Microfluidics-based engineered silver nanoparticles to control growth and biofilm formation in bacterial pathogens causing dental infection

Dental infections caused by Streptococcus mutans and Enterococcus faecalis are major contributors to dental caries and root canal infections due to their strong biofilm forming ability across all age groups. This present study aimed to develop a microfluidics-assisted green synthesis approach for the fabrication of Clitoria ternatea-derived silver nanoparticles (CtAgNPs) and to evaluate their antibacterial and antibiofilm potential in dental pathogens. The bioactive compounds present in Clitoria ternatea floral extract act as a natural reducing and stabilizing agent within a microfluidics system. The synthesized CtAgNPs were characterized to confirm their physicochemical properties. UV-Visible spectroscopy reveals the surface plasmon resonance peak at 423 nm, FESEM imaging showed the spherical morphology with an average particle size of 151.6 nm, and a zeta potential of - 26.1 mV, indicating good colloidal stability. FT-IR analysis confirmed the presence of phytochemical-derived functional groups on the surface of CtAgNPs. Toxicity assessment using zebrafish (Danio rerio) embryos confirmed the biocompatibility and non-toxic nature of CtAgNPs. CtAgNPs demonstrated strong antibacterial activity with MIC values ranging from 3.125 to 6.25 µg/mL and exhibited more than 75% inhibition of biofilm formation in both S. mutans and E. faecalis. Mechanistic investigations revealed that the nanoparticles induced oxidative stress, characterized by increased lipid peroxidation (MDA), reduced antioxidant enzyme activities (CAT and SOD), and leakage of intracellular proteins and sugars, indicating membrane damage. Overall findings demonstrate that microfluidics-assisted green-synthesized CtAgNPs effectively inhibit the growth and biofilm formation of dental pathogens, highlighting their potential as an eco-friendly nanotherapeutic strategy for the prevention and management of dental biofilm-associated infections.