Label-free detection of ATP release from living astrocytes with high temporal resolution using carbon nanotube network

Abstract

Owing to its unique combination of electrical, physiochemical, and one-dimension structural properties,

single-walled carbon nanotube (SWNT) has recently emerged as a novel nanoelectronic biosensor for

biomolecular detection with extraordinary sensitivity and simple detection scheme. All the realizations

so far, however, are limited to static in vitro measurement. Dynamic detection of biomolecule release from

living cells which may occur in millisecond timescale has yet to be demonstrated. In the present work,

SWNT network was utilized to directly interface with living neuroglial astrocytes and label-freely detect

the triggered release of adenosine triphosphate (ATP) from these cells with high temporal resolution. The

secreted ATP molecules diffuse into the narrow interface gap between the SWNT-net and the astrocyte,

and interact with the nanotubes. Highly charged ATP molecules electrostatically modulate the SWNT

conductance leading to measurable current response. This technique provides a novel platform to study

ATP release and signaling which play important roles in astrocyte–neuron crosstalk and other essential

cellular functions.