Wireless Nanobioelectronics for Electrical Intracellular Sensing

For the field of bioelectronics to make an impact on healthcare, there is an urgent requirement for the development of “wireless” electronic systems to enable modulation of chemistry inside of cells. Herein we report on an intracellular wireless electronic communication system. This is based on modulating the electrochemistry on gold nanoparticles without the nanoparticles having any physical electrical connection to a power supply at relatively low externally applied potentials. The system is made functional by modifying water-soluble gold nanoparticles (ws-AuNPs) with a Zn(II) meso-tetrakis(4-carboxyphenyl)porphyrin sodium salt (Na-ZnTCPP). Na-ZnTCPP modified ws-AuNPs are taken up by cells and are shown to be noncytotoxic. It is demonstrated that the redox state of the Zn-porphyrin modified gold nanoparticles is controlled, and a fluorescent output can be used to measure this during the application of an external electrical potential. When the porphyrin modified nanoparticles were located intracellularly and external potentials were applied, the same effect was observed. This provides an attractive “wireless” approach to develop bioelectronic devices for modulating and sensing cellular behavior.