PI: Xuanhong Cheng

Co-PI(s): N/A

University: Lehigh University

Industry partner: Dow

Various investigations have confirmed the impact of plastic polymers on the composition and function of microbial communities in aqueous environments. Additionally, recent studies have revealed some capability of bacteria to degrade certain plastic polymers. The mutual influences between bacteria and plastic polymers demand new tools to characterize their binding in solutions in a biocompatible and real-time fashion. The proposed research will address this demand by applying the microscale thermophoresis (MST) approach to bacteria-polymer mixtures. To monitor molecular migration in a temperature field, the MST approach has been widely adopted for probing biomolecular binding affinity in the past decade, while its usage in particle suspensions is scarce. We will first test the feasibility of using synthetic particles and polymers. This will reveal appropriate particle concentrations and detection sensitivity, which will guide subsequent measurements of bacterial systems. We will then study the binding of selected bacterial strains and polymer types commonly found in natural water environments. The binding will be compared against toxicity or adaptation of bacteria. Similar studies will be carried out using bacteria and selected polymer degradation products. Furthermore, the binding of polymers to a mixture of bacteria containing two to three strains will reveal the synergistic/competitive effect among the strains. This research may help answer the questions of selective toxicity and adaptation of bacteria to plastics in water. Furthermore, it may contribute to engineering environmental microbiomes to mitigate plastic pollution in water.