In this paper we report DNA binding of butadiene monoepoxide, a first metabolite of 1,3-butadiene catalyzed by monooxygenases. We prepared alkylated purines as marker compounds for 32-P-postlabeling and electrochemical analysis and developed methods to measure the corresponding products. The traditional postlabeling assay was modified by incorporating a solid phase extraction column and high-pe...

The potentials and limitations of high-performance liquid chromatography-photodiode array detection are highlighted in respect to its use in the analysis of different biological matrices followed by the identification of unknowns. The logical analytical approach used in clinical and forensic toxicology, vital for the identification of one or more toxic substances as a cause of intoxication, is ...

Different molecular species of phospholipids exhibit distinctly different patterns of biologic behavior. In this minireview, the utility of HPLC for analysis of molecular species of phospholipids is illustrated in studies in which it has been demonstrated that molecular species are selectively synthesized, selectively transported, and selectively participate in enzymatic reactions. HPLC appears...

An improved bioassay for fluconazole was developed. This assay is sensitive in the clinically relevant range (2 to 40 micrograms/ml) and analyzes plasma, serum, and cerebrospinal fluid specimens; bioassay results correlate with results obtained by high-pressure liquid chromatography (HPLC). Bioassay and HPLC analyses of spiked plasma, serum, and cerebrospinal fluid samples (run as unknowns) gav...

This study presents an HPLC method for simultaneous analysis of astaxanthin and its carotenoid precursors from Xanthophyllomyces dendrorhous. The HPLC method is accomplished by employing a C18 column and the mobile phase methanol/water/acetonitrile/ dichloromethane (70:4:13:13, v/v/v/v). Astaxanthin is quantified by detection at 480 nm. The carotenoid precursors are identified by LC-APCI-MS and...

HPLC, column and thin layer chromatography guided studies led to the isolation of seven different compounds in methanolic extracts of Podophyllum hexandrum. The isolated compounds were analyzed using LC-MS and High Performance Liquid Chromatography (HPLC) studies interfaced to mass spectroscopy. Isolated compounds were used successfully as chemical markers for the comparison of the twelve diffe...

Twenty-one samples of commercial annatto formulations have been analyzed for color content (as bixin or norbixin) using a developed HPLC-PDA method and the results compared with those obtained using UV-vis spectrophotometric methods. HPLC-PDA provided superior qualitative and quantitative data, particularly with respect to the determination of colored degradation compounds. Two samples of norbi...

Hazelnuts were investigated for the presence of antioxidant compounds other than tocopherol. Hazelnuts from 2 regions were extracted with methanol:water (2:1 ; v/v). Extracts were subjected to either acid or alkaline hydrolysis but neither improved the separation quality during high pressure liquid chromatography (HPLC) analysis. Nonhydrolyzed extracts of hazelnut had greater antioxidant activi...

During the past decade, technological innovations based on new knowledge of the principles underlying separations processes have transformed column liquid chromatography, the oldest chromatographic technique, into a sophisticated tool for rapidly achieving the most difficult of separations and analyses. Applications of this modern version called High Performance Liquid Chromatography (HPLC) are...

We previously established an analysis method for (measuring) determining the cholesterol levels of 5 major lipoprotein classes (HDL, LDL, IDL, VLDL and chylomicrons) in serum by an anion-exchange high-performance liquid chromatography (AEX-HPLC) method, but lipoprotein(a) [Lp(a)], a well-known risk factor for atherosclerotic diseases, was not determinable. Therefore, we have established new AEX...