Quantum Dot Enhanced Bioluminescent Emitter for Optogenetic Stimulation.

Abstract

Optogenetics enables precise control of neuronal activity using light-sensitive proteins. However, dependence on external light sources introduces key limitations. Bioluminescence-driven approaches offer a promising alternative by generating light internally through proteins such as Aequorin, which emits blue light in response to calcium dynamics. While this emission is compatible with blue light sensitive opsins, its practical effectiveness is limited by the relatively high activation thresholds and functional flexibility of these opsins. Red-sensitive opsins offer a broader range of functionality, including both excitatory and inhibitory control, and certain variants, such as ChRmine, exhibit exceptionally high light sensitivity. These properties make them particularly well suited for low-power bioluminescent systems. We propose a Biological Optical Emitter (BOE) consisting of an Aequorin containing a core surrounded by a polydimethylsiloxane (PDMS) shell embedded with CdSe/ZnS quantum dots to enable wavelength conversion from blue to red. In this design, the native blue emission is not treated as the functional stimulation source; instead, it serves as an internal excitation mechanism for quantum dots, driving red-shifted emission that constitutes the effective output of the system. Our modeling results demonstrate that, despite conversion losses, the system operates effectively as a red-light bioluminescent stimulator, enabling optogenetic activation under power-limited conditions at long distances.