylon 6.6 by introducing halogens and loop functionality into the flame retardants is described. The phthalides (the loop functionality containing molecules) include 3,3-bis(4-bromophenyl)-phthalide, 3,3-bis(4-chlorophenyl)phthalide, and phenolphthalein. The phthalide containing epoxy resins are synthesized and characterized in comparison with the bisphenol-A epoxy resins in terms of flammability in the copolymer systems. The resins include diglycidyl ethers of phenolphthalein, bisphenol-A. tetrabromobisphenol-A, and tetraoromophenolphthalein. The vaporization of the phthalide additive in the polymers is observed in Thermal Gravimetric Analysis. The flame retardancy is primarily due to the presence of halogens. In the poly(butylene terephthalate) system, the cleavage of the C(sub aromatic) -B bond of the flame retardant additive enhances the crosslinking react ions between the aromatic rings resulting in an increase of char formation. In the epoxy resin systems, loop functionality contributes to char formation to a larger extent. The interaction between the epoxy resin and poly-(butylene terephthalate) follows the mechanism of insertion of the oxirane ring into the ester bond. This mechanism is studied by FT-IR. The investigation of the thermal properties of the char-forming phenol-formaldehyde resins is conducted to provide information for the systematic design of high temperature flame-resistant phenolics. NMR and FT-IR are used to characterize the oligomeric resins and the cured resins. The curing agents used in the study include formaldehyde, s-trioxane and terephthaloyl chloride. The brominated phenolic resins are found to have higher oxygen indices with lower char yields.

  15. Electric charge-mediated coalescence of water droplets for biochemical microreactors

    PubMed Central

    Jung, Yong-Mi; Kang, In Seok

    2010-01-01

    This work proposes the use of charged droplets driven by the Coulombic force as solution-phase reaction chambers for biological microreactions. A droplet can be charged near an electrode under dc voltage by direct contact to the electrode. This process is called electrical charging of droplet (ECOD). This charged droplet can then be transported rapidly between electrodes following the arc of an electric field line by exploiting electrostatic force. As on-demand electrocoalescence, both alkalization of phenolphthalein and bioluminescence reaction of luciferase in the presence of adenosine triphosphate are studied to test the feasibility of the biochemical microreactors using ECOD. Two oppositely charged droplets are merged to have a color change immediately after microchemical reaction. The applicability of an ECOD-driven droplet to measurement of glucose concentration is also tested. The glucose concentration is measured using a colorimetric enzyme-kinetic method based on Trinder’s reaction [J. Clin. Pathol. 22, 158 (1969)]. The color change in the merged droplet is detected with an absorbance measurement system consisting of a photodiode and a light emitting diode. PMID:20697585

  16. Catching anions with coloured assemblies: binding of pH indicators by a giant-size polyammonium macrocycle for anion naked-eye recognition.

    PubMed

    Bartoli, Francesco; Bencini, Andrea; Conti, Luca; Giorgi, Claudia; Valtancoli, Barbara; Paoli, Paola; Rossi, Patrizia; Le Bris, Nathalie; Tripier, Raphael

    2016-09-21

    A giant-size polyamine macrocycle L, composed of four 1,4,8,11-tetraazacyclotetradecane (cyclam) units linked by 1,3-dimethylenbenzyl spacers, strongly interacts in aqueous solution with four pH indicators (bromocresol purple (H2BCP), phenol red (H2PR), phenolphthalein (H2PP) and fluorescein (H2F)) in their anionic forms. Besides 1 : 1 complexes, L also forms assemblies with an unusual 1 : 2 receptor to dye stoichiometry, thanks to its large dimensions, which allow for the simultaneous interaction of the receptor protonated forms with two anionic dyes. The formation of the assemblies markedly affects the pKa values of the phenol groups of the dyes, which change colour upon complexation in well-defined pH ranges. This property can be effectively exploited for optical detection of anions. The L-H2BCP 1 : 2 assembly is able to selectively detect the triphosphate anion at slightly acidic pH values, thanks to the release, upon triphosphate coordination, of the dye from the ensemble, with a consequent colour change of the solution from purple-violet (complexed BCP(2-) dye) to yellow (free BCP(2-)). No effect is caused by other inorganic anions. The L-H2BCP 1 : 2 assembly represents a rare case of an optical chemosensor for the triphosphate anion. PMID:27530722

  17. Effect of different carboxylic acids in cyclodextrin functionalization of cellulose nanocrystals for prolonged release of carvacrol.

    PubMed

    Castro, D O; Tabary, N; Martel, B; Gandini, A; Belgacem, N; Bras, J

    2016-12-01

    Current investigations deal with new surface functionalization strategy of nanocrystalline cellulose-based substrates to impart active molecule release properties. In this study, cellulose nanocrystals (CNC) were surface-functionalized with β-cyclodextrin (β-CD) using succinic acid (SA) and fumaric acid (FA) as bridging agents. The main objective of this surface modification performed only in aqueous media was to obtain new active materials able to release antibacterial molecules over a prolonged period of time. The reactions were conducted by immersing the CNC film into a solution composed of β-CD, SA and FA, leading to CNC grafting. The materials were characterized by infrared spectroscopy (FT-IR), Quartz crystal microbalance-dissipation (QCM-D), AFM and phenolphthalein (PhP) was used to determine the efficiency of CNC grafting with β-CD. The results indicated that β-CD was successfully attached to the CNC backbone through the formation of ester bonds. Furthermore, carvacrol was entrapped by the attached β-CD and a prolonged release was confirmed. In particular, CNC grafted to β-CD in the presence of FA was selected as the best solution. The antibacterial activity and the controlled release were studied for this sample. Considerably longer bacterial activity against B. subtilis was observed for CNC grafted to β-CD compared to CNC and CNC-FA, confirming the promising impact of the present strategy. PMID:27612798

  18. Bisphenols that stimulate cells to release alkali metal cations: a structure-activity study.

    PubMed

    Hopp, L; Megee, S O; Lloyd, J B

    1998-10-22

    The laxative action of phenolphthalein (5) is believed to result from induction of potassium and water efflux from the colon epithelium. In cultured cells, K+ efflux is promoted by 5 and by a contaminant (1) present in commercial phenol red. Six compounds with chemical structures related to those of 5 and 1 were tested for ability to induce the release of 86Rb from COS-7 cells preloaded with this isotope: 4,4'-(9-fluorenylidene)diphenol (2), 4, 4'-(9-fluorenylidene)dianiline, 4, 4'-(9-fluorenylidene)bisphenoxyethanol, 1,1'-bi-2-naphthol, 4, 4'-biphenol, and bis(4-hydroxyphenyl)methane. With one exception these compounds were all inactive at a concentration of 10 microM. However, 2 caused profound 86Rb efflux at concentrations as low as 100 nM. Concentrations of 5 1-2 orders of magnitude higher were needed to achieve similar levels of activity. The three compounds known to be active in this experimental system share a common feature that is absent in all the inactive compounds: a five-membered ring structure, one of whose carbon atoms is disubstituted with p-hydroxyphenyl residues. Because 2 and 5 are readily available, comparative studies on the mechanism of action of these biphenols at the cellular level can now be undertaken. PMID:9784117

  19. Carbonation and pH in mortars manufactured with supplementary cementitious materials

    SciTech Connect

    McPolin, D.O.; Basheer, P.A.M.; Long, A.E.

    2009-05-15

    An investigation of carbonation in mortars and methods of measuring the degree of carbonation and pH change is presented. The mortars were manufactured using ordinary portland cement, pulverized fuel ash, ground granulated blast-furnace slag, metakaolin, and microsilica. The mortars were exposed to a carbon dioxide-rich environment (5% CO{sub 2}) to accelerate carbonation. The resulting carbonation was measured using phenolphthalein indicator and thermogravimetric analysis. The pH of the pore fluid and a powdered sample, extracted from the mortar, was measured to give an accurate indication of the actual pH of the concrete. The pH of the extracted powder mortar sample was found to be similar to the pH of the pore fluid expressed from the mortars. The thermogravimetric analysis suggested two distinct regions of transport of CO{sub 2} within mortar, a surface region where convection was prevalent and a deeper region where diffusion was dominant. The use of microsilica has been shown to decrease the rate of carbonation, while pulverized fuel ash and ground granulated blast-furnace slag have a detrimental effect on carbonation. Metakaolin has little effect on carbonation.

  20. Design and characterization of a plastic optical fiber pH sensor

    NASA Astrophysics Data System (ADS)

    Ferreira, Licínio; Simões, Pedro; Carvalho, Rui S.; Lopes, Paulo; Ferreira, Mário

    2013-11-01

    In this paper are present the design and characterization of a pH sensor using plastic optical fiber (POF) technology and a material produced by the sol-gel process with TEOS (tetraethyl orthosilicate) to immobilize universal indicator of pH (comprised of Thymol Blue, Methyl Red, Bromothymol Blue and Phenolphthalein) inside the silica matrix. This matrix is positioned between two extensions of plastic optical fiber tightly positioned at each side with both fibers aligned and sharing a common optical axis. This set will work as a pH sensor since the matrix embedded with indicator and in the presence of a solution (basic or acid solution) will change the optical transmittance properties. The optical source is a superluminescent white LED and the receiver is a photodiode having a good and linear responsivity in the visible spectrum. This pH sensitive matrix has large pores which allow the diffusion of the surrounding fluid molecules into the matrix and thus the close contact of these to the indicator molecules. This contact causes the change of color of the whole matrix allowing proper colorimetric detection by the photodiode. This variation of color associated with the detector wavelength linear response is the base of operation of the proposed device. This pH sensor presents many advantages over the standard and commercial pH meters namely, lightweight, portability and a low cost.

