A Comparative Evaluation of Antibacterial activity of Silver and Gold Nanoparticles Synthesized using a Poly(amic) acid

Abstract

Water is the most abundant natural resource covering about 70 percent of the earth’s total surface. The supply of clean and safe water for domestic use, however, remains the most important scientific and technological challenge facing the globe today. Pollution as a result of human organic waste, generates a large volume of waste water containing deadly microbes including Escherichia coli (E. coli) and Streptococcus aureus (S. Aureus) has been cited as the major cause of water pollution and contamination. To realize the Sustainable Development Goal (SDG) number 6, sustainable and environmentally friendly approaches for waste water treatment and remediation is therefore critical. Recently, Nanotechnology has been widely investigated as efficient and effective pathway for waste water treatment and remediation. Both silver (Ag) and gold (Au) nanoparticles (NPs) have shown activity against Escherichia coli and staphylococcus aureus, but the degree of activity is not yet clear. This study intended to compare the antibacterial activities of synthesized AgNPs, AuNPs and Ag/AuNPs blends against E. coli and S. aureus. Synthesized AgNPs, AuNPs and Ag/AuNPs blends were characterized by UV-Visible spectroscopy, cyclic voltammetry and SEM analysis. SEM showed that AgNPs, AuNPs and Ag/AuNP blend were aggregated, spherically shaped and dispersed throughout the matrix of the polymer. Ag/AuNP blends synthesized under ambient temperature showed an excellent antimicrobial efficacy against E. coli and S. aureus compared to AgNPs, AuNPs and Ag/AuNPs synthesized under ambient temperature or 70oC. However, we recommend further investigations to understand the potential risks of the application.