Recent American Food and Drug Administration guidelines have effectively determined that mixtures of chiral compounds can no longer be brought to the pharmaceuticals marketplace. These guidelines require a means for chiral detection and compound separation. This article describes separation and detection of chiral pharmaceuticals using HPLC with circular dichroism detection. Two over-the-counte...

BACKGROUND The isolation of highly pure copper-free methanobactin is a prerequisite for the investigation of the biogeochemical functions of this chalkophore molecule produced by methane oxidizing bacteria. Here, we report a purification method for methanobactin from Methylosinus trichosporium OB3b cultures based on reversed-phase HPLC fractionation used in combination with a previously reporte...

Background Non-enzymatic hydroxylation of aromatic compounds to the respective phenolic derivatives is a possible metabolic pathway of xenobiotics. The formed metabolites can undergo consecutive oxidative reactions with free radicals to form potential toxic molecules. Objective Development of HPLC methods to separate, identify and quantitate the main products formed from salicylic acid, 2,3-d...

dispersive liquid-liquid microextraction method (dllme) combined with high-performance liquid chromatography-ultraviolet detection (hplc-uv) was used to determine thiamine (b1), nicotinamide (b3) and pyridoxine (b6) in sour cherry juice. this method was rapid, simple and sensitive. separation was accomplished using a c18 column. the optimum chromatographic conditions were found to be: mobile ph...

oDays High-performance liquid chromatography (HPLC) for analysis of phospholipids has traditionally employed ultraviolet detection of the eluted compounds. The evaporative laser light-scattering detector (ELSD) offers new opportunities for quantitative analysis of lipids. Phospholipids were isolated from crude and degummed oils prepared from soyheans subjected to storage at high moisture conten...

of this work is to assess the impact of such MU detecPacketized random access based on Code Division Multiple Access (CDMA) is considered. Our primary aim is to assess the impact of (uncoded) multi-user (MU) detectors on the performance of CDMA with slotted ALOHA. The impact of respective multiple packet reception capability for the matched filter and MMSE detector on delay/throughput improveme...

Purpose: To develop and validate a sensitive and specific HPLC assay for cladribine (CdA) in plasma for pharmacokinetic studies in rats. Methods: CdA and the internal standard AZT were purchased from Sigma-Aldrich Chem. The HPLC system consisted of a Shimadzu LC-9A pump, a 3 μm, 250 x 2.0 mm I.D. high speed C18 column (Jupiter), preceded by a 5 μm 4 x 4 mm I.D. C18 guard column (Licrocart), an ...

We have developed a simplified and improved high performance liquid chromatography (HPLC) method for the detection and quantitation of tissue lipid using a new laser light-scattering detector (Varex model ELSD II). This detector has a limit of sensitivity of 50 ng for neutral lipid and 200 ng for most phospholipids with excellent reproducibility. By coupling the ELSD II with a ternary gradient ...

Purpose: To develop, validate and compare two chromatographic methods - high performance liquid chromatography with diode array detector ((HPLC-DAD) ultraviolet detection (UPLC-UV) for the effective analysis of polyphenols in Moringa oleifera leaves.Methods: HPLC-DAD UPLC-UV were applied accurate determination eleven major leaves. The conditions was determined on C18 column by gradient elution ...