UPLC-MS/MS method for determination of retinol and α-tocopherol in serum using a simple sample pretreatment and UniSpray as ionization technique to reduce matrix effects.

Background Our goal was to develop a simple, rapid and precise ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for the determination of retinol and α-tocopherol in serum. Currently published LC-MS/MS methods either require complex extraction procedures (liquid-liquid or solid-phase) or do not meet desirable specifications for imprecision in serum (coefficient of variation [CV] <6.8% and 6.

Hb Melusine and Hb Athens-Georgia: potentially underreported in the Belgian population? Four cases demonstrating the lack of detection using common CE-HPLC methods either for glycated hemoglobin (HbA) analysis or Hb variant screening.

Objective And Importance: Suspected hemoglobin (Hb) variants, detected during HbA measurements should be further investigated, determining the extent of the interference with each method.

Clinical Presentation: This is the first report of Hb Melusine and Hb Athens-Georgia in Caucasian Belgian patients. Intervention & Technique: Since common CE-HPLC methods for HbA analysis or Hb variant screening are apparently unable to detect these Hb variants, their presence might be underestimated.

Gentamicin assay in human serum by solid-phase extraction and capillary electrophoresis.

We describe the development of a capillary electrophoresis method for the determination of gentamicin C1, C1a, C2a, and C2 components in human serum. Using a weak cation-exchanger with 20 mM phosphate buffer, pH 7.4, 200 mM borate buffer, pH 9.

Bioanalysis of tobramycin for therapeutic drug monitoring by solid-phase extraction and capillary zone electrophoresis.

A method based on solid-phase extraction (SPE) and capillary zone electrophoresis (CZE) for the analysis of tobramycin in human serum is presented. An off-line SPE employing a carboxypropyl bonded phase (CBA) cartridge was used for the extraction of tobramycin from human serum. Adsorbed tobramycin was eluted from the CBA cartridge using a mixture of NH(3) (25%, w/v)-methanol (30:70, v/v).