  1. Tracer-monitored flow titrations.

    PubMed

    Sasaki, Milton K; Rocha, Diogo L; Rocha, Fábio R P; Zagatto, Elias A G

    2016-01-01

    The feasibility of implementing tracer-monitored titrations in a flow system is demonstrated. A dye tracer is used to estimate the instant sample and titrant volumetric fractions without the need for volume, mass or peak width measurements. The approach was applied to spectrophotometric flow titrations involving variations of sample and titrant flow-rates (i.e. triangle programmed technique) or concentration gradients established along the sample zone (i.e. flow injection system). Both strategies required simultaneous monitoring of two absorbing species, namely the titration indicator and the dye tracer. Mixing conditions were improved by placing a chamber with mechanical stirring in the analytical path aiming at to minimize diffusional effects. Unlike most of flow-based titrations, the innovation is considered as a true titration, as it does not require a calibration curve thus complying with IUPAC definition. As an application, acidity evaluation in vinegars involving titration with sodium hydroxide was selected. Phenolphthalein and brilliant blue FCF were used as indicator and dye tracer, respectively. Effects of sample volume, titrand/titrant concentrations and flow rates were investigated aiming at improved accuracy and precision. Results were reliable and in agreement with those obtained by a reference titration procedure.

  2. Effects of subacute treatment with cocaine on activities of n-demethylase, UDP-glucuronyltransferase and sulfotransferase in WKY and SHR rat liver - sex and strain differences

    SciTech Connect

    Watanabe, H.K.; Hoskins, B.; Ho, I.K.

    1988-01-01

    The effects of subacute treatment with cocaine on activities of cocaine N-demethylase, UDP-glucuronyltransferase (GT) toward 4-nitrophenol and phenolphthalein and sulfotransferase (ST) toward androsterone and 4-nitrophenol in livers from Wistar Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) were investigated. Hepatic metabolism of cocaine was different between the sexes (with males having higher N-demethylase activity) and the strains (with WKY rats having higher activity). The effects of subacute cocaine administration on the activity of cocaine N-demethylase were also sex- and strain-related. Whereas cocaine administration increased activity of hepatic N-demethylase in both female strains, it decreased activity in male WKY and had no effect on activity in male SHR. Sex and strain-related as well as cocaine-induced differences were also found in activities of hepatic GT toward 4-nitrophenol and phenolphtalein as well as in activity of hepatic ST towards andersterone and 4-nitrophenol. These results suggest that some of the individual variation in the effects of cocaine may be due to sex and genetic differences in the hepatic metabolism of cocaine and/or in sexually and/or genetically-determined differences in how cocaine affects hepatic metabolism of other xenobiotics. 20 references, 4 figures.

  3. An improved microfluidics approach for monitoring real-time interaction profiles of ultrafast molecular recognition

    NASA Astrophysics Data System (ADS)

    Batabyal, Subrata; Rakshit, Surajit; Kar, Shantimoy; Pal, Samir Kumar

    2012-04-01

    Our study illustrates the development of a microfluidics (MF) platform combining fluorescence microscopy and femtosecond/picosecond-resolved spectroscopy to investigate ultrafast chemical processes in liquid-phase diffusion-controlled reactions. By controlling the flow rates of two reactants in a specially designed MF chip, sub-100 ns time resolution for the exploration of chemical intermediates of the reaction in the MF channel has been achieved. Our system clearly rules out the possibility of formation of any intermediate reaction product in a so-called fast ionic reaction between sodium hydroxide and phenolphthalein, and reveals a microsecond time scale associated with the formation of the reaction product. We have also used the developed system for the investigation of intermediate states in the molecular recognition of various macromolecular self-assemblies (micelles) and genomic DNA by small organic ligands (Hoechst 33258 and ethidium bromide). We propose our MF-based system to be an alternative to the existing millisecond-resolved "stopped-flow" technique for a broad range of time-resolved (sub-100 ns to minutes) experiments on complex chemical/biological systems.

  4. Water quality of streams tributary to Lakes Superior and Michigan

    USGS Publications Warehouse

    Zimmerman, Jerome W.

    1968-01-01

    Water quality of streams tributary to Lakes Superior and Michigan was analyzed for 142 stations on 99 streams tributary to Lake Superior and 83 stations on 56 streams tributary to Lake Michigan during 1962-65. Concentrations of aluminum, copper, and iron were not affected greatly by flow or season. Magnesium, calcium, chlorides, total alkalinity, total hardness, and conductivity varied with the flow, temperature, and season; the lowest values were during the spring runoff and heavy rains, and the highest were during low water in late summer and the colder periods of winter. Concentrations of nitrate, silica, and sulfates were lowest in the spring and summer. Concentrations of tanninlike and ligninlike compounds were highest during the spring runoff and other high-water periods, and were lowest during freezeup when surface runoff was minimal. The pH values were highest from June to September and lowest during the spring runoff. Phenolphthalein alkalinity was detected primarily in the summer and coincided occasionally with low flows just before the spring thaw. Total hardness usually was lower in streams tributary to Lake Superior than in streams tributary to Lake Michigan. The total hardness was higher in the streams in Wisconsin than in the streams in Michigan along the west shore of Lake Michigan. It was lowest in the northernmost streams. The water quality of the streams in an area was related to the geological characteristics of the land.

  5. Preparation, characterization, and bacteriostasis of AgNP-coated β-CD grafting cellulose beads.

    PubMed

    Wang, Ting; Li, Bin; Lin, Li

    2013-03-01

    A novel functional material of β-cyclodextrin (β-CD) grafting cellulose beads containing immobilized silver nanoparticles (AgNPs) is presented in this paper. The morphology was characterized by scanning electron microscopy, energy-dispersive X-ray, and X-ray photoelectron spectroscopy. Phenolphthalein probe molecule technique was used to detect the activity of the grafting β-CD, and the results demonstrated that the deposition of AgNPs had no influence on its encapsulation ability. Acid resistance of the AgNPs on the bead material was studied by atomic absorption spectrometry. The stability of the AgNPs was enhanced due to the grafting of β-CD. Tube dilution method was applied to study the bacteriostatic effect, and the minimal inhibitory doses of the novel material against Escherichia coli and Staphylococcus aureus were 12.5 and 25 mg, respectively. The minimal bactericidal doses for the two bacteria were 25 and 25 mg, respectively. PMID:23340866

  6. Solvothermal synthesis of V{sub 4}O{sub 9} flake-like morphology and its photocatalytic application in the degradation of methylene blue

    SciTech Connect

    Chine, M.K.; Sediri, F.; Gharbi, N.

    2012-11-15

    Highlights: ► Flake-like nanocrystalline V{sub 4}O{sub 9} was synthesized by a solvothermal route. ► Photocatalytic activity has been evaluated by the degradation of methylene blue under visible light irradiation. ► V{sub 4}O{sub 9} nanoflakes exhibited much higher photocatalytic activity two times higher than the bulk V{sub 2}O{sub 5}. -- Abstract: Flake-like nanocrystalline V{sub 4}O{sub 9} has been successfully synthesized by solvothermal process using V{sub 2}O{sub 5} as vanadium source and phenolphthalein as a reducing agent and a structure-directing template. Techniques X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and ultraviolet–visible (UV–vis) spectroscopy have been used to characterize the structure, the morphology and the composition of the material. The photocatalytic activity of the material has been evaluated by the degradation of methylene blue under visible light irradiation. As a result, after the lapse of 150 min, around 93.54% bleaching was observed, with V{sub 4}O{sub 9} nanoflakes yielding more photodegradation compared to that of bulk V{sub 2}O{sub 5}. This presents a degradation percentage of about 44.67%.

  7. Monitoring accelerated carbonation on standard Portland cement mortar by nonlinear resonance acoustic test

    NASA Astrophysics Data System (ADS)

    Eiras, J. N.; Kundu, T.; Popovics, J. S.; Monzó, J.; Borrachero, M. V.; Payá, J.

    2015-03-01

    Carbonation is an important deleterious process for concrete structures. Carbonation begins when carbon dioxide (CO2) present in the atmosphere reacts with portlandite producing calcium carbonate (CaCO3). In severe carbonation conditions, C-S-H gel is decomposed into silica gel (SiO2.nH2O) and CaCO3. As a result, concrete pore water pH decreases (usually below 10) and eventually steel reinforcing bars become unprotected from corrosion agents. Usually, the carbonation of the cementing matrix reduces the porosity, because CaCO3 crystals (calcite and vaterite) occupy more volume than portlandite. In this study, an accelerated carbonation-ageing process is conducted on Portland cement mortar samples with water to cement ratio of 0.5. The evolution of the carbonation process on mortar is monitored at different levels of ageing until the mortar is almost fully carbonated. A nondestructive technique based on nonlinear acoustic resonance is used to monitor the variation of the constitutive properties upon carbonation. At selected levels of ageing, the compressive strength is obtained. From fractured surfaces the depth of carbonation is determined with phenolphthalein solution. An image analysis of the fractured surfaces is used to quantify the depth of carbonation. The results from resonant acoustic tests revealed a progressive increase of stiffness and a decrease of material nonlinearity.

