H. Tominaga, M. Ishiyama, Fumio Ohseto, K. Sasamoto, T. Hamamoto, Keiji Suzuki, M. Watanabe
{"title":"A water-soluble tetrazolium salt useful for colorimetric cell viability assay","authors":"H. Tominaga, M. Ishiyama, Fumio Ohseto, K. Sasamoto, T. Hamamoto, Keiji Suzuki, M. Watanabe","doi":"10.1039/A809656B","DOIUrl":"https://doi.org/10.1039/A809656B","url":null,"abstract":"The application of a tetrazolium salt, 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H tetrazolium, monosodium salt (WST-8), to cell viability assays and in vitro drug sensitivity tests is described. With a higher sensitivity as a chromogenic indicator for cell viability compared with conventional tetrazolium salts, WST-8 produced results of cell viability and IC50 values that were in good agreement, respectively, with the MTT method and [3H]thymidine uptake method.","PeriodicalId":7814,"journal":{"name":"Analytical Communications","volume":"53 1","pages":"47-50"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72680878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Rapid multi-component detection of fluorinated drug metabolites in whole urine from a ‘cassette’ dose study using high resolution 19F NMR spectroscopy","authors":"O. Corcoran, J. Nicholson, I. Wilson","doi":"10.1039/A902513H","DOIUrl":"https://doi.org/10.1039/A902513H","url":null,"abstract":"High resolution 19F NMR spectroscopy has been successfully applied to the analysis of drug metabolites in whole rat urine from a ‘cassette’ dose study of 6 fluorinated test compounds dosed at 10 mg kg–1 per compound. A total of 21 compound-related molecules were rapidly detected in the 0–8 h urine samples. The metabolic fate of the compounds after cassette administration appeared to be the same as when the compounds were dosed individually. 19F NMR may thus enable metabolism to be estimated for several compounds simultaneously, with minimal sample preparation, and without interference from endogenous molecules in the biofluid. This analytical approach may therefore be of value at the drug discovery stage in the development of ‘high throughput’ in vivo metabolic screens.","PeriodicalId":7814,"journal":{"name":"Analytical Communications","volume":"45 1","pages":"259-261"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74938820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Electrospray mass spectrometric determination of polycyclic aromatic hydrocarbons by detecting the π–π complexes with tropylium cation","authors":"H. Moriwaki, Akira Imaeda, R. Arakawa","doi":"10.1039/A809573F","DOIUrl":"https://doi.org/10.1039/A809573F","url":null,"abstract":"A method is presented for the determination of polycyclic aromatic hydrocarbons (PAHs) by detecting the PAH–tropylium (π donor–π acceptor) complexes using liquid chromatography-electrospray ionization-mass spectrometry. The complexes were formed by mixing with the tropylium cation after the separation of PAHs through reversed phase liquid chromatography. The detection limits, defined as three times the noise, in the selected-ion monitoring mode were 25–165 ng of the injected PAHs.","PeriodicalId":7814,"journal":{"name":"Analytical Communications","volume":"39 1","pages":"53-56"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75633924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mixed-mode capillary electrochromatographic separation of anionic analytes","authors":"E. Hilder, M. Macka, P. Haddad","doi":"10.1039/A904506F","DOIUrl":"https://doi.org/10.1039/A904506F","url":null,"abstract":"In this work, mixed-mode capillary electrochromatography is introduced as a method for selectivity manipulation in the separation of charged analytes and is investigated for a number of analytes. This concept involves utilising a component of the eluent to permit the chromatographic and capillary electrophoresis (CE) separation mechanisms to contribute in varying proportions to the separation. This approach was first investigated using a combination of CE with reversed-phase liquid chromatography (RP-LC) for hydrophobic, charged analytes (aliphatic sulfonates), and using the concentration of organic modifier in the eluent to control the contributions of CE and RP-LC. However, the use of reversed-phase columns was found to be problematic for mobile phases with less then 50% organic modifier due to the hydrophobicity of the stationary phase causing the column bed to overheat and dry, and low electroosmotic flow (EOF) values (µ ⩽ 17.8 × 10–9 m2 V–1 s–1) caused additional restrictions. In a second case, ion-exchange stationary