HPLC determination of morphine, morphine-3-glucuronide and morphine-6-glucuronide in human serum of oncological patients after administration of morphine drugs.

A simultaneous determination of morphine (M) and its two metabolites, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G), by HPLC in the serum of oncological patients is described. The compounds are extracted from the serum by means of Chromabond C18--EC solid-phase-extraction cartridges, separated on a Symmetry C18 analytical column (150 x 4.9 mm, 5 microm) and detected by a UV detector at 210 nm.

Matrix solid-phase dispersion for the liquid chromatographic determination of phenolic acids in Melissa officinalis.

Matrix solid-phase dispersion (MSPD) was used for sample preparation of plant material (Melissa officinalis, Lemon Balm) prior to liquid chromatography of rosmarinic, caffeic and protocatechuic acids, phenolic compounds present in this herb. Different MSPD sorbents and various elution agents were tested and the optimal extraction conditions determined with the aim to obtain extraction recoveries greater than 90% for all analytes.

Chiral separation of verapamil and some of its metabolites by HPLC and CE.

HPLC and CE assays were developed for chiral separations of verapamil and its metabolites in serum samples. Three chiral HPLC columns (Chiralcel OJ, Chiralpak AD and Chiralcel OD-R) were tested in normal and reverse-phase modes. All HPLC analyses were performed with fluorescence detection at 276 and 310 nm.

Column-switching chromatographic determination of itraconazole and its metabolite hydroxy-itraconazole in human serum.

A column-switching HPLC assay is described for the determination of the antifungal agent itraconazole and its main metabolite hydroxy-itraconazole in serum samples. Three precolumns packed with alkyl-diol silica sorbents differing in alkyl chain length are compared in the sample clean-up step. Chromatographic separation is achieved with a Symmetry C8 column.

Direct analysis of food samples by high-performance liquid chromatography.

A short review on the sample analysis of food samples by high-performance liquid chromatography is presented. The paper is focused on direct injection of liquid samples, automated solid-phase extraction and column switching techniques, on-line dialysis and application of restricted-access media.