  8. Production of cyclodextrin glycosyltransferase by immobilized Bacillus sp. on chitosan matrix.

    PubMed

    Eş, Ismail; Ribeiro, Maycon Carvalho; Dos Santos Júnior, Samuel Rodrigues; Khaneghah, Amin Mousavi; Rodriguez, Armando Garcia; Amaral, André Corrêa

    2016-10-01

    The whole-cell immobilization on chitosan matrix was evaluated. Bacillus sp., as producer of CGTase, was grown in solid-state and batch cultivation using three types of starches (cassava, potato and cornstarch). Biomass growth and substrate consumption were assessed by flow cytometry and modified phenol-sulfuric acid assays, respectively. Qualitative analysis of CGTase production was determined by colorless area formation on solid culture containing phenolphthalein. Scanning electron microscopy (SEM) analysis demonstrated that bacterial cells were immobilized on chitosan matrix efficiently. Free cells reached very high numbers during batch culture while immobilized cells maintained initial inoculum concentration. The maximum enzyme activity achieved by free cells was 58.15 U ml(-1) (36 h), 47.50 U ml(-1) (36 h) and 68.36 U ml(-1) (36 h) on cassava, potato and cornstarch, respectively. CGTase activities for immobilized cells were 82.15 U ml(-1) (18 h) on cassava, 79.17 U ml(-1) (12 h) on potato and 55.37 U ml(-1) (in 6 h and max 77.75 U ml(-1) in 36 h) on cornstarch. Application of immobilization technique increased CGTase activity significantly. The immobilized cells produced CGTase with higher activity in a shorter fermentation time comparing to free cells. PMID:27194141

  9. Carbon analysis for inspecting carbonation of concrete using a TEA CO2 laser-induced plasma.

    PubMed

    Kagawa, Kiichiro; Idris, Nasrullah; Wada, Munehide; Kurniawan, Hendrik; Tsuyuki, Kenichiro; Miura, Satoru

    2004-08-01

    It has been demonstrated that a spectrochemical analysis of carbon using the laser plasma method can be successfully applied to inspect the carbonation of concrete by detecting carbon produced in aged concrete by a chemical reaction of Ca(OH)2 with CO2 gas in environmental air, turning into CaCO3, which induces degradation of the quality of building concrete. A comparative study has been made using a TEA CO2 laser (500-1000 mJ) and a Q-switched Nd-YAG laser (50-200 mJ) to search for the optimum conditions for carbon analysis, proving the advantage of the TEA CO2 laser for this purpose. Also, it was clarified that laser irradiation with suitable defocusing conditions is a crucial point for obtaining high sensitivity in the detection of carbon. Practical experiments on the inspection of carbonation were carried out using both a concrete sample that had been intentionally carbonated by exposure to high concentrations of CO2 gas and a naturally carbonated concrete sample. As a result, good coincidence was observed between the laser method and the ordinary method, which uses the chemical indicator phenolphthalein, implying that this laser technique is applicable as an in situ quantitative method of inspection for carbonation of concrete. PMID:18070383

  10. Mixing in colliding, ultrasonically levitated drops.

    PubMed

    Chainani, Edward T; Choi, Woo-Hyuck; Ngo, Khanh T; Scheeline, Alexander

    2014-02-18

    Lab-in-a-drop, using ultrasonic levitation, has been actively investigated for the last two decades. Benefits include lack of contact between solutions and an apparatus and a lack of sample cross-contamination. Understanding and controlling mixing in the levitated drop is necessary for using an acoustically levitated drop as a microreactor, particularly for studying kinetics. A pulsed electrostatic delivery system enables addition and mixing of a desired-volume droplet with the levitated drop. Measurement of mixing kinetics is obtained by high-speed video monitoring of a titration reaction. Drop heterogeneity is visualized as 370 nl of 0.25 M KOH (pH: 13.4) was added to 3.7 μL of 0.058 M HCl (pH: 1.24). Spontaneous mixing time is about 2 s. Following droplet impact, the mixed drop orbits the levitator axis at about 5 Hz during homogenization. The video's green channel (maximum response near 540 nm) shows the color change due to phenolphthalein absorption. While mixing is at least an order of magnitude faster in the levitated drop compared with three-dimensional diffusion, modulation of the acoustic waveform near the surface acoustic wave resonance frequency of the levitated drop does not substantially reduce mixing time. PMID:24460103

  11. Number of bacteria decomposing organic phosphorus compounds and phosphatase activity in the sand of two marine beaches differing in the level of anthropopressure.

    PubMed

    Mudryk, Z J; Perliński, P; Antonowicz, J; Robak, D

    2015-12-30

    Number of heterotrophic bacteria ability to decompose organic phosphorus compounds and the level of phosphatase activity in the sand of two marine beaches (southern coast of the Baltic Sea) differing in the level of anthropopressure were studied. The study showed that the number of bacteria and level phosphatase activity were higher in the sand of the beach subjected to stronger anthropopressure. In both studied beaches bacteria hydrolysing DNA were the most numerous (92.7-302.8 CFU·g(-1) d.w.). The least numerous were phytin (26.0·10(3) CFU·g(-1) d.w.) and phenolphthalein diphosphate (11.1·10(3) CFU·g(-1) d.w.) decomposing bacteria. Number of bacteria able to attack tested organic phosphorus compounds were the most numerous in dry zones (10.77-739.92 CFU·g(-1) d.w.) then wet zones (3.34-218.15 CFU·g(-1) d.w.). In both studied beaches bacteria hydrolysing organic phosphorus compounds and phosphatase activity generally were more numerous in surface sand layer. Seasonal variation in the occurrence of bacteria in both studied beaches was observed.

  12. Optimization of nanolime solvent for the consolidation of coarse porous limestone

    NASA Astrophysics Data System (ADS)

    Borsoi, Giovanni; Lubelli, Barbara; van Hees, Rob; Veiga, Rosário; Silva, António Santos

    2016-09-01

    The potentialities of nanomaterials for application in the field of conservation have been widely investigated in the last two decades. Among nanomaterials, nanolimes, i.e., dispersions of lime nanoparticles in alcohols are promising consolidating products for calcareous materials. Nanolimes are effective in recovering the very superficial loss of cohesion of decayed materials, but they do not always provide sufficient mass consolidation. This limitation is mainly related to the deposition of the nanoparticles nearby the surface of the material. Experimental research has been set up with the aim of improving the in-depth deposition of lime nanoparticles. Previous research by the authors has shown that nanolime deposition within a substrate can be controlled by adapting the nanolimes properties (kinetic stability and evaporation rate) to the moisture transport behavior of the substrate. Nanolime properties can be modified by the use of different solvents. In this research, nanolime dispersions have been further optimized for application on Maastricht limestone, a coarse porous limestone. Firstly, nanolimes were synthesized and dispersed in ethanol and/or water, both pure and mixed in different percentages. Subsequently, based on the kinetic stability of the nanolime dispersions, the most promising solvent mixtures were selected and applied on the limestone. The deposition of lime nanoparticles within the limestone was studied by phenolphthalein test, optical microscopy and scanning electron microscopy. The results confirm that nanolime dispersed in a mixture of ethanol (95 %) and water (5 %) can guarantee a better nanoparticles in-depth deposition within coarse porous substrates, when compared to dispersions in pure ethanol.

  13. Quantitative estimation of carbonation and chloride penetration in reinforced concrete by laser-induced breakdown spectroscopy

    NASA Astrophysics Data System (ADS)

    Eto, Shuzo; Matsuo, Toyofumi; Matsumura, Takuro; Fujii, Takashi; Tanaka, Masayoshi Y.

    2014-11-01

    The penetration profile of chlorine in a reinforced concrete (RC) specimen was determined by laser-induced breakdown spectroscopy (LIBS). The concrete core was prepared from RC beams with cracking damage induced by bending load and salt water spraying. LIBS was performed using a specimen that was obtained by splitting the concrete core, and the line scan of laser pulses gave the two-dimensional emission intensity profiles of 100 × 80 mm2 within one hour. The two-dimensional profile of the emission intensity suggests that the presence of the crack had less effect on the emission intensity when the measurement interval was larger than the crack width. The chlorine emission spectrum was measured without using the buffer gas, which is usually used for chlorine measurement, by collinear double-pulse LIBS. The apparent diffusion coefficient, which is one of the most important parameters for chloride penetration in concrete, was estimated using the depth profile of chlorine emission intensity and Fick's law. The carbonation depth was estimated on the basis of the relationship between carbon and calcium emission intensities. When the carbon emission intensity was statistically higher than the calcium emission intensity at the measurement point, we determined that the point was carbonated. The estimation results were consistent with the spraying test results using phenolphthalein solution. These results suggest that the quantitative estimation by LIBS of carbonation depth and chloride penetration can be performed simultaneously.

  14. A full automatic device for sampling small solution volumes in photometric titration procedure based on multicommuted flow system.

    PubMed

    Borges, Sivanildo S; Vieira, Gláucia P; Reis, Boaventura F

    2007-01-01

    In this work, an automatic device to deliver titrant solution into a titration chamber with the ability to determine the dispensed volume of solution, with good precision independent of both elapsed time and flow rate, is proposed. A glass tube maintained at the vertical position was employed as a container for the titrant solution. Electronic devices were coupled to the glass tube in order to control its filling with titrant solution, as well as the stepwise solution delivering into the titration chamber. The detection of the titration end point was performed employing a photometer designed using a green LED (lambda=545 nm) and a phototransistor. The titration flow system comprised three-way solenoid valves, which were assembled to allow that the steps comprising the solution container loading and the titration run were carried out automatically. The device for the solution volume determination was designed employing an infrared LED (lambda=930 nm) and a photodiode. When solution volume delivered from proposed device was within the range of 5 to 105 mul, a linear relationship (R = 0.999) between the delivered volumes and the generated potential difference was achieved. The usefulness of the proposed device was proved performing photometric titration of hydrochloric acid solution with a standardized sodium hydroxide solution and using phenolphthalein as an external indicator. The achieved results presented relative standard deviation of 1.5%. PMID:18317510

  15. Effect of mineral additives (natural pozzolana and sand of dunes) by substitution of cement on the performance and durability of mortars

    NASA Astrophysics Data System (ADS)

    Saidi, M.; Safi, B.

    2016-04-01

    The objective of our work consists of the study of the substitution effects of clinker by mineral additions such as: natural pozzolana (PZ) and the sand of dunes (SD) finely crushed on the mechanical properties and the durability of the mortars worked out according to various combinations containing these additions. The results from this research confirm that the substitution of 20% to 30% of cement APC (Artificial Portland Cement) by additions in binary cement (APC + PZ) or ternary (APC + PZ + SD) contributes positively to the mechanical strength of mortars and resistance to the chemical attacks in various corrosive conditions such as: hydrochloric acid, sulfuric acid and nitric acid. The mechanical strength of the different variants is comparable to those of the APC. The test results of the weight loss and phenolphthalein shows that the chemical resistance of variants (PZ20) and (PZ20 with SD5) are larger compared to the reference mortar APC and other variants. This study shows that adding value by substituting a part of clinker. This substitution can save 20% to 30% of clinker used for the manufacture of cement; this will have a beneficial effect for cement and economically (less energy spent for the clinker burning). This study contributes to the protection of the environment as to produce one ton of clinker generates about one ton of CO2 is harmful to the atmosphere. Based on our results we will reduce from 20% to 30% CO2 gas responsible for the greenhouse effect.

