Inducing repetitive action potential firing in neurons via synthesized photoresponsive nanoscale cellular prostheses

Recently we reported an analysis that examined the potential of synthesized photovoltaic functional abiotic nanosystems (PVFANs) to modulate membrane potential and activate action potential firing in neurons. Here we extend the analysis to delineate the requirements on the electronic energy levels and the attendant photophysical properties of the PVFANs to induce repetitive action potential under continuous light, a capability essential for the proposed potential application of PVFANs as retinal cellular prostheses to compensate for loss of photoreceptors. We find that repetitive action potential firing demands two basic characteristics in the electronic response of the PVFANs: an exponential dependence of the PVFAN excited state decay rate on the membrane potential and a three-state system such that, following photon absorption, the electron decay from the excited state to the ground state is via intermediate state(s) whose lifetime is comparable to the refractory time following an action potential.From the Clinical EditorIn this study, the potential of synthetic photovoltaic functional abiotic nanosystems (PVFANs) is examined under continuous light to modulate membrane potential and activate action potential firing in neurons with the proposed potential application of PVFANs as retinal cellular prostheses.

Graphical AbstractWe analyze the photophysical requirement for synthesized photovoltaic functional abiotic nanosystems (PVFANs, left panel) to modulate membrane potential and induce repetitive action potential firing in neurons under continuous-wave light, a capability desirable for the proposed potential application of PVFANs as retinal cellular prostheses to compensate for loss of photoreceptors. The analyses show that repetitive action potential firing (upper right panel) demands a three-state PVFAN system (lower right panel) such that, following photon absorption, the electron decay from the excited state to the ground state is via a set of intermediate state(s) of lifetime comparable to the refractory time following an action potential.Figure optionsDownload high-quality image (157 K)Download as PowerPoint slide