Controlled Intracellular Cargo Delivery Using a Polypyrrole-Silicon Nanowire Hybrid Platform

Intracellular cargo delivery is a critical and challenging step in establishing direct bio-inorganic communication. Silicon nanowire arrays, utilizing high aspect ratio dimensions, have emerged as a powerful platform for electrically connecting the intracellular space to external devices. We have developed and characterized a conductive polypyrrole-nanowire device capable of storing molecular cargo for electrically triggered intracellular delivery. Fluorescent cargos, doped in electroresponsive polypyrrole matrices at wire tips as well as entire NW arrays, were released into endothelial cells upon polypyrrole reduction. The combined polymer carrier and nanowire architecture demonstrated comparable delivery kinetics to transfer from solution while requiring an order of magnitude less cargo loading. This hybrid polymer-semiconductor platform extends methods available for intracellular delivery and links electrical signaling from artificial systems with living molecular transduction.