摘要:

AbstractStatic ammonia etching has been used to effect regular surface roughening of glass capillaries. Following such treatment, polar phases could be coated after persilylation with varioussilylation agents such as hexamethyl‐, tetramethyldiphenyl‐, and tetra‐ phenyldimethyldisilazane, respectively. This method produces columns of high thermostability, which is limited only by the maximum applicable temperature for the phase i

ISSN:0935-6304    

DOI:10.1002/jhrc.1240040902

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractThis work describes the use of glass capillary columns (GCC) in the rapid concurrent analysis of primary prostaglandins (PGs) (e. g. PGE2, PGE2, PGF2α) and other functionally significant metabolites of arachidonic acid (AA) such as TXB2and 6‐keto PGF1α. The use of a new multistep mixed derivatization approach that generates the methyl esters ofn‐butylboronate, pentafluorobenzyloxime, trimethylsilyl ether derivatives of these compounds remarkably simplifies the GC profiling of the three main pathways of AA metabolism (PGs, thromboxane, and prostacyclin). Furthermore, isomeric species giving very similar or identical mass spectral patterns can be easily identified by their relative retention times on high efficiency capillary co

ISSN:0935-6304    

DOI:10.1002/jhrc.1240040903

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractThe liquid chromatographic separation of some biogenic amines and their metabolites with a reversed‐phase ion‐pair system has been optimized. The effects of the nature of the stationary phase, the column temperature, the pH, and the ion‐pair reagent concentration of the mobile phase have been investigated. The most striking result is the influence of the column temperature on select

ISSN:0935-6304    

DOI:10.1002/jhrc.1240040904

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractThis paper describes the screening for metabolites of butoprozine, a new anti‐anginal drug, in dog bile by means of reverse‐phase HPLC. Although it does involve a simple clean‐up step to remove a substantial amount of endogenous bile compounds, this screening method nevertheless avoids extraction of metabolites and thus allows all metabolites to be introduced into the chromatographic system. A single run of 100 minutes from 100% water to 100% methanol in a linear gradient effects adequate separation of the great majority of metabolites without interference from remaining endogenous compounds.Two methods of differentiating between metabolite peaks and endogenous peaks have been worked out. The first one makes use of14C‐labeled butoprozine by measuring the amount of radioactivity in the column effluent while simultaneously recording the UV absorbance. The second method compares continuous gradient chromatograms of bile recorded before and after butoprozine administration under very similar conditions. The latter method can be applied to both radioactive and non‐radioactive

ISSN:0935-6304    

DOI:10.1002/jhrc.1240040905

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractThe utility ofRekker'shydrophobic fragmental constant has been examined for optimization of reversed‐phase mode liquid chromatographic separations. The chromatographic behavior of about 60 non‐ionic compounds was measured in different acetonitrile/water mixtures and the logarithm of their capacity factors (log k) was correlated with their calculated hydrophobicities (log P). Linear relations were found in each case between log k and log P. The slope of the various lines was related to the percentage concentration of acetonitrile in the mobile phase. It was shown that, by using nine stand ard compounds and measuring their capacity factors in five eluents with different acetonitrile concentrations, the retention time could be predicted for 60 compounds. Calculation of the concentration of the organic modifier was also possible in a system of well coated octadecyl bonded packings with acetonitrile/water mixtures as eluent. Prediction of the capacity factor was accomplished to within 5% er

ISSN:0935-6304    

DOI:10.1002/jhrc.1240040906

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240040907

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240040908

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240040909

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240040910

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240040911

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY