Efficient Screening of nNOS-PSD95 Uncoupling Agents Based on Radiometric Fluorescent Molecularly Imprinted Sensors

Abstract

Novel and efficient ratiometric fluorescent molecularly imprinted sensors (RFMIS) based on epitopes were developed, which can be used for the sensitive detection of neuronal nitric oxide synthase in the screening of neuronal nitric oxide synthase-postsynaptic density95 (nNOS-PSD95) coupling inhibitors. Under appropriate conditions, the fluorescence of the carbon dots quenched with the increasing concentration of nNOS1-133, while the fluorescence of the quantum dots remained unchanged. The fluorescence ratio had a good linearity in the concentration range of 0-500 ng mL-1 for nNOS1-133 and the determination limit was 0.14 ng mL-1. Using the classical nNOS-PSD95 coupling inhibitor (ZL006) as a control, the RFMIS were used as the detector to detect the free nNOS released by Gnetol and 2