  16. Number of bacteria decomposing organic phosphorus compounds and phosphatase activity in the sand of two marine beaches differing in the level of anthropopressure.

    PubMed

    Mudryk, Z J; Perliński, P; Antonowicz, J; Robak, D

    2015-12-30

    Number of heterotrophic bacteria ability to decompose organic phosphorus compounds and the level of phosphatase activity in the sand of two marine beaches (southern coast of the Baltic Sea) differing in the level of anthropopressure were studied. The study showed that the number of bacteria and level phosphatase activity were higher in the sand of the beach subjected to stronger anthropopressure. In both studied beaches bacteria hydrolysing DNA were the most numerous (92.7-302.8 CFU·g(-1) d.w.). The least numerous were phytin (26.0·10(3) CFU·g(-1) d.w.) and phenolphthalein diphosphate (11.1·10(3) CFU·g(-1) d.w.) decomposing bacteria. Number of bacteria able to attack tested organic phosphorus compounds were the most numerous in dry zones (10.77-739.92 CFU·g(-1) d.w.) then wet zones (3.34-218.15 CFU·g(-1) d.w.). In both studied beaches bacteria hydrolysing organic phosphorus compounds and phosphatase activity generally were more numerous in surface sand layer. Seasonal variation in the occurrence of bacteria in both studied beaches was observed. PMID:26522162

  17. Structure and properties of PVDF membrane with PES-C addition via thermally induced phase separation process

    NASA Astrophysics Data System (ADS)

    Wu, Lishun; Sun, Junfen

    2014-12-01

    Polyvinylidene fluoride (PVDF) membrane and PVDF membrane with phenolphthalein polyethersulfone (PES-C) addition were prepared via thermally induced phase separation (TIPS) method by using diphenyl carbonate (DPC) and dimethyl acetamide (DMAc) as mixed diluents. The effects of coagulation temperature and pre-evaporation time on structure and properties of membranes were studied. The changes of sewage flux in MBR and the attenuation coefficient of sewage flux were investigated. The resistance distributions of PVDF and PVDF/PES-C membranes were compared by resistance analysis. Membrane composition and structure were characterized by ATR-FTIR, TGA, SEM and AFM. The foulant on membranes was analyzed by FTIR. The contact angle of PVDF/PES-C membrane was lower than that of PVDF membrane. A thinner skin layer and a porous cellular support layer formed in PVDF/PES-C membrane and resulted in a higher porosity and pure water flux. The pure water flux and porosity of PVDF/PES-C membrane increased with rising coagulation temperature and decreased with extending pre-evaporation time. The flux attenuation coefficient, the cake layer resistance and internal fouling resistance of PVDF/PES-C membrane in MBR were smaller than those of PVDF membrane in MBR. The FTIR spectrum of foulant on membrane indicated that the foulant on PVDF/PES-C membrane was mostly composed of protein and polysaccharide, while the foulant on pure PVDF membrane included biopolymer clusters besides protein and polysaccharide.

  18. Sequential injection redox or acid-base titration for determination of ascorbic acid or acetic acid.

    PubMed

    Lenghor, Narong; Jakmunee, Jaroon; Vilen, Michael; Sara, Rolf; Christian, Gary D; Grudpan, Kate

    2002-12-01

    Two sequential injection titration systems with spectrophotometric detection have been developed. The first system for determination of ascorbic acid was based on redox reaction between ascorbic acid and permanganate in an acidic medium and lead to a decrease in color intensity of permanganate, monitored at 525 nm. A linear dependence of peak area obtained with ascorbic acid concentration up to 1200 mg l(-1) was achieved. The relative standard deviation for 11 replicate determinations of 400 mg l(-1) ascorbic acid was 2.9%. The second system, for acetic acid determination, was based on acid-base titration of acetic acid with sodium hydroxide using phenolphthalein as an indicator. The decrease in color intensity of the indicator was proportional to the acid content. A linear calibration graph in the range of 2-8% w v(-1) of acetic acid with a relative standard deviation of 4.8% (5.0% w v(-1) acetic acid, n=11) was obtained. Sample throughputs of 60 h(-1) were achieved for both systems. The systems were successfully applied for the assays of ascorbic acid in vitamin C tablets and acetic acid content in vinegars, respectively.

  19. A Low-Cost Device for Automatic Photometric Titrations

    NASA Astrophysics Data System (ADS)

    Rocha, Fábio R. P.; Reis, Boaventura F.

    2000-02-01

    Electronics is an important topic in chemistry courses. However, the introduction of basic concepts is often difficult and the lab instruments are frequently seen as "black boxes". To address this problem, we propose the construction of a simple, low-cost (about $150 U.S.) automatic photometric titrator employing a light-emitting diode (LED) and a phototransistor. The electronic circuit can be assembled by the students themselves. The device was employed to implement a common procedure in chemical labs, making feasible the introduction of concepts related to electronics in undergraduate chemistry courses. The titrator is able to work automatically, since a feedback system permits stopping the addition of titrant solution when the end-point is achieved. With this demonstration, it can be stressed that automatic procedures can be implemented without expensive instruments. Additionally, a classical procedure becomes more attractive to the students and its importance to chemical analysis can be emphasized. The feasibility of the titrator was demonstrated by acid-base titrations of HCl solutions with NaOH in the presence of phenolphthalein and by iodimetric determination of ascorbic acid in vitamin C tablets and lemon juice. Precise results (0.7% relative standard deviation, n = 10) in agreement at the 95% confidence level with those attained by a conventional procedure were obtained.

  20. Qualitative Analysis of Fourteen White Solids and Two Mixtures Using Household Chemicals

    NASA Astrophysics Data System (ADS)

    Oliver-Hoyo, Maria; Allen, Deedee; Solomon, Sally; Brook, Bryan; Ciraolo, Justine; Daly, Shawn; Jackson, Leia

    2001-11-01

    This is a revised and expanded version of a previously published qualitative analysis scheme for the identification of 11 white solids using materials readily available in drugstores, supermarkets, or variety stores. Phenolphthalein has been eliminated because the FDA banned its use in over-the-counter laxatives; instead, tests for pH are conducted using red cabbage indicator. Once commonly used by diabetics to test urine, copper reduction tablets are no longer widely available and are replaced by a mixture of ingredients. Three white solids and two types of mixtures, commercial antacid tablets and baking powder, have been added to the scheme. All procedures can be done with the simplest of equipment. Amounts of solids are measured volumetrically and heat is supplied by contact with hot tap water. The use of household chemicals reduces waste disposal problems while making the experiment suitable for a laboratory exercise in a distance-learning course. This experiment can be adapted for many levels of instruction. In middle school only the safer tests should be included; honors general chemistry students can be asked to design an analysis scheme for the 14 household chemicals.

  1. Tracer-monitored flow titrations.

    PubMed

    Sasaki, Milton K; Rocha, Diogo L; Rocha, Fábio R P; Zagatto, Elias A G

    2016-01-01

    The feasibility of implementing tracer-monitored titrations in a flow system is demonstrated. A dye tracer is used to estimate the instant sample and titrant volumetric fractions without the need for volume, mass or peak width measurements. The approach was applied to spectrophotometric flow titrations involving variations of sample and titrant flow-rates (i.e. triangle programmed technique) or concentration gradients established along the sample zone (i.e. flow injection system). Both strategies required simultaneous monitoring of two absorbing species, namely the titration indicator and the dye tracer. Mixing conditions were improved by placing a chamber with mechanical stirring in the analytical path aiming at to minimize diffusional effects. Unlike most of flow-based titrations, the innovation is considered as a true titration, as it does not require a calibration curve thus complying with IUPAC definition. As an application, acidity evaluation in vinegars involving titration with sodium hydroxide was selected. Phenolphthalein and brilliant blue FCF were used as indicator and dye tracer, respectively. Effects of sample volume, titrand/titrant concentrations and flow rates were investigated aiming at improved accuracy and precision. Results were reliable and in agreement with those obtained by a reference titration procedure. PMID:26703261

  2. Evaluating the seasonal changes of water quality of the Değirmendere and Galyan Rivers (Trabzon, Turkey).

    PubMed

    Altun, Lokman; Yilmaz, Murat; Acar, Cengiz; Turna, Ibrahim; Başkent, E Zeki; Bilgili, Ertuğrul

    2003-10-01

    The Değirmendere and Galyan (Değirmendere tributary) Rivers that discharge their water into the Black Sea are important watersheds in the northeastern part of Turkey. Water quality parameters were sampled from 1997 through 2001 for each year at five sites (three for Galyan, two for Degirmendere) along 29 and 42 km gradients, respectively covering all seasons. Surface water was collected from the sites and analyzed for temperature, total alkaline (MAAL), total dissolved solids (TDS), dissolved oxygen (DO), pH, conductivity (EC), nitrate (NO3), nitrite (NO2), total hardness (TH), phenolphthalein alkalinities (PAL) and organic matter (PV). Seasonal changes of water quality were analyzed statistically for both Rivers and evaluated according to the TS 266, EU and WHO standards. The analysis of variance results showed that Ca, Mg, MAL, NO3, pH, TDS and TH parameters of the Değirmendere River and Ca, DO, EC, MAL, NO3, pH and TH parameters of the Galyan River showed seasonal differences (p<0.05). The maximum values of the water pollution parameters for the two Rivers were below the threshold values throughout the study period. When both Rivers were compared, the mean values of the pollution parameters of the Degirmendere River were higher than those of the Galyan River and very close the limits. The results indicate that both Rivers can be used for the production of potable water during all seasons but only with an advanced treatment in the Değirmendere and a moderate treatment in the Galyan River, and for indirect and non-contact recreational activities. PMID:15248656

  3. Effect of galactosamine-induced hepatic UDP-glucuronic acid depletion on acetaminophen elimination in rats. Dispositional differences between hepatically and extrahepatically formed glucuronides of acetaminophen and other chemicals.

