A simple and sensitive assay for ampicillin in pharmaceuticals using gold nanoparticles as spectroscopic probe reagent

A novel kinetic spectrophotometric method is developed for determination of ampicillin. The method is based on aggregation of gold nanoparticles in a chemical process that involved decomposition of ampicillin catalyzed by cadmium ion in methanol as solvent. The optimum experimental conditions for determination of ampicillin were established. The method permitted determination of ampicillin in a concentration range of 16.0-96.0 A mu g ml(-1) with a detection limit of 13.0 A mu g ml(-1). The interferences of the species which are mostly available in biological samples were not significant in determination of ampicillin. The method is simple and sensitive for analyzing of ampicillin and is applicable for its assay in pharmaceutical formulations.