Protein Redox by Piezoelectric Acousto-Nanodevice

Redox reactions in proteins, mediated by the electron transfer, are the engine that drives crucial life-sustaining functions including respiration, photosynthesis, metabolism, and cell apoptosis. Thus, the ability to modulate the redox proteins through an external stimulus presents a unique opportunity in attuning the system. Piezoelectric nanoparticles offer underexplored advantage of the electrical interaction under external acoustic waves; ultrasound offers biosafety and long penetration depth. In this work, we present the acousto-nanodevice capable of modulating the redox state of a redox protein (i.e., reduced cyt c) under ultrasonic irradiation. To enable the unidirectional electron transfer under alternating fields, we designed the device to have asymmetric surfaces. Our results clearly demonstrated that protein oxidation occurs only when asymmetrically functionalized acousto-nanodevice was activated by ultrasound. We also experimentally confirmed that the acousto-nanodevice may engineered to be either an oxidation or reduction agent, depends on the types of the surface metal. Based on the various control experiments, we postulate the working mechanism of the acousto-nanodevice is that the alternating electrical polarization of BTO nanoparticles can tentatively modulate the workfunction of the metal, thereby inducing unidirectional electron transfer from the protein redox centers to the acousto-nanodevice.