    PubMed

    Gregus, Z; Madhu, C; Goon, D; Klaassen, C D

    1988-01-01

    Galactosamine (GAL) markedly depletes hepatic UDP-glucuronic acid (UDP-GA) whereas extrahepatic UDP-GA is minimally affected. This suggests that GAL predominantly inhibits hepatic glucuronidation. Therefore, the effect of GAL-induced hepatic UDP-GA depletion was examined in bile duct-cannulated rats to determine the role of hepatic glucuronidation in the disposition of acetaminophen (AA). GAL markedly altered the fate of AA-glucuronide but had little or no effect upon other AA metabolites. GAL decreased the biliary excretion of AA-glucuronide up to 92%, whereas reductions in blood levels and urinary excretion of AA-glucuronide did not exceed 50%. This suggests that AA-glucuronide excreted in bile is predominantly of hepatic origin whereas AA-glucuronide found in blood and urine is derived from both hepatic and extrahepatic tissues. Data in the present and previous studies [Gregus, Watkins, Thompson, Klaassen: J. Pharmacol. Exp. Ther. 225, 256, (1983)] indicate that GAL greatly reduced the biliary excretion of AA- and valproic acid-glucuronide whereas the biliary excretion of the glucuronides of phenolphthalein, iopanoic acid, bilirubin, and diethylstilbestrol was only partially decreased. This difference appears to be largely due to differential contributions by the liver and extrahepatic tissues in the glucuronidation of various compounds as well as the availability of glucuronides formed in extrahepatic tissues for biliary excretion. Specifically, the extrahepatically formed glucuronide conjugates of AA and valproic acid are not readily available for biliary excretion whereas the glucuronides of the other compounds are readily excreted into bile.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Development of UDP-glucuronosyltransferase activity toward digitoxigenin-monodigitoxoside in neonatal rats.

    PubMed

    Watkins, J B; Klaassen, C D

    1985-01-01

    Glucuronidation is low or undetectable in embryonic and early fetal tissues and changes to adult levels at rates depending on the acceptor, tissue, and species. Because other data indicate there may be a specific UDP-glucuronosyltransferase (GT) in the liver of adult rats that glucuronidates digitoxigenin-monodigitoxoside (DIG), the development of GT activity in neonatal rats toward DIG was compared with that of other acceptors. Conjugation of p-nitrophenol and 1-naphthol was higher at birth and decreased to adult levels by 20 days of age. Glucuronidation of chloramphenicol, morphine, valproic acid, and bilirubin increased from birth to adult activity by 20 days of age. Conjugation of phenolphthalein, estrone, and diethylstilbestrol was low in 1-day-old rats and higher than adult in 20-day-old animals. In contrast, glucuronidation of DIG was barely detectable (9% of adult) in 20-day-old rats. The concentration of UDP-glucuronic acid was 50% of adult levels at birth and increased to adult values by 10 days of age. Administration of 3-methylcholanthrene on days 6 to 9 after birth significantly stimulated GT activity toward 1-naphthol, p-nitrophenol, and morphine, whereas phenobarbital precociously increased conjugation of chloramphenicol, valproic acid, morphine, and diethylstilbestrol. Pregnenolone-16 alpha-carbonitrile enhanced the development of GT activity toward morphine, chloramphenicol, valproic acid, bilirubin, diethylstilbestrol, and estrone. Glucuronidation of DIG was not increased after 3-methylcholanthrene or phenobarbital, but could be induced after pregnenolone-16 alpha-carbonitrile to 7% of adult values in 10-day-old rats.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. [Preparation of molecularly imprinted polymers using dummy template and the applications in selective solid-phase extraction of seven bisphenols from human urine, bovine serum and beer samples].

    PubMed

    Yang, Jiajia; Li, Yun; Wang Jinchengt; Sun, Xiaoli; Chen, Jiping

    2015-05-01

    A molecularly imprinted polymer (MIP) for selective recognition of seven bisphenols (BPs) was prepared using dummy template phenolphthalein (PP) by bulk polymerization. The characterization results of scanning electron microscopy and nitrogen adsorption-desorption measurements showed that the prepared PP-MIP possessed narrow particle diameter distribution (40-60 µm), a specific surface area (S(BET)) of 359.77 m2/g and a total pore volume (Vt) of 0.730 cm3/g. The adsorption capacity for bisphenol A (BPA) of PP-MIP was evaluated by static adsorption experiment. And the Scatchard analysis revealed that the maximum specific adsorption capacity of PP-MIP was 4.661 µmol/g. Good class selectivity for BPA and its six structural analogues of bisphenol B (BPB) , bisphenol E (BPE), bisphenol AF (BPAF), bisphenol S (BPS), bisphenol AP (BPAP) and bisphenol Z (BPZ) was demonstrated by the chromatographic evaluation experiment. The prepared PP-MIP was successfully used as solid-phase extraction (SPE) sorbent for the separation and purification of the seven BPs in human urine, bovine serum and beer samples. Meanwhile, an accurate and sensitive MIP-SPE-HPLC method was established for the determination of the seven BPs in human urine, bovine serum and beer samples. The limits of detection (LODs) for the three samples were in the range of 1.2-2.0 µg/L. The results showed that good linearities were obtained in the range of 0.02-2 mg/L for the seven BPs and the correlation coefficients (r) were higher than 0.999 8. The recoveries of the BPs spiked in blank samples at two spiked levels (100 and 500 µg/L for each BP) were in the range of 90.1%-107.1% with the RSDs ≤ 8.1%. The proposed method is simple and reliable for the rapid detection of the seven BPs in human urine, bovine serum and beer samples. PMID:26387203

  6. Inhibitory effect of ciprofloxacin on β-glucuronidase-mediated deconjugation of mycophenolic acid glucuronide.

    PubMed

    Kodawara, Takaaki; Masuda, Satohiro; Yano, Yoshitaka; Matsubara, Kazuo; Nakamura, Toshiaki; Masada, Mikio

    2014-07-01

    The interaction between mycophenolate (MPA) and quinolone antibiotics such as ciprofloxacin is considered to reduce the enterohepatic recycling of MPA, which is biotransformed in the intestine from MPA glucuronide (MPAG) conjugate excreted via the biliary system; however, the molecular mechanism underlying this biotransformation of MPA is still unclear. In this study, an in vitro system was established to evaluate β-glucuronidase-mediated deconjugation and to examine the influence of ciprofloxacin on the enzymatic deconjugation of MPAG and MPA resynthesis. Resynthesis of MPA via deconjugation of MPAG increased in a time-dependent manner from 5 to 60 min in the presence of β-glucuronidase. Ciprofloxacin and phenolphthalein-β-d-glucuronide (PhePG), a typical β-glucuronidase substrate, significantly decreased the production of MPA from MPAG in the β-glucuronidase-mediated deconjugation system. In addition, enoxacin significantly inhibited the production of MPA from MPAG, while levofloxacin and ofloxacin had no inhibitory effect on MPA synthesis. Pharmacokinetic analysis revealed that ciprofloxacin showed a dose-dependent inhibitory effect on MPA production from MPAG via β-glucuronidase with a half-maximal inhibitory concentration (IC50 ) value of 30.4 µm. While PhePG inhibited the β-glucuronidase-mediated production of MPA from MPAG in a competitive manner, ciprofloxacin inhibited MPA synthesis via noncompetitive inhibition. These findings suggest that the reduction in the serum MPA concentration during the co-administration of ciprofloxacin is at least in part due to the decreased enterohepatic circulation of MPA because of noncompetitive inhibition of deconjugation of MPAG by intestinal β-glucuronidase.

  7. Comparative Evaluation of Four Presumptive Tests for Blood to Detect Epithelial Injury on Fish

    SciTech Connect

    Colotelo, Alison HA; Smokorowski, Karen; Haxton, Tim; Cooke, Steven J.

    2014-06-01

    Current methods of fish epithelial injury detection are limited to gross macroscopic examination that has a subjective bias as well as an inability to reliably quantify the degree of injury. Fluorescein, a presumptive test for blood, has been shown to have the capability to detect and quantify fish epithelial injury. However, there are several other presumptive tests for blood (Bluestar*, phenolphthalein, and HemastixH) that may have benefits over the use of fluorescein, particularly for field research on wild fish. This study investigated the capabilities of these four tests to detect and quantify a variety of injuries commonly encountered by fish (abrasion, cuts, fin frays, and punctures) using the freshwater bluegill Lepomis macrochirus as a model. Fluorescein was consistently found to be the most reliable (i.e., detected the highest proportion of true positive results and rarely detected false positive reactions) of the four presumptive tests for blood compared. Further testing was conducted to examine the reliability of fluorescein. By 24 h after an injury was inflicted, the injury was no longer detectable by fluorescein, and when fluorescein was applied to an injured fish, the fluorescein was no longer detectable 3 h after application. In a comparison of two common anaesthetics used in fisheries research, there was no significant difference in the proportion of injury detected when 3- aminobenzoic acid ethyl ester methanesulfate (tricaine) was used compared with a clove oil and ethanol (1:9) solution. In summary, fluorescein was the most reliable presumptive test for blood examined in this study for the detection and quantification of recent (hours) fish epithelial injury.

  8. Physical Selectivity of Molecularly Imprinted polymers evaluated through free volume size distributions derived from Positron Lifetime Spectroscopy

    NASA Astrophysics Data System (ADS)

    Pasang, T.; Ranganathaiah, C.

