Silver-Chitosan Nanocomposite Prepared with Aqueous Sodium-Hydroxide and Aqueous Acetic Acid Solutions: Characteristics and Their Cytotoxic Effects

In this study, cytotoxic effects of silver-chitosan nanocomposites with aqueous sodium hydroxide solution (SCNC-ASHS) and aqueous acetic acid solution (SCNC-AAAS) were evaluated in vitro. The morphology of the synthesized nanoparticles was characterized by Fourier-Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Their cytotoxicities were then evaluated using MTT in concentrations of 1.56 to 400 µg/ml, and Acridine orange/Ethidium bromide (AO/EB) staining test after 24 h and 48 h. Results showed that the highest cytotoxicity was at 400 µg/ml concentration at which SCNC-ASHS respectively showed 80.57% and 84.37% toxicity on Vero and HT-29 cells after 24 h, and 82.20% and 84.84% after 48 h. While, the cytotoxicities for SCNC-AAAS on Vero and HT-29 cell lines were respectively 80.63% and 87.64% after 24 h, and 83.60% and 87.44% after 48 h. The most toxicity on HT-29 cells belonged to SCNC-AAAS with IC50 of 40.4 µg/ml. In the staining test, SCNC-AAAS revealed 41.84% HT-29 cell viability at 25 µg/ml concentration and 37.51% Vero cell viability at 6.25 µg/ml concentration. Generally, by increasing both SCNCs concentrations, the cell viabilities were decreased, and early and late apoptosis and necrosis were increased in AO/AE test. In conclusion, types of nanoparticles, synthesis methods, and different cell lines play considerable roles in inducing cytotoxicity. According to the higher significant cytotoxicity effects of both SCNCs on colon cancerous cells (HT-29) than normal cells (Vero) (p<0.05), it seems that they have anticancer effects; of those SCNC-AAAS displayed the higher effect with the IC50 of 4.4 µg/ml on HT-29 cells.