Bacterial inactivation via laser-driven gold nanoparticle heating: simulation and analysis

This study utilizes CFD technique to simulate the inactivation of E. coli bacteria within a microfluidic chamber, employing gold nanoparticles irradiated by a laser beam. Employing a single-phase model, the presence of bacteria is considered by treating thermal properties in the governing equations as effective, combining those of water and bacteria using established correlations from scientific literature. The conversion of light into heat is modeled with parameters derived from scientific literature, featuring a defined source term quantifying the converted light into heat. Introducing a User Defined Scalar (UDS) employing a first-order kinetic model described by the Arrhenius equation for the decay coefficient captures the bacteria’s response to irradiation. A dedicated User Defined Function (UDF) is developed to implement this model, allowing the simulation to account for the reduction in bacterial concentration over time. The results uncover intricate dynamics in bacterial response to laser-induced thermal effects, showcasing the potential for effective bacterial control. Furthermore, the model is rigorously validated against experimental data, affirming its accuracy and robustness in reproducing real-world thermal effects.