    2015-06-01

    The technique of imprinting molecules of various sizes in a stable structure of polymer matrix has derived multitudes of applications. Once the template molecule is extracted from the polymer matrix, it leaves behind a cavity which is physically (size and shape) and chemically (functional binding site) compatible to the particular template molecule. Positron Annihilation Lifetime Spectroscopy (PALS) is a well known technique to measure cavity sizes precisely in the nanoscale and is not being used in the field of MIPs effectively. This method is capable of measuring nanopores and hence suitable to understand the physical selectivity of the MIPs better. With this idea in mind, we have prepared molecular imprinted polymers (MIPs) with methacrylicacid (MAA) as monomer and EGDMA as cross linker in different molar ratio for three different size template molecules, viz. 4-Chlorophenol (4CP)(2.29 Å), 2-Nephthol (2NP) (3.36 Å) and Phenolphthalein (PP) (4.47Å). FTIR and the dye chemical reactions are used to confirm the complete extraction of the template molecules from the polymer matrix. The free volume size and its distribution have been derived from the measured o-Ps lifetime spectra. Based on the free volume distribution analysis, the percentage of functional cavities for the three template molecules are determined. Percentage of functional binding cavities for 4-CP molecules has been found out to be 70.2% and the rest are native cavities. Similarly for 2NP it is 81.5% and nearly 100% for PP. Therefore, PALS method proves to be very precise and accurate for determining the physical selectivity of MIPs.

  9. Study of dynamics and crystallization kinetics of 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile at ambient and elevated pressure

    NASA Astrophysics Data System (ADS)

    Adrjanowicz, K.; Kaminski, K.; Paluch, M.; Ngai, K. L.; Yu, Lian

    2012-06-01

    The organic liquid ROY, i.e., 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile, has been a subject of detailed study in the last few years. One interest in ROY lies in its polymorph-dependent fast crystal growth mode below and above the glass transition temperature. This growth mode is not diffusion controlled, and the possibility that it is enabled by secondary relaxation had been suggested. However, a previous study by dielectric relaxation spectroscopy had not been able to find any resolved secondary relaxation. The present paper reports new dielectric measurements of ROY in the liquid and glassy states at ambient pressure and elevated pressure, which were performed to provide more insight into the molecular dynamics as well as the crystallization tendency of ROY. In the search of secondary relaxation, a special glassy state of ROY was prepared by applying high pressure to the liquid state, from which secondary relaxation was possibly resolved. Thus, the role of secondary relaxation in crystallization of ROY remains to be clarified. Notwithstanding, the secondary relaxation present is not necessarily the sole enabler of crystallization. In an effort to search for possible cause of crystallization other than secondary relaxation, we also performed crystallization kinetics studies of ROY at different T and P combinations while keeping the structural relaxation time constant. The results show that crystallization of ROY speeds up with pressure, opposite to the trend found in the crystallization of ibuprofen studied up to 1 GPa. The dielectric relaxation and thermodynamic properties of ROY with phenolphthalein dimethylether (PDE) are similar in many respects, but PDE does not crystallize. Taking all the above into account, besides the secondary relaxation, the specific chemical structure, molecular interactions and packing of the molecules are additional factors that could affect the kinetics of crystallization found in ROY.

  10. Novel approaches to analysis by flow injection gradient titration.

    PubMed

    Wójtowicz, Marzena; Kozak, Joanna; Kościelniak, Paweł

    2007-09-26

    Two novel procedures for flow injection gradient titration with the use of a single stock standard solution are proposed. In the multi-point single-line (MP-SL) method the calibration graph is constructed on the basis of a set of standard solutions, which are generated in a standard reservoir and subsequently injected into the titrant. According to the single-point multi-line (SP-ML) procedure the standard solution and a sample are injected into the titrant stream from four loops of different capacities, hence four calibration graphs are able to be constructed and the analytical result is calculated on the basis of a generalized slope of these graphs. Both approaches have been tested on the example of spectrophotometric acid-base titration of hydrochloric and acetic acids with using bromothymol blue and phenolphthalein as indicators, respectively, and sodium hydroxide as a titrant. Under optimized experimental conditions the analytical results of precision less than 1.8 and 2.5% (RSD) and of accuracy less than 3.0 and 5.4% (relative error (RE)) were obtained for MP-SL and SP-ML procedures, respectively, in ranges of 0.0031-0.0631 mol L(-1) for samples of hydrochloric acid and of 0.1680-1.7600 mol L(-1) for samples of acetic acid. The feasibility of both methods was illustrated by applying them to the total acidity determination in vinegar samples with precision lower than 0.5 and 2.9% (RSD) for MP-SL and SP-ML procedures, respectively.

  11. [Preparation of molecularly imprinted polymers using dummy template and the applications in selective solid-phase extraction of seven bisphenols from human urine, bovine serum and beer samples].

    PubMed

    Yang, Jiajia; Li, Yun; Wang Jinchengt; Sun, Xiaoli; Chen, Jiping

    2015-05-01

    A molecularly imprinted polymer (MIP) for selective recognition of seven bisphenols (BPs) was prepared using dummy template phenolphthalein (PP) by bulk polymerization. The characterization results of scanning electron microscopy and nitrogen adsorption-desorption measurements showed that the prepared PP-MIP possessed narrow particle diameter distribution (40-60 µm), a specific surface area (S(BET)) of 359.77 m2/g and a total pore volume (Vt) of 0.730 cm3/g. The adsorption capacity for bisphenol A (BPA) of PP-MIP was evaluated by static adsorption experiment. And the Scatchard analysis revealed that the maximum specific adsorption capacity of PP-MIP was 4.661 µmol/g. Good class selectivity for BPA and its six structural analogues of bisphenol B (BPB) , bisphenol E (BPE), bisphenol AF (BPAF), bisphenol S (BPS), bisphenol AP (BPAP) and bisphenol Z (BPZ) was demonstrated by the chromatographic evaluation experiment. The prepared PP-MIP was successfully used as solid-phase extraction (SPE) sorbent for the separation and purification of the seven BPs in human urine, bovine serum and beer samples. Meanwhile, an accurate and sensitive MIP-SPE-HPLC method was established for the determination of the seven BPs in human urine, bovine serum and beer samples. The limits of detection (LODs) for the three samples were in the range of 1.2-2.0 µg/L. The results showed that good linearities were obtained in the range of 0.02-2 mg/L for the seven BPs and the correlation coefficients (r) were higher than 0.999 8. The recoveries of the BPs spiked in blank samples at two spiked levels (100 and 500 µg/L for each BP) were in the range of 90.1%-107.1% with the RSDs ≤ 8.1%. The proposed method is simple and reliable for the rapid detection of the seven BPs in human urine, bovine serum and beer samples.

  12. Measurements of Molecular Mixing in a High Schmidt Number Rayleigh-Taylor Mixing Layer

    SciTech Connect

    Mueschke, N J; Schilling, O; Youngs, D L; Andrews, M

    2007-12-03

    Molecular mixing measurements are performed for a high Schmidt number (Sc {approx} 10{sup 3}), small Atwood number (A {approx} 7.5 x 10{sup -4}) buoyancy-driven turbulent Rayleigh-Taylor mixing layer in a water channel facility. Salt was added to the top stream to create the desired density difference. The degree of molecular mixing was measured as a function of time by monitoring a diffusion-limited chemical reaction between the two fluid streams. The pH of each stream was modified by the addition of acid or alkali such that a local neutralization reaction occurred as the two fluids molecularly mixed. The progress of this neutralization reaction was tracked by the addition of phenolphthalein - a pH-sensitive chemical indicator - to the acidic stream. Accurately calibrated backlit optical techniques were used to measure the average concentration of the colored chemical indicator. Comparisons of chemical product formation for pre-transitional buoyancy- and shear-driven mixing layers are given. It is also shown that experiments performed at different equivalence ratios (acid/alkali concentration) can be combined to obtain a mathematical relationship between the colored product formed and the density variance. This relationship was used to obtain high-fidelity, quantitative measures of the degree of molecular mixing which are independent of probe resolution constraints. The dependence of such mixing parameters on the Schmidt and Reynolds numbers is examined by comparing the current Sc {approx} 10{sup 3} measurements with Sc = 0.7 gas-phase and Pr = 7 liquid-phase measurements. This comparison indicates that the Schmidt number has a large effect on the bulk quantity of mixed fluid at small Reynolds numbers Re{sub h} < 10{sup 3}. At late times, all mixing parameters indicated a greater degree of molecular mixing and a decreased Schmidt number dependence. Implications for the development and quantitative assessment of turbulent transport and mixing models appropriate for

  13. Incidence of visible and occult blood on laryngoscope blades and handles.

    PubMed

    Phillips, R A; Monaghan, W P

    1997-06-01

    Anesthesia providers must take appropriate precautions to reduce the potential for transmission of infectious agents to the patients under their care. The devastating spread of human immunodeficiency virus (HIV) and hepatitis B virus (HBV) over the past decade has resulted in the development of specific guidelines for the cleaning, disinfection, sterilization, and handling of medical equipment and instruments. Contamination of laryngoscope blades and handles with visible and occult blood frequently occurs during routine airway management. Several studies suggest procedures for cleaning, disinfection, sterilization, or handling of laryngoscope blades and handles are ineffective, or there may be poor compliance with the established protocols. The purpose of this study was to determine the incidence of visible and occult blood on laryngoscope blades and handles that were identified as ready for patient use. Sixty-five laryngoscope blades and handles identified as ready for patient use were observed for visible blood and tested for occult blood. A modified version of the three-stage phenolphthalein blood indicator test was employed to determine the presence of occult blood. None of the blades or handles observed had visible blood. Of the 65 blades tested for occult blood, 13 (20%) tested positive. Of the 65 handles tested for occult blood, 26 (40%) tested positive. More afternoon blades and handles tested positive for occult blood than morning blades and handles (P < 0.01). The extent to which contaminated anesthesia equipment plays in nosocomial infection is difficult to determine. The presence of blood is an indicator of potential cross-infection, since biological fluids, such as blood and saliva, are known to transmit infectious diseases. This study confirms that more rigorous decontamination protocols must be instituted to ensure complete removal of blood prior to sterilization, since laryngoscope blades and handles have irregular surfaces with repositories for

  14. Net alkalinity and net acidity 1: Theoretical considerations

    USGS Publications Warehouse

    Kirby, C.S.; Cravotta, C.A.

