title: Hybrid upconversion nanomaterials for optogenetic neuronal control.
abstract: Nanotechnology-based approaches offer the chemical control required to develop precision tools suitable for applications in neuroscience. We report a novel approach employing hybrid upconversion nanomaterials, combined with the photoresponsive ion channel channelrhodopsin-2 (ChR2), to achieve near-infrared light (NIR)-mediated optogenetic control of neuronal activity. Current optogenetic methodologies rely on using visible light (e.g. 470 nm blue light), which tends to exhibit high scattering and low tissue penetration, to activate ChR2. In contrast, our approach enables the use of 980 nm NIR light, which addresses the short-comings of visible light as an excitation source. This was facilitated by embedding upconversion nanomaterials, which can convert NIR light to blue luminescence, into polymeric scaffolds. These hybrid nanomaterial scaffolds allowed for NIR-mediated neuronal stimulation, with comparable efficiency as that of 470 nm blue light. Our platform was optimized for NIR-mediated optogenetic control by balancing multiple physicochemical properties of the nanomaterial (e.g. size, morphology, structure, emission spectra, concentration), thus providing an early demonstration of rationally-designing nanomaterial-based strategies for advanced neural applications.
authors.affiliation: Department of Chemistry & Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA. kblee@rutgers.edu.
authors.forename: Shreyas
authors.initials: S
authors.lastname: Shah
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Liu
authors.forename: Nicholas
authors.initials: N
authors.lastname: Pasquale
authors.forename: Jinping
authors.initials: J
authors.lastname: Lai
authors.forename: Heather
authors.initials: H
authors.lastname: McGowan
authors.forename: Zhiping P
authors.initials: ZP
authors.lastname: Pang
authors.forename: Ki-Bum
authors.initials: KB
authors.lastname: Lee
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D000075402:Channelrhodopsins; D008027:Light; D051379:Mice; D049329:Nanostructures; D036103:Nanotechnology / Q000379:methods; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D062308:Optogenetics / Q000379:methods*
chemical_list: D000075402:Channelrhodopsins