(89f) Active Levy Swimmers and Geometric Design for Anti-Infection Catheters

Antibiotic resistant bacteria pose a serious threat to hospital patients who are already immunocompromised. Recent experiments have demonstrated upstream swimming and super-contamination caused by bacteria inside microfluidic channels, which has been suspected to be responsible for many urinary infection cases. In the first part, our theoretical work on Active Levy Swimmers (ALS) addresses the dynamics of very persistent bacteria within channels. In contrast to the classical model of Active Brownian Particles (ABP), ALS shows fundamentally different non-equilibrium properties that we prove to follow a fractional-order partial differential equation (FPDE). For example, Gaussian diffusion leads to uniform steady state distributions in the bulk, while our FPDE and particle dynamics simulations show a power-law bulk distribution for ALS. Based on the theoretical understanding of the super-contamination mechanism, we propose a novel geometric design for anti-infection catheters inspired by the natural structure of bamboos. Our life-size experiments show that this design successfully disrupts the persistent upstream swimming of bacteria and significantly reduces upstream contamination. Our simulations and microfluidic experiments corroborate the life-size experiments and reveal the underlying mechanism of this design.