    2005-01-01

    Net acidity and net alkalinity are widely used, poorly defined, and commonly misunderstood parameters for the characterization of mine drainage. The authors explain theoretical expressions of 3 types of alkalinity (caustic, phenolphthalein, and total) and acidity (mineral, CO2, and total). Except for rarely-invoked negative alkalinity, theoretically defined total alkalinity is closely analogous to measured alkalinity and presents few practical interpretation problems. Theoretically defined "CO 2-acidity" is closely related to most standard titration methods with an endpoint pH of 8.3 used for determining acidity in mine drainage, but it is unfortunately named because CO2 is intentionally driven off during titration of mine-drainage samples. Using the proton condition/mass- action approach and employing graphs to illustrate speciation with changes in pH, the authors explore the concept of principal components and how to assign acidity contributions to aqueous species commonly present in mine drainage. Acidity is defined in mine drainage based on aqueous speciation at the sample pH and on the capacity of these species to undergo hydrolysis to pH 8.3. Application of this definition shows that the computed acidity in mg L -1 as CaCO3 (based on pH and analytical concentrations of dissolved FeII, FeIII, Mn, and Al in mg L -1):aciditycalculated=50{1000(10-pH)+[2(FeII)+3(FeIII)]/56+2(Mn)/ 55+3(Al)/27}underestimates contributions from HSO4- and H+, but overestimates the acidity due to Fe3+ and Al3+. However, these errors tend to approximately cancel each other. It is demonstrated that "net alkalinity" is a valid mathematical construction based on theoretical definitions of alkalinity and acidity. Further, it is shown that, for most mine-drainage solutions, a useful net alkalinity value can be derived from: (1) alkalinity and acidity values based on aqueous speciation, (2) measured alkalinity minus calculated acidity, or (3) taking the negative of the value obtained in a

  15. Effects of the use of ultrasonic waves on biodiesel production in alkaline transesterification of bleached tallow and vegetable oils: Cavitation model

    NASA Astrophysics Data System (ADS)

    Alape Benitez, Fabio

    Experiments of biodiesel production via methanolysis were performed at methanol/triglyceride molar ratios of 3, 4.5, and 6 and temperatures of 25°C, 40°C and 60°C; the reaction was monitored by HPLC, X-Ray, and GC-MS until equilibrium. A mathematical model called CAVITATION MODEL was developed to deal with mass transfer aspects of the alkaline transesterification reaction of vegetable oils; a comparison between the cavitation model and diffusion through spherical pores was made. Gas-vapor bubble dynamics for the methanol-soybean oil and methanol-tallow system were examined at 40°C and 42°C, respectively. The Rayleight-Plesset equations were used to describe the isothermal growth and adiabatic collapse of the bubble formed when a field of ultrasound at 20 KHz is applied. Temperatures of 2265 K and 426 K were estimated for a bubble in soybean oil-methanol and tallow-methanol systems, respectively. These "Hot Spots" could be responsible for the increment of the temperature occurred and the acoustic streaming observed during the alkaline transesterification reaction. Also, a diffusion analysis with the pore model was made to predict the concentration profile of the triglycerides within the liquid drops of alcohol created after the collapse of the gas-vapor bubbles; spherical shapes were studied. A computational model was made in MathCad to evaluate the effectiveness at different Thiele modulus values in order to estimate mass transfer coefficients for the most critical conditions of pure diffusion and these coefficients were compared with those found by the cavitation model estimation. Pictures of the reactant system soybean oil-methanol-potassium hydroxide, with the red dyed methanol using phenolphthalein, showed that the alkalinity of the system represented by potassium hydroxide remains in the interface alcohol-oil and then is displaced into the glycerol or down layer. The present study serves as a basis for the analysis of heterogeneous reactions with

  16. Adsorption properties of cross-linked cellulose-epichlorohydrin polymers in aqueous solution.

    PubMed

    Udoetok, Inimfon A; Dimmick, Raquel M; Wilson, Lee D; Headley, John V

    2016-01-20

    Cellulose was cross-linked with epichlorohydrin (EP) at variable levels (CLE-0.5, CLE-2 and CLE-4), where CLE-i denotes the cellulose to EP mole ratios. The cross-linked products were characterized by TGA and FT-IR spectroscopy, pH at the point of zero charge (pHpzc), water swelling, and dye-adsorption methods employing two types of dyes [phenolphthalein (phth) and p-nitrophenol (PNP)]. The characterization methods provide evidence of cross-linking of cellulose in accordance with variations in surface area, PZC, available surface hydroxyl groups, and thermal stability when compared against pristine cellulose. The pHpzc of the sorbent materials was ∼ 6.5 indicating a negative surface charge occurs above pHpzc. The cross-linked polymers possess greater swelling properties relative to pristine cellulose. Detailed adsorption studies were carried out at pH 9 for cellulose and CLE-i with five types single component carboxylate anions [2-hexyldecanoic acid (S1), trans-4-pentylcyclohexanecarboxylic acid (S2), 2-dicyclohexylacetic acid (S3), adamantane carboxylic acid (S4), and cyclohexane carboxylic acid (S5)] at 295 K. The uptake properties of PNP with cellulose and CLE-i were also compared at pH 5 and 9, respectively. CLE-2 had the highest uptake of PNP (Qm=1.22 × 10(-1)mmol/g, pH 9) and S1 (Qm=4.27 mg/g) while cellulose and CLE-4 had the strongest binding affinity (1.43 L/mmol and 5.90 × 10(-2)L/mg), respectively. Uptake of PNP by CLE-0.5 at pH 5 (Q m=5.30 × 10(-2)mmol/g) was higher than uptake at pH 9 (Qm=3.11 × 10(-2)mmol/g). Sorption of CLE-4 with S1, S2 and S3 showed that relative uptake of the surrogates had the following order: S3>S2>S1, where S2 had the strongest binding affinity to CLE-i. CLE-2 had the highest sorption capacity towards Si in an equimolar mixture with evidence of molecular selective uptake. At pH 9, low uptake was mainly related to electrostatic repulsion between the negatively charged sorbent surface and the carboxylate head groups of Si.

  17. Self-Irradiation Effects on 99Mo Reagents and Products

    SciTech Connect

    Carson, S.D.; Garcia, M.J.; McDonald, M.J.; Simpson, R.L.; Tallant, D.R.

    1998-10-07

    produced in 1996 and shipped to pharmaceutical houses for evaluation of compatibility with oxime solution used to precipitate `?vfo as the oxime complex is both air and light-sensitive, and containing a black precipitate that forms during shipment, presumably as a result of self- irradiation. Addition of sodium hypochlorite to the product solution prior to shipment prevents precipitate formation, indicating the precipitate is a reduced form of `%lo. to remove any precipitate. Duplicate aliquots of the filtered samples were titrated to a phenolphthalein irradiation and afler standing at room temperature for 86.4 hours. Precipitates were washed to a FTIR analysis of the white precipitate showed it to be alpha benzoin oxime. Since the basic After 86.4 hours, no precipitate had formed in bottles containing sodium hypochlorite. Black precipitate had formed in all bottles that did not contain sodium hypochlorite after 14.4 hours. The precipitate appeared to initially form on the surface of the HDPE sample bottles and Black precipitate was first noticed in sample set 1 after 28.8 hrs' irradiation. No visible sample containing precipitate was kept at room temperature in the original bottle. Precipitate in sample sets 2 and 3. Since no precipitate formed in these bottles, this was equivalent to duplicate samples. Once the precipitate in the 20-mL aliquots that had been set aside had returned to sample sets 1 through 3 and the samples with redissolved precipitate all experienced an average decrease in base strength of 0.013 meq mL-l. Sample 1-C had a decrease of 0.004 meq mL-l and sample 1-D had returned to the initial value of 0.198 meq mL-l. Raman spectra for the black precipitate from samples l-C, 1-D and supplemental sample set 1 Fig. 2. Raman spectra of the black precipitate formed in 9%40 product solutions after 28.8,43.2, 72 and 86.4 hours of `oCo irradiation in Sandia's Gamma Irradiation Facility. increase with time, as seen in the titration of 1-C and 1-D samples

  18. Adsorption properties of cross-linked cellulose-epichlorohydrin polymers in aqueous solution.

    PubMed

    Udoetok, Inimfon A; Dimmick, Raquel M; Wilson, Lee D; Headley, John V

    2016-01-20

    Cellulose was cross-linked with epichlorohydrin (EP) at variable levels (CLE-0.5, CLE-2 and CLE-4), where CLE-i denotes the cellulose to EP mole ratios. The cross-linked products were characterized by TGA and FT-IR spectroscopy, pH at the point of zero charge (pHpzc), water swelling, and dye-adsorption methods employing two types of dyes [phenolphthalein (phth) and p-nitrophenol (PNP)]. The characterization methods provide evidence of cross-linking of cellulose in accordance with variations in surface area, PZC, available surface hydroxyl groups, and thermal stability when compared against pristine cellulose. The pHpzc of the sorbent materials was ∼ 6.5 indicating a negative surface charge occurs above pHpzc. The cross-linked polymers possess greater swelling properties relative to pristine cellulose. Detailed adsorption studies were carried out at pH 9 for cellulose and CLE-i with five types single component carboxylate anions [2-hexyldecanoic acid (S1), trans-4-pentylcyclohexanecarboxylic acid (S2), 2-dicyclohexylacetic acid (S3), adamantane carboxylic acid (S4), and cyclohexane carboxylic acid (S5)] at 295 K. The uptake properties of PNP with cellulose and CLE-i were also compared at pH 5 and 9, respectively. CLE-2 had the highest uptake of PNP (Qm=1.22 × 10(-1)mmol/g, pH 9) and S1 (Qm=4.27 mg/g) while cellulose and CLE-4 had the strongest binding affinity (1.43 L/mmol and 5.90 × 10(-2)L/mg), respectively. Uptake of PNP by CLE-0.5 at pH 5 (Q m=5.30 × 10(-2)mmol/g) was higher than uptake at pH 9 (Qm=3.11 × 10(-2)mmol/g). Sorption of CLE-4 with S1, S2 and S3 showed that relative uptake of the surrogates had the following order: S3>S2>S1, where S2 had the strongest binding affinity to CLE-i. CLE-2 had the highest sorption capacity towards Si in an equimolar mixture with evidence of molecular selective uptake. At pH 9, low uptake was mainly related to electrostatic repulsion between the negatively charged sorbent surface and the carboxylate head groups of Si

  19. Improved water and sodium absorption from oral rehydration solutions based on rice syrup in a rat model of osmotic diarrhea.

