A nano-needle interface self-assembled by using cell migration for recording intracellular activity: Nano-needle durability

This paper proposes a nano-needle intracellular interface which was assembled by using a cell's own locomotion force. This interface was designed for large scale intracellular recording for development of an artificial synaptic device. We previously demonstrated a method to insert a nanostructure into a living cell using cell locomotion. To achieve an intracellular nanoelectrode, we employed such cell migration on an extracellular matrix as the driving force to insert a nanoelectrode into a plasma membrane. In this study, we describe intracellular nanoelectrodes inserted by the cell migration force which are used to construct intracellular recording devices. Each microwell had a low cell binding glass plate which had cellular adhesive molecules, and there was an electrically conductive tungsten nanoneedle about 190 nm in diameter on the bottom of the microwell. Cells can adhere only in the microwell; thus they are pulled down by their own body and are inserted into the nanoneedle by their own migration force. Then, the living cellular activity can be measured from the electrically conductive nanoneedle. Using this concept, we attempted to achieve a long-lasting intracellular multi channel interface between living cells and artificial implements without making a precise mechanical alignment and without an invasive procedure. This report explains the fabrication and electrical characteristics of the interface for development of the physical part of the cell-machine interface.