Binding affinity of amlodipine, atorvastatin and telmisartan drugs to purified bacterial melanin pigment: A kinetic study

Abstract

Amlodipine, atorvastatin and telmisartan are the most commonly used pharmaceutical drugs against cardiovascular disease, management of hypertension and in the treatment of angina. They have side-effects like edema, allergic reactions, breathing problems, etc. The melanin pigment from Klebsiella sp. GSK has the ability to adsorb pharmaceutical drugs, metals ions and to scavenge free radicals. We have studied here the binding of these drugs to melanin pigment at different concentrations and temperatures. It shows that these drugs in higher concentrations form stable complexes with melanin pigment. The amount of drug bound to melanin increases with increase in initial drug concentration. The drug-binding properties of melanin pigment were investigated kinetically. Telmisartan and amlodipine bind strongly at 40 °C (59 and 25.8 ?g/mg, respectively) than atorvastatin (18 ?g/mg). Batch adsorption, uptake kinetics, Langmuir and Freundlich equations and temperature adsorption studies were also conducted with melanin pigment. © 2013 The Korean Society of Pharmaceutical Sciences and Technology.