    PubMed

    Wapnir, R A; Litov, R E; Zdanowicz, M M; Lifshitz, F

    1991-04-01

    Rice syrup solids, rice protein, and casein hydrolysate were added to experimental oral rehydration solutions in various combinations and tested in a rat intestinal perfusion system. Chronic osmotic diarrhea was induced in juvenile rats by supplying the cathartic agents, magnesium citrate and phenolphthalein, in their drinking water for 1 week. The experimental oral rehydration solutions were compared with standard oral rehydration solutions containing 20 gm/L or 30 gm/L of glucose and with each other to determine if there were significant differences in net water, sodium, or potassium absorption. An oral rehydration solution containing 30 gm/L of rice syrup solids had a net water absorption rate significantly higher than that of the standard 20 gm/L glucose-based oral rehydration solution (2.1 +/- 0.62 versus 1.5 +/- 0.48 microliters/[min x cm], p less than 0.05). Casein hydrolysate did not significantly affect net water absorption. However, combinations of 30 gm/L rice syrup solids and 5 gm/L casein hydrolysate significantly increased (p less than 0.05) net sodium and potassium absorption compared with the 20 gm/L glucose-based oral rehydration solution but not versus rice syrup solids alone. Oral rehydration solutions containing 30 gm/L rice syrup solids plus 5 gm/L rice protein, and 30 gm/L rice syrup solids plus 5 gm/L casein hydrolysate, had net water absorption rates significantly higher than the rate of a 30 gm/L glucose-based oral rehydration solution (2.5 +/- 0.36 and 2.4 +/- 0.38, respectively, versus 0.87 +/- 0.40 microliters/[min x cm], p less than 0.05). Rice protein and casein hydrolysate, however, did not significantly affect net water, sodium, or potassium absorption when added to rice protein glucose-based oral rehydration solutions. An inverse correlation between osmolality and net water absorption was observed (r = -0.653, p less than 0.02). The data suggest that substitution of rice syrup solids for glucose in oral rehydration solutions will

  20. Ovariectomized mouse uterotrophic assay of 36 chemicals.

    PubMed

    Ohta, Ryo; Takagi, Atsuya; Ohmukai, Hideo; Marumo, Hideki; Ono, Atsushi; Matsushima, Yuko; Inoue, Tohru; Ono, Hiroshi; Kanno, Jun

    2012-01-01

    The concern over endocrine disruptors prompted international establishment of a strategic framework for the identification of the estrogenic compounds. OECD has launched the Conceptual Framework tool box containing various screening and testing methods including the uterotrophic assay. The (anti)estrogenicity of 36 chemicals suspected to be estrogen-receptor interactive by in silico and/or in vitro screening in the Extended Scheme for Endocrine Disruptor Screening and Testing of the Ministry of Health, Labour and Welfare, Japan, were monitored by the uterotrophic assay using C57BL/6J ovariectomized adult female mice after a 7-day exposure by oral gavage (po) and subcutaneous injection (sc). Ethynyl estradiol was used as reference for agonist and antagonist detection. In addition, Bisphenol A (sc) and Genistein (po) were tested for the comparison to rat assays. Among the 36, 2-[Bis(4-hydroxy-phenyl)methyl]benzylalcohol, 2,2',4,4'-Tetrahydroxybenzophenone, 2,4-Dihydroxybenzophenone, 3,3',5-Triiodothyroacetic acid, New fuchsin and alpha-Naphtholbenzein, showed both estrogenic agonistic and antagonistic activities; first two showed U-shaped dose-response in antagonistic studies. N,N-Diphenyl-p-phenylenediamine, 2,2'-Dihydroxy-4,4'-dimethoxybenzophenone, n-Butyl 4-hydroxybenzoate, and Reserpine were agonistic by sc. Benzo [a] pyrene, Benz [a] anthracene, Dibenz [a,h] anthracene, 2-(2H-Benzotriazol-2-yl)-4,6-di(t-pentyl)phenol, Rosemarinic acid, meta-Thymol, 6-Gingerol, Colchicine, Malachite green base, Fenbuconazole, and Lead acetate were antagonistic. The rest, i.e. n-Heptyl 4-hydroxybenzoate, Tetrazolium violet, Pravastatin sodium salt, Physostigmine, salicylate (1:1), Nordihydroguaiaretic acid, o-Cresolphthalein, 1,3-Dinitrobenzene, C.I. Pigment orange, Tetrabromobis-phenol-A, 2-Hydroxy-4-methoxybenzophenone, Ethylparaben, Propyl p-hydroxybenzoate, Kaempferol, 2-(2-Benzotriazolyl)-p-cresol and Phenolphthalein were negative for both effects. Taking together with in

  1. ORGANIC MATTER IN THE EXPIRED BREATH WITH ESPECIAL REFERENCE TO ITS INHIBITING POWER ON OXIDIZING FERMENTS.

    PubMed

    Amoss, H L

    1913-02-01

    substances which he claims inhibit the oxidation of guaiacum by blood. His results are therefore inconclusive. The phenolphthalin test for blood has been studied in this connection and further light has been thrown on this reaction. The sodium salt of phenolphthalin is colorless in alkaline solution, and is readily oxidized by minute quantities of blood to phenolphthalein which gives a characteristic deep purplish red color in alkaline solution. It has been found that the presence of calcium chloride and ammonium chloride in small amounts retards and, in large amounts, prevents this reaction. It is believed that any salt composed of a weak base combined with a strong acid will have the same effect. This is discussed in the text. It has also been shown that the presence of calcium chloride or ammonium chloride decreases the depth of color of phenolphthalein in sodium hydroxide solution. Carbon dioxide also prevents the oxidation of phenolphthalin by blood. Of course this does not mean that carbon dioxide prevents the action of the oxidizing ferments generally. In this particular case the substance to be oxidized, namely phenolphthalin, was not allowed by reason of the presence of the carbon dioxide to combine with the alkali and thereby assume a state in which it could be easily oxidized. The results of one experiment seem to indicate a relation between the amount of dissolved oxygen in the solutions and the percentage of oxidation. Sodium chloride either alone or with the aid of hydrogen peroxide is able to bring about the oxidation of phenolphthalin in alkali to a very slight extent (3.5 to 5 per cent. in twenty-four hours). Therefore phenolphthalin as a test for oxidizing ferments should not be used in the presence of an appreciable amount of inorganic salts or carbon dioxide. Complete dialysis is recommended in these cases. It is also to be noted that the great delicacy of the test allows considerable dilution. Liquids were obtained from the expired breath by passing this

  2. Separation of acid phosphatases in the rat ventral prostate by gel filtration, isoelectric focusing, and chromatofocusing.

    PubMed

    Jauhiainen, A; Rytöluoto-Kärkkäinen, R; Vanha-Perttula, T

    1983-01-01

    Acid phosphatases of the rat ventral prostate were fractionated by gel filtration (GF) on Sepharose 6B, isoelectric focusing (IEF), and chromatofocusing (CF). In GF three activity peaks (GF-1, GF-2, GF-3) were disclosed. They showed some differences in substrate preference when six substrates (p-nitrophenyl phosphate; p-NPP; phenolphthalein phosphate, Phe-P; thymolphthalein phosphate, Tym-P; alpha-naphthyl phosphate, alpha-NP; beta-naphthyl phosphate, beta-NP; naphthol ASBI phosphate, N-ASBI-P) were tested. Differences were also encountered in their sensitivity to tartrate and fluoride. IEF gave seven bands at different pI values (8.3, 8.1, 7.9, 7.1, 6.4, 5.5, and 5.0) with alpha-NP and beta-NP but only four with N-ASBI-P. Four of the bands (8.3, 8.1, 7.9, 5.5) were sensitive to tartrate. In CF eight activity peaks (CF-1 to CF-8) were resolved with the six substrates. They differed from each other in pI values, pH optima, substrate preference, and modifier characteristics. Peaks CF-1 (pI 8.3, pH 5.5), CF-2 (pI 8.1, pH 4.2) and CF-3 (pI 7.9, pH 4.2) had a large substrate spectrum and high sensitivity to tartrate and fluoride. CF-4 (pI 7.1, pH 6.0) and CF-7 (pI 5.5, pH 4.2) were low in activity, preferred alpha-NP as substrate, and were moderately sensitive to tartrate. CF-5 (pI 6.4, pH 5.5) and CF-8 (pI 5.0, pH 5.0) were able to hydrolyse all substrates tested with moderate inhibition by tartrate. CF-6 (pI 6.0, pH 5.0) showed a relative preference for p-NPP and Phe-P with no hydrolysis of N-ASBI-P and Tym-P. Of these activities CF-6 and CF-7 were also clearly activated by Co2+. Peaks CF-6 and CF-7 appeared the most sensitive to p-chloromercuribenzoate. It is concluded that activities CF-1, CF-2, and CF-3 are lysosomal isoenzymes with minor structural differences. The others are possibly all nonlysosomal with greater biochemical differences. Some of them apparently represent the secretory form(s) of acid phosphatase in the rat ventral prostate.