The use of hollow fibre supported liquid membranes and Van’t Hoff plots in the study of diphenylhydramine and chlorpheniramine drugs binding to human 1-acid glycoprotein

T.A.M.Msagati

Abstract

The study of the drug-protein binding using hollow fibre supported liquid membrane (HFSLM) andVanÂ’t Hoff plots is reported. Binding of diphenhydramine hydrochloride (DPH) and (±) – chlorpheniramine maleate salt (CPA) to human 1-glycoprotein (AGP) was investigated at optimal conditions of the HFSLM. The binding was found to be effective within the first 400 minutes for DPH and about 2000 minutes for CPA after incubation at the concentration ranges studied. The effect of pH in the binding of the drugs to AGP was studied and showed that the optimal pH was 8 and 9 for DPH and CPA respectively. The kinetic patterns of the interactions at various temperatures as well as at physiological conditions of temperature and pH were carried out and by using VanÂ’t HoffsÂ’ plot it was found that the association constant forDPHwas 0.96 x 103mol L-1 and that ofCPAwas 1.02 x 103molL-1.