Remote Non-Genetic Optical Modulation Using Nanomaterials

The Magic of Combining Light and Nanomaterials: Precise Control of Biology

In the last several decades, input/output (I/O) interfaces with electroactive cells and tissues have steadily improved through a variety of techniques and materials, enabling increased spatial and temporal control. We are working on optical modulation of cells and tissue activity using nanomaterials to resolve the limitations of the current state-of-the-art platforms. The optical modulation provides control with high spatiotemporal resolution, low cytotoxicity, and without any genetic manipulation. We are designing and building up the material library with high light absorption, efficient optical energy conversion for direct modulating electrophysiology and activity of cells.

NT-3DFG: Broad-band absorber with high absorption for neural modulation

We have used our novel hybrid-nanomaterial- Nanowire Templated 3D Fuzzy Graphene (NT-3DFG) for remote, non-genetic optical modulation of neuronal activity both in two- and three-dimensions (2D and 3D). The unique structure of this hybrid-nanomaterial leads to extraordinary optical and photothermal properties that enable stimulation of neurons with laser energies as low as sub-hundred nanojoules! The <1.5 µm diameter of NT-3DFG allows stimulation with high precision and sub-cellular spatial resolution. This platform will address challenges in tissue engineering by enabling non-invasive, precise tissue stimulation.

Ti3C2Tx (MXene): 2nm thick 2D nanomaterial (!) for neural modulation

Two-dimensional (2D) Ti3C2Tx and other MXenes have attracted significant attention in photothermal therapy (PTT) due to their high NIR absorbance, high photothermal conversion efficiency, and non-cytotoxicity. Recently, we demonstrated that Ti3C2Tx is an outstanding candidate for optical modulation of neural activity. Ti3C2Tx photothermal response measured at the single-flake level resulted in local temperature rises of 2.31 ± 0.03 K and 3.30 ± 0.02 K for 635 nm and 808 nm laser pulses (1 ms, 10 mW), respectively. Dorsal root ganglia (DRG) neurons were photothermally stimulated using Ti3C2Tx films and flakes with as low as tens of micro-joule per pulse incident energy (635 nm, 2 μJ for film, 18 μJ for flake) with sub-cellular targeting resolution. Ti3C2Tx has straightforward and large-scale synthesis protocol, which will allow translation in multiple scales from single cell to engineered tissues.

Calcium Influx achieved by DRG-Ti3C2Tx Film Interfaces