A New Class of Gold Nanoantibiotics- Direct Coating of Ampicillin on Gold Nanoparticles

Need for novel, innovative strategies for developing antibiotics is becoming a necessity due to an increasing number of rapidly evolving micro-organismal threats. Antibiotic encapsulated gold nanoparticles (GNPs) are one such strategy showing promise. We report the development of ampicillin encapsulated gold nanoparticles (Amp-GNPs) that possess highly effective, dose dependant antibacterial activity. In this method, ampicillin molecules have been coated on individual GNPs which can then serve as drug carrier devices. Our method for synthesizing Amp-GNPs is an entirely ecofriendly, single step reaction taking place in an aqueous buffer. Following characterization of Amp-GNPs, we find them to be ˜15 nm in diameter and spherical in shape. We have tested the antibacterial activity of Amp-GNPs against multiple strains of bacteria, both Gram-positive and Gram-negative, and have found Amp-GNPs to be highly efficient against all tested strains. By examining the mechanism of Amp-GNPs antibacterial activity, it was determined that Amp-GNPs disrupt the bacterial cells membrane when coming into contact with the cells, thus disturbing the cell equilibrium, leading to cell lysis or necrosis. Amp-GNPs have been shown to exhibit significant potential and ability to enter the medical field’s arsenal to fight infectious disease.