title: Elimination of peak deformation in the liquid chromatographic separation of a strongly protein-bound drug from directly injected blood plasma samples.
abstract: Direct injection of blood plasma samples into reversed-phase columns resulted in skewed chromatographic peaks for the drug naproxen. The skew is shown to be due to strong binding of naproxen to albumin present in the blood plasma. Methods to eliminate the peak skew have been investigated. They include changes of the composition of the eluent and of the sample solution in order to decrease the degree of binding of the drug to albumin. The methods studied were dilution, addition of displacers, change of pH and change of methanol concentration. Calculations based on known binding constants indicate that the degree of peak skew was directly influenced by the degree of protein binding of the drug in the sample solution.
mesh_terms: D002851:Chromatography, High Pressure Liquid; D006863:Hydrogen-Ion Concentration; D008433:Mathematics; D000432:Methanol; D008956:Models, Chemical; D009288:Naproxen / Q000097:blood*; D011485:Protein Binding; D012709:Serum Albumin / Q000378:metabolism*
chemical_list: D012709:Serum Albumin; D009288:Naproxen; D000432:Methanol