摘要:

The behavior of acids on the layers of cellulose and silica gel was studied. The samples used were HCl and HClO4, and the developers were water, acetone, ethanol, and n-butanol. Monitored, was also the behavior of HCl as a component of the developers water-HCl and n-butanol-HCl. The results have shown that acids are strongly sorbed on the layers of silica gel and cellulose. Hydrogen ion and an anion of strong inorganic acids behaved differently on sorbent layer; generally H+ion was stronger sorbed than A−ion. Sorption and behavior of acid ions depended on the properties of a sorbent, solvent and acid, i. e. on an interaction of all components of the chromatographic system.

ISSN:1082-6076    

DOI:10.1081/JLC-100101767

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Chiral stationary phases based on tris-3,5-dimethyl-phenylcarbamate derivatives of cellulose and amylose were used for the resolution of some chiral drugs and their metabolites. The Chiralcel OD-H and Chiralpak AD columns were employed under normal phase conditions using hexane/ethanol or hexane/2-propanol as the mobile phases. The influence of trace amounts of diethylamine in the mobile phase was also evaluated. The Chiralcel OD-R column was employed under reversed phase condition using mainly perchlorate solution supplemented with acetonitrile.

ISSN:1082-6076    

DOI:10.1081/JLC-100101768

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Assays of adenosine and its derivatives in biological fluids involve fluorimetric, radioimmunological or chromatographic analyses. Techniques currently used are tedious because they involve either an extraction using immunological methods or one or two freeze drying cycles when using high performance liquid chromatography (HPLC). In this context, we describe a “quick” HPLC method using a diode array detector for the spectral analysis and quantitation of adenosine and its derivatives in less than two hours following sampling. We compared our results to those obtained with an HPLC technique coupled to UV detection.

ISSN:1082-6076    

DOI:10.1081/JLC-100101769

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The concentrations ofcisandtrans-polydatin (resveratrol 3-β-glucoside) were measured in 133 red wines by two methods: Method A utilized normal phase HPLC with isocratic elution followed by UV detection, and Method B was based on reverse phase HPLC with gradient elution and photodiode array detection. In each method, 20 μL of sample was directly injected without prior treatment.

ISSN:1082-6076    

DOI:10.1081/JLC-100101770

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A fast and sensitive reverse phase HPLC-UV method for the separation and quantitation of haloperidol and its related compound 4,4′-Bis[4-(p-chlorophenyl)-4-hydroxypiperidino] bu-tyrophenone} in both drug substance and tablet dosage form is reported. A non-porous silica (NPS) ODS-1 column was used as the stationary phase and the mobile phase consisted of 77:23 v/v 50 mM phosphate buffer with 0.2% triethylamine (TEA) pH 2.5/acetonitrile. The flow rate was 1.0 mL/min with detection at 220 nm.

ISSN:1082-6076    

DOI:10.1081/JLC-100101771

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A Reversed-Phase High Performance Liquid Chromatographic (RP-HPLC) method for simultaneous and separate determination of cis and trans-permethrin and piperonyl butoxide in a shampoo formulation is described and fully validated. This method entails the quantification of both components by external standard and ultraviolet detection at two wavelengths (201 and 287nm). A C8 Lichrosorb column and a three component mobile phase, isocratically delivered was used.

ISSN:1082-6076    

DOI:10.1081/JLC-100101772

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A chiral high performance liquid chromatography method was developed for the resolution of the enantiomers of two new β-aminoalcohols, isamoltane and enciprazine. The separation of the enantiomers was accomplished, without any derivatization, on a chiral column containing 3,5-dimethylphenylcarbamate of cellulose (Chiralcel OD) as chiral selector.

ISSN:1082-6076    

DOI:10.1081/JLC-100101773

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A High Performance Liquid Chromatographic (HPLC) method was developed for the analysis of Bay 12-9566 (4-[4-4-(chlorophenyl)Phenyl]-4-oxo-2S-(phenylthiomethyl) butanoic acid), a metalloproteinase inhibitor, and its three metabolites, M1 (sulfoxide), M2 (ρ-hydroxy) and M3 (reduction product) in plasma. Sample preparation involved precipitation of plasma proteins using acidified acetonitrile. A reverse phase chromatography with gradient elution, ultraviolet detection at 290 nm and internal standard were used for separation and quantitation of all analytes. The quantitation range was 0.10 μg/mL to 50 μg/mL for BAY 12-9566, and 0.10 μg/mL to 3.00 μg/mL for all three metabolites. The limit of detection for BAY 12-9566 and for all three metabolites was 0.05 μg/mL. Intra-day accuracy for BAY 12-9566 and the three metabolites ranged from 95.0 to 105.0% and precision (CV) ranged from 0.0 to 4.76%.

ISSN:1082-6076    

DOI:10.1081/JLC-100101774

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A binary gradient HPLC assay was developed for the separation and quantitation of carbamazepine (CBZ),carbamazepine-epoxide (CBZ-ep), carbamazepine-10,11-trans-diol (CBZ-diol), carbamazepine-2-hydroxide (CBZ-OH),carbamazepine-3-hydroxide (CBZ-3OH) and carbamazepine-acridan (CBZ-acr) extracted from patient urine. The internal standard was 10-methoxy-carbamazepine. The initial phase was 70:15:15 phosphate buffer-methanol-acetonitrile followed by a linear gradient commencing at 13 minutes to 50:35:15 phosphate buffer-methanol-acetonitrile at 24 minutes. The flow rate was constant at 2 mL/min. The UV absorbance detector wavelength was changed at 18 minutes from 240 nm to 280 nm. Typical retention times for CBZ-diol, CBZ-2OH, CBZ-ep, CBZ-3OH, CBZ-acr, CBZ and internal standard were 5.26, 8.36, 10.46,12.51,14.2, 23 and 27.53 minutes respectively. The minimum quantifiable limit (MQL) for all of the analytes was 0.2 μg/mL except for CBZ-2OH where the MQL was 2 μg/mL. Precision and accuracy of the assay was 1.3 to 19.4% for the 6 analytes.

ISSN:1082-6076    

DOI:10.1081/JLC-100101775

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A rapid method is described for the determination oftrans,trans-muconic acid (2,4–hexadienedioic acid), a biomarker of benzene exposure in urine, by micellar electrokinetic chromatography (MEKC) with thermo-optical absorbance (TOA) detection. Addition of the cationic surfactant cetyltri–methylammonium bromide (CTAB) to a pH 7.0 background electrolyte induces a reversal in the direction of electroosmotic flow (EOF), from cathode to anode. The negatively chargedtrans,trans-muconic acid ion migrates rapidly (< 3 min) toward the anode owing to its electrophoretic mobility supplemented by the surfactant–induced anodic EOF.

ISSN:1082-6076    

DOI:10.1081/JLC-100101776

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor