The binding interactions of the macrolide endectocide ivermectin with the antibiotics ampicillin, chloramphenicol and tetracycline HCL

Abstract

Ivermectin, chloramphenicol, ampicillin and tetracycline HCl are common drugs in human and veterinary practice. The purpose of this study is to investigate the possible binding interactions between ivermectin and the antibiotics chloramphenicol, ampicillin and tetracycline HCl. Isothermal titration calorimetry was used to determine the binding interactions between ivermectin and these antibiotics. Results indicated that, about three molecules of ampicillin can bind to one molecule of ivermectin and about one molecule of chloramphenicol with one molecule of ivermectin. However, no binding stoichiometry can be detected with tetracycline HCl-ivermectin titration. Furthermore, the binding interactions were accompanied by various biophysical and biochemical mechanisms. This is the first report of such interactions of ivermectin with chloramphenicol, ampicillin and tetracycline HCl. There are possible binding interactions of ivermectin with chloramphenicol and ampicillin. Further studies are required for detecting the impact of this binding on biological aspects of drug actions.