Photoelectrochemical sensing for microRNA based on semiconductor nanomaterials

• 1、School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023

Abstract： We construct a near-infrared light of photoelectrochemical sensor to detect microRNA based on semiconductor nanomaterials. Lead sulfide/ lead iodide is a novel compound semiconductor nanomaterials, which can be excitated by a long wavelength light, and it owns a lots of merits including a stable current signal and good reproducibility. In addition, the designed method can simplify the operating conditions,and it is not essential to add ascorbic acid as an electron donor .At the same time in the condition of N2 atmosphere is not required, which provides a new way to design a quick and easy photoelectrochemical sensor devices, greatly improving experimental work efficiency and reducing the cost of experiments. The designed strategy utilizes complementary base pairing, resonance energy transfer and competition law. Because gold nanoparticles can improve the separation efficiency of light electrons and photogenerated holes and generate surface plasmon resonance, helperDNA labeled with gold particles make a pair with probeDNA resulting in the reduce of photoelectric signal. MicroRNA hybridizes with the probe DNA which make the Au-helperDNA drop off so that the light current increases. Using the changes of photocurrent signals to build a common platform photoelectrochemical sensor for detecting microRNA. Photoelectrochemical sensor constructed for the detection of microRNA has a wide linear range and high selectivity.

Keywords： Analytical chemistry DNA sensor MicroRNA detection Semiconductor Gold nanoparticles