Noninvasive near-infrared light triggers the remote activation of thermo-responsive TRPV1 channels in neurons based on biodegradable/photothermal polymer micelles.

In this study, we developed a novel biodegradable/photothermal polymer micelle-based remote-activation method for a temperature-sensitive ion channel, namely transient receptor potential cation channel subfamily V member 1 (TRPV1). Biodegradable/photothermal polymer micelles containing indocyanine green (ICG-micelles) were prepared using a simple one-pod mixing method. The obtained ICG-micelles showed biocompatibility and biodegradability. Furthermore, under tissue-penetrable near-infrared (NIR) laser irradiation, the ICG-micelles exhibited excellent photothermal effects and NIR emission. Moreover, NIR light-induced remote activation of neurons was successfully performed. ICG-micelles loaded with anti-TRPV1 antibodies effectively bound TRPV1 on cell membranes, and accelerated Ca ion influx into neuronal cells was induced under NIR irradiation. Based on these findings, it is anticipated that the ICG-micelles can serve as a novel noninvasive remote-activation tool for neuronal cells.