phases were used, with the type and concentration of a competing anion in the eluent being used to control the contributions of ion chromatography (IC) and CE to the separation. Nine common inorganic anions were separated using a silica based anion-exchange column and phosphate (pH 7.20) or sulfate (pH 8.2) as eluent with direct UV detection at 214 nm and 17 inorganic and small organic anions were separated using a nitrate eluent (pH 6.80) with indirect UV detection at 214 nm. The separation selectivity was shown to be a combination of IC and CE.","PeriodicalId":7814,"journal":{"name":"Analytical Communications","volume":"1 1","pages":"299-303"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73776847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Kotrebai, J. Tyson, P. Udén, M. Birringer, E. Block
{"title":"Identification of the principal selenium compounds in selenium-enriched natural sample extracts by ion-pair liquid chromatography with inductively coupled plasma- and electrospray ionization-mass spectrometric detection","authors":"M. Kotrebai, J. Tyson, P. Udén, M. Birringer, E. Block","doi":"10.1039/A902770J","DOIUrl":"https://doi.org/10.1039/A902770J","url":null,"abstract":"Selenium-enriched garlic and yeast sample extracts and digests were analyzed using ion-pair high performance liquid chromatography (HPLC) with on-line inductively coupled plasma-mass spectrometric (ICP-MS) and electrospray ionization-mass spectrometric (ESI-MS) detection. The principal selenium compounds in these samples were identified as selenomethionine, and Se-adenosyl-selenohomocysteine in yeast, and γ-glutamyl-Se-methyl-selenocysteine and possibly γ-glutamyl-selenomethionine in garlic. The compounds identified account for 85 and 90% of the total selenium content of the yeast and the garlic samples, respectively. On-line HPLC-ESI-MS selected ion chromatograms (SIC) and mass spectra of selenium compounds extracted from selenium enriched samples are presented. Limits of quantification (LOQ, defined as S/N = 10) for HPLC-ICP-MS were in the range 10–50 ng mL–1 Se in the injected extracts. LOQ values for HPLC-ESI-MS were ca. 100 times higher than those of HPLC-ICP-MS.","PeriodicalId":7814,"journal":{"name":"Analytical Communications","volume":"48 1","pages":"249-252"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74020385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Determination of α,4-dihydroxy-3-methoxybenzeneacetic acid (vanilmandelic acid) by flow injection analysis coupled with luminol–hexacyanoferrate(III) chemiluminescence detection","authors":"N. W. Barnett, P. S. Francis, S. Lewis, K. Lim","doi":"10.1039/A900927B","DOIUrl":"https://doi.org/10.1039/A900927B","url":null,"abstract":"A simple and robust method for the determination of the clinically significant molecule vanilmandelic acid (α,4-dihydroxy-3-methoxybenzeneacetic acid, 4-hydroxy-3-methoxymandelic acid) using flow injection analysis with chemiluminescence detection is described. This compound was found to enhance the chemiluminescence from the reaction of luminol with hexacyanoferrate(III) in a basic medium. The calibration function obtained over the range from 2.5 × 10–8 to 1.0 × 10–6 mol dm–3 approximated to linearity (r2 = 0.9995) with the equation of best fit of y = 1.72 × 108x + 36.9, where y is the integrated signal (V s) and x is the concentration (mol dm–3). Precision (as measured by relative standard deviation) was 2.6% for 5 replicate analyses of a standard (2.5 × 10–7 mol dm–3) and the limit of detection (3σ) was 2 × 10–8 mol dm–3. Preliminary investigations revealed that the structurally similar homovanillic acid inhibits the emission of chemiluminescence from the luminol–hexacyanoferrate(III) reaction and that the kinetics of light emission were different from those of the vanilmandelic acid enhanced reaction.","PeriodicalId":7814,"journal":{"name":"Analytical Communications","volume":"15 1","pages":"131-134"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72814491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Creaser, D. Weston, J. Wilkins, Clare P. Yorke, J. A. Irwin, B. Smith
