Hybrid protein-quantum dot nanoscale structures for biosensing and photovoltaics

Utilizing the direct energy transfer mechanism existing between semiconductor quantum dots (QD) and the hydrogen ion protein pump bacteriorhodopsin (bR), a multi-functional bioelectronics platform is demonstrated. Fluorescence resonance energy transfer (FRET) coupled QD-bR systems have been proven in both aqueous and dried film states, allowing for the vast QD optical absorbance range to directly contribute energy to the bR proton pumping sequence. A nanoscale deposition technique was employed to construct hybrid QD-bR electrodes capable of harnessing the FRET phenomena and enhancing the bR electrical output by nearly 300{\%}. A biosensing prototype system was created where the target molecule disrupts the QD-bR FRET relationship and is signaled by an altered bR electrical output. With an integrated TiO$_{2}$ electron generating substrate, the QD-bR hybrid functions as a sensitizer in a thin film bio solar cell design.