Carbon Quantum Dots Emulsion for Inhibiting Biofilm Formation in Industrial Filters

Biofilms are biological deposits formed on the biotic and abiotic matrix to resist external stress. Biofilms are formed by bacterial or polysaccharide excretions and resist antibiotics and antimicrobial agents resulting in increased pathogenicity. Besides the medical pathogenicity, biofilms cause fouling in industrial filters, condenser tubes, cooling towers, and other water and wastewater circulation routes. Among several strategies, the application of carbon quantum dots emulsion is one of the promising technologies to counter antibiotic-resistant biofilm-forming bacteria (ARB). In the current study, carbon quantum dots were prepared using sugarcane. In parallel, the bacteria responsible for biofilm formation were isolated and tested for inhibition using the prepared carbon quantum dots. Antibiofilm assay was performed using quantum dots against Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli. Application of quantum dots exhibited a maximum of 73% inhibition of biofilm formation against Pseudomonas aeruginosa, 75% against Staphylococcus aureus, and 85% against Escherichia coli. The results were compared with positive control, gallic acid, which exhibited more than two-fold higher inhibition. Further, carbon quantum dots emulsion produced using Tween 20 was coated on filter cloth which exhibited resistance toward biofilm formation compared to normal filter cloth on prolonged incubations. The results clearly exhibited the efficacy of carbon quantum dots in the inhibition of ARB.