{"title":"Determination of benzene in aqueous samples by membrane inlet, solid phase microextraction and purge and trap extraction with isotope dilution gas chromatography-mass spectrometry","authors":"C. Creaser, D. Weston, J. Wilkins, Clare P. Yorke, J. A. Irwin, B. Smith","doi":"10.1039/A908037F","DOIUrl":"https://doi.org/10.1039/A908037F","url":null,"abstract":"The determination of benzene in aqueous samples is reported using membrane inlet, solid phase microextraction and purge and trap extraction techniques combined with gas chromatography-mass spectrometry. The membrane inlet and solid phase microextraction techniques have been applied to the analysis of soft drink samples and the performance characteristics of these methods compared to the established purge and trap method. Isotope dilution quantitative procedures with hexadeuterobenzene as internal standard were used in combination with all three sampling inlets. Detection limits were at, or below the parts per billion (µg l–1) level with analytical precision (%RSD) in the range 3–8%.","PeriodicalId":7814,"journal":{"name":"Analytical Communications","volume":"27 1","pages":"383-386"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73735257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Electroanalysis of melatonin using castor oil–graphite paste electrode","authors":"A. Radi","doi":"10.1039/A809906E","DOIUrl":"https://doi.org/10.1039/A809906E","url":null,"abstract":"A carbon paste electrode containing castor oil as a binder was prepared and the preconcentration of melatonin at this electrode was examined. Melatonin proved to be readily extracted into castor oil, thus allowing its sensitive determination by extractive stripping voltammetry. The response was evaluated with respect to pH, preconcentration time, reproducibility and other variables. Under optimal conditions, a detection limit of 1 × 10–9 mol dm–3 was obtained and the calibration curve was linear over the range 5 × 10–8–1 × 10–7 mol dm–3. Applying the medium-exchange approach enhanced the selectivity of determination. A simple procedure was developed for the voltammetric determination of melatonin in serum samples.","PeriodicalId":7814,"journal":{"name":"Analytical Communications","volume":"16 1","pages":"43-44"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80158079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Influence of sugar moiety of ovoglycoprotein on chiral discrimination","authors":"J. Haginaka, H. Matsunaga","doi":"10.1039/A808472F","DOIUrl":"https://doi.org/10.1039/A808472F","url":null,"abstract":"The influence of sugar moieties of ovoglycoprotein from chicken egg whites (OGCHI) on chiral discrimination of various solutes has been investigated. Partially deglycosylated OGCHI and completely deglycosylated OGCHI were obtained by treatment of OGCHI with N-glycosidase, and endoglycosidase and N-glycosidase, respectively. The average molecular weights of OGCHI, partially deglycosylated OGCHI and completely deglycosylated OGCHI were estimated to be about 30 400, 28 200 and 21 700, respectively, by matrix-assisted laser desorption time-of-flight mass spectrometry. It was found that partially deglycosylated OGCHI showed excellent chiral recognition abilities comparable to OGCHI, and that completely deglycosylated OGCHI still showed chiral recognition abilities for various solutes tested. These results reveal that the chiral recognition site(s) for OGCHI is present on the protein domain of OGCHI.","PeriodicalId":7814,"journal":{"name":"Analytical Communications","volume":"48 1","pages":"39-41"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80289945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Ludlow, D. Louden, A. Taylor, B. Wright, I. Wilson
{"title":"Size exclusion chromatography with UV detection coupled to on-line 1H-NMR and on-line collection via a dedicated interface for subsequent off-line FT-IR","authors":"M. Ludlow, D. Louden, A. Taylor, B. Wright, I. Wilson","doi":"10.1039/A900602H","DOIUrl":"https://doi.org/10.1039/A900602H","url":null,"abstract":"The coupling of size exclusion chromatography (SEC) to on-line NMR spectroscopy and a dedicated interface for the collection of the chromatographic eluent for subsequent FT-IR has been investigated using a number of polymer additives as model compounds. SEC was performed using deuterated chloroform as eluent with the separation monitored on-line by UV detection at 254 nm and on-flow 1H-NMR. The effluent from the NMR probe was directed to a dedicated HPLC/FT-IR interface where it was deposited on a germanium plate. FT-NMR and FT-IR spectra were successfully obtained for 2,6-di-tert-butyl-4-methylphenol (BHT), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (Irganox 1076) and di-iso-octylphthalate.","PeriodicalId":7814,"journal":{"name":"Analytical Communications","volume":"3 1","pages":"85-87"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78416018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}