Bacterial growth inhibition in spring water utilizing silver nanoparticles: Optimization using central composite design

Abstract

Ensuring safe drinking water remains a significant challenge due to the prevalence of waterborne diseases. While chlorine-based and UV-based methods effectively kill pathogens, they often generate harmful byproducts. Consequently, there's a pressing need for innovative techniques, such as utilizing silver nanoparticles(AgNPs) renowned for their antibacterial properties. In this study, a chemical reduction technique was employed to synthesize AgNPs. Subsequently, these AgNPs underwent comprehensive characterization using techniques such as FTIR, XRD,TGA and XPS. The synthesized nanoparticles were then applied for disinfecting spring water. The experimental design was meticulously planned using the central composite design method (CCD) from Response Surface Methodology (RSM), facilitated by Design Expert software. Three key factors: AgNPs, pH, and contact time were varied across three levels, resulting in a total of 20 designed experiments. These experiments were conducted in accordance with the specified run order, culminating in the achievement of maximum bacteria growth inhibition efficiency of 99.72 % at the optimal conditions of 0.01 mg/100 mL AgNPs dose, a pH of 6, and a contact time of 20 min. Overall, the findings of this study underscore the efficiency of AgNPs in disinfecting spring water.

Keywords

• Bacteria
• Central composite design
• Disinfection
• Optimization
• Silver nanoparticles