Because of their antibacterial activity, silver nanoparticles (AgNPs) have been explored in biomedical applications. Similarly, nitric oxide (NO) is an important endogenous free radical with an antimicrobial effect and toxicity toward cancer cells that plays pivotal roles in several processes. In this work, biogenic AgNPs were prepared using green tea extract and the principles of green chemistry, and the NO donor S-nitrosoglutathione (GSNO) was prepared by the nitrosation of glutathione. To enhance the potentialities of GSNO and AgNPs in biomedical applications, the NO donor and metallic nanoparticles were individually or simultaneously incorporated into polymeric solid films of poly(vinyl alcohol) (PVA) and poly(ethylene glycol) (PEG). The resulting solid nanocomposites were characterized by several techniques, and the diffusion profiles of GSNO and AgNPs were investigated. The results demonstrated the formation of homogeneous PVA/PEG solid films containing GSNO and nanoscale AgNPs that are distributed in the polymeric matrix. PVA/PEG films containing AgNPs demonstrated a potent antibacterial effect against Gram-positive and Gram-negative bacterial strains. GSNO-containing PVA/PEG films demonstrated toxicity toward human cervical carcinoma and human prostate cancer cell lines. Interestingly, the incorporation of AgNPs in PVA/PEG/GSNO films had a superior effect on the decrease of cell viability of both cancer cell lines, compared with cells treated with films containing GSNO or AgNPs individually. To our best knowledge, this is the first report to describe the preparation of PVA/PEG solid films containing GSNO and/or biogenically synthesized AgNPs. These polymeric films might find important biomedical applications as a solid material with antimicrobial and antitumorigenic properties.
Keywords: S-nitrosoglutathione; antibacterial; cytotoxicity; nitric oxide; polymeric films; silver nanoparticles.