Boosting on-demand antibacterial activity using electrical stimulations from polypyrrole-graphene oxide triboelectric nanogenerator

Triboelectric nanogenerator (TENG)-based devices have been considered as a feasible strategy for developing the next generation of self-powered wearable biomedical and healthcare systems. To this end, their antibacterial properties play a key role for gauging their potential for practical applications. Herein, a polypyrrole-graphene oxide (PPy-GO) composite TENG with superior electrical outputs and bactericidal activity is developed by a facile electrodeposition route. The final performance of the TENG can be fine-tuned by controlling electrochemical polymerization conditions as well as the amount of GO nanosheets in the composite layer. Experimental results reveal that the addition of GO to the polymer layer can significantly enhance the triboelectric effect of the electrodes, which was further confirmed by computational modeling. Under optimal conditions, the open-circuit voltage and short-circuit current were obtained as 413.2 V and ⁓ 41 μA, respectively. Marked bactericidal activity was evident for the composite electrode. The antibacterial mechanism was comprehensively investigated through morphological studies, along with qualitative and quantitative measurements for the generation of reactive oxygen species (ROS). The results demonstrate that the synergistic effect of the presence of GO nanosheets and TENG-based electrical stimulations resulted in improvements in ROS generation and S. aureus cellular membrane rupture as the bacterial model.