Effect of azithromycin-conjugated gold and silver nanoparticles on the cytotoxicity of hepatocellular cancer cells

Azithromycin is a member of macrolide antibiotics, and has been reported to inhibit the proliferation of cancer cells. Nanoparticles particularly nanometals have been recently investigated in cancer chemotherapy owing to their enhanced pharmacokinetic and pharmacodynamic profile over conventional preparations due to nanoscale size and unique physicochemical characteristics. Therefore, this study is intended to explore the role of silver and gold metallic form of an antibiotic Azithromycin (AZM) in exhibiting the anticancer activity against hepatocellular carcinoma cell line (HepG2). After synthesis, Azithromycin conjugated gold and silver nanoparticles were characterized by UV-visible spectroscopy, Fourier transform infrared analysis, Atomic force microscopy and Zeta sizer and zeta potential analysis. HepG2 cells treated with Azithromycin, Gold conjugated Azithromycin (Au-AZM) and Silver conjugated Azithromycin (Ag-AZM) were analyzed for cytotoxic activity via MTT assay and apoptotic potential via nuclear area factor calculation made after processing DAPI stained images. The cytotoxicity data showed that Silver conjugated Azithromycin showed more inhibitory effect (IC50= 33.3µg/ml) on proliferation of HepG2 cells as compared to Gold conjugated Azithromycin (IC50= 78.3µg/ml) and Azithromycin alone (IC50=88.8µg/ml) respectively. Similarly, the Silver conjugated Azithromycin group showed enhanced apoptosis in comparison with Gold conjugated Azithromycin and Azithromycin. In conclusion, this study proposes a potent role of Silver conjugated Azithromycin in attenuation of hepatocellular cancer cell growth, nevertheless further in vivo and clinical trials are required in order to mark its significance as a therapeutic agent.