Session: Applications & Implications of Nanomaterials in the Environment:

Growth of undesired bacteria can cause numerous problems. Seeking for effective and sustainable bacteria inactivation technique is an everlasting effort. Applying nano-enhanced electric-field treatment (EFT) for bacteria inactivation is an emerging technique. Superior performance has been demonstrated with bench-scale devices, and irreversible electroporation is considered to be the main inactivation mechanism. Nevertheless, such a bacteria inactivation process has not been studied at a single-cell level, and the mechanism explanation lacks direct evidence. In this study, we have developed a lab-on-a-chip platform to conduct the nano-enhanced EFT under a microscope to observe the bacteria inactivation process in situ and in real time. The phenomenon that bacteria are locally inactivated at the tips of nanowedges is visualized for the first time. The bacteria inactivation is a rapid process with the cell damage occurs within 0.2 seconds.The observations with different applied voltages, electrode designs, and distribution of the inactivated cells are all consistent with the mechanism of bacteria inactivation by electroporation. The bacteria inactivation process for different bacteria strains is also visualized. Results gained from this study provide fundamental supports for the further development and broader applications of nano-enhanced EFT for bacteria inactivation.

Ms Ting Wang

PhD student, Georgia Institute of Technology

Appearances