摘要:

AbstractA rapid and sensitive isocratic technique is described for the determination of concentrations of adriamycin and two of its metabolites, adriamycinol and adriamycinone, in freshly isolated rat hepatocytes. The drugs are easily and efficiently extracted from the cells with an organic mixture (chloroform–n‐butanol) after proteolytic digestion with trypsin. Mean recoveries from spiked culture medium cell suspension are greater than 96%. The within run and day‐to‐day coefficients of variation are less th

ISSN:0269-3879    

DOI:10.1002/bmc.1130020302

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractGalactose in plasma from patients with hepatic diseases who had undergone low level galactose infusion was determined by using HPLC with electrochemical detection (LCEC). Agreement between galactose concentration determined by the LCEC and a fluorometric method was remarkably good at moderate levels of galactose in plasma. However, the fluorometric method is not suitable for samples containing very small amounts of galactose (blood from hepatic veins) and even for a few samples at moderate galactose content (blood from peripheral veins), suggesting the presence of an endogenous interference. There was no interference for the quantitation of galactose by the LCEC method, by virtue both of the specificity involved in the electrochemical detection and the separation by liquid chromatography. The detection limit of the LCEC method was 0.4 mg galactose/L blood.

ISSN:0269-3879    

DOI:10.1002/bmc.1130020303

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractIt has been shown that by electrochemical oxidation 7‐nitrobenzo‐2‐oxa‐1,3‐diazole‐tryptochan (NBD‐T) is converted to fluorophores having the same emission and excitation spectra as those for other NBD‐amino acids, NBD‐dioxindolylalanine was tentatively assumed to be a main electrochemical oxidation product of NBD‐tryptophan. A coulochemical cell placed between an analytical column and a fluorometer showed no detrimental effect on the separation of NBD‐amino acids by reversed phase HPLC. Highly sensitive fluorescence detection was achieved for amino and imino acids at 10–100 fmol levels. The detection limit for

ISSN:0269-3879    

DOI:10.1002/bmc.1130020304

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractManual integration of the amino acid peaks from physiological samples produced by conventional anion exchange liquid chromatography is a time‐consuming process. This paper describes a combined unit, consisting of an analog to digital converter and a personal computer, which was connected in parallel with the chart recorder and the analyser's 570 nm channel of the colorimeter. The computer was programmed to log the digitized data, detect the start, maximum and end of each chromatographic peak, calculate the area under the peak and its retention time and provide a printoct of the results at the end of the elution program. The computer program successfully exploited the Trigg Tracking Signal as both a peak detection and as a moving baseline monitoring device. This approach proved to have an equivalent performance to the manual method for 17 out of the 19 amino acids normally quantitated in physiological samples. The automated detection and quantitation of arginine was unsatisfactory due to its characteristically low profile peak shape, and proline was not measured because the device was not connected to the 440 nm channel of the colorimeter. The automated system provided economic and analytically acceptable solutions to the problem of providing an online integrator versatile enough to be used with the 255 min long amino acid analysis of physiological fluid

ISSN:0269-3879    

DOI:10.1002/bmc.1130020305

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractWe have developed a rapid method for the separation of plasma free fatty acids as their phenacyl esters by high‐performance liquid chromatography (HPLC) using a reversed‐phase (C18) column. The derivatives of series of both saturated and unsaturated fatty acids (C12:0C22:6) are simultaneously separated within 45 min and detected with ultraviolet at 241 nm. The limit of detection of fatty acids was approximately 0.5 nmol in 20 μL injected volume of extracts, and the coefficient of variation of the present method did not exceed 3.0%. Comparison of the results of the present HPLC method with those of gas chromatography, gave very good correlations for all fatty acids in human

ISSN:0269-3879    

DOI:10.1002/bmc.1130020306

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractA method for the simultaneous measurement of vanillylmandelic acid, homovanillic acid and 5‐hydroxyindoleacetic acid in urine is described. Based on reversed‐phase liquid chromatography with electrochemical detection, the procedure employs isocratic elution, thus making it suitable for use in the less well‐equipped clinical or research laboratory. A simple extraction of the acids from acidified urine into ethyl acetate, is followed by evaporating to dryness a portion of the organic layer, and redissolving the residue in chromatographic mobile phase. Up to 20 samples can be analysed in a single working day. The method is validated and the results obtained are compared with refereènce methods. The cause of contamination of the glassy carbon surface of the working electrode is investigated, and a simple electrochemical pretreatment is described that overcomes this problem. Finally, the extra clinical information that can be derived from multi‐metabolite assays is co

ISSN:0269-3879    

DOI:10.1002/bmc.1130020307

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractRats, germfree and conventional, were dosed with14C‐labelled benzo[a]pyrene. Faeces and urine were collected. Metabolites in faces were effectively extracted with a new method using a combination of solvents and solid sorbents. Metabolites in urine were extracted with octadecylsilane‐bonded silica. The metabolites were fractionated into groups by chromatography on a cation exchanger (SP‐LH‐20 or SP‐Sephadex C‐25) and an anion exchanger (TEAP‐LH‐20). Some of the groups were further purified by column chromatography and analysed by HPLC and TLC. The analyses show a complex pattern of metabolism. A large part of the metabolites (9–24% depending on animal type and route of excretion) had amphoteric properties, e.g. like glutathione and cysteine conjugates. The abundance of conjugates sensitive to β‐glucuronidase and sulphatase was low. The relative amount of acidic conjugates in faeces was much higher in the germfree than in the conventional rats indicating the influence of the intestinal flora on the metabolism. The results support the view that the mercapturic acid pathway is a quantitatively important metabolic route for benzo[a]pyrene in rats. The methods of extraction and group fractionation were designed to be generally applicable to the analysis of lipophilic xenobiotics a

ISSN:0269-3879    

DOI:10.1002/bmc.1130020308

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractMetoclopramide extracted from plasma and urine has been analysed using reversed phase HPLC with acetic acid/acetonitrile/triethylamine as eluent and fluorescence detection. This method exploits the natural fluorescence of metoclopramide for its detection in patients on multiple drug therapies.

ISSN:0269-3879    

DOI:10.1002/bmc.1130020309

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractA new method for the determination of 5,5‐dimethyl‐2,4‐oxazolidynedione (DMO) in rabbit serum by reversed phase‐HPLC with UV detection is described. The determination of DMO is performed without derivatisation. The internal standard is 5,5‐diethylbarbituric acid (barbital). The method is rapid and simple with sensitivity limit of 20 ng/mL, high recovery (above 92%) and is suitable for pharmacokineti

ISSN:0269-3879    

DOI:10.1002/bmc.1130020310

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

ISSN:0269-3879    

DOI:10.1002/bmc.1130020301

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY