Use of non-covalent labeling in illustrating ligand binding to human serum albumin via affinity capillary electrophoresis with near-infrared laser induced fluorescence detection.

This paper demonstrates the use of a near-infrared (NIR) dye as a non-covalent label for human serum albumin (HSA). The dye is a water soluble, heptamethine cyanine dye. The utility of the dye as a tracer illustrating the binding of various drugs to HSA is demonstrated via affinity capillary electrophoresis with near-infrared laser-induced fluorescence detection (ACE-NIR-LIF). Additionally, the factors affecting the separation of relevant species were investigated. The change in quantum yield of the dye upon complexation with HSA was calculated. Spectrophotometric measurements were conducted to study the stoichiometry of the dye albumin complex.

Studies of polymerized sodium N-undecylenyl-L-valinate in chiral micellar electrokinetic capillary chromatography of neutral, acidic, and basic compounds.

The polymerized surfactant poly(sodium N-undecylenyl amino L-valinate) [poly(L-SUV)] has been used in micellar electrokinetic capillary chromatography for the chiral separation of various acidic and basic drugs, as well as neutral compounds. Under the conditions studied, poly(L-SUV) was shown to be a very versatile anionic chiral selector in the pH range of 5.6-11. The micelle was used for the enantioseparation of coumarinic anticoagulant drugs with various buffers under moderately acidic conditions. Neutral and alkaline buffer conditions were used to successfully separate the neutral atropisomers (+/-)-1,1'-bi-2-naphthol, (+/-)-1,1'-binaphthyl-2,2'-diamine, and Tröger's base. Chiral separation of the cationic paveroline drugs, laudanosine, norlaudanosoline, and laudanosoline, was influenced by pH and the use of coated capillaries. The acquired data focused on optimizing the migration times, capacity and separation factors, and electrophoretic mobilities of the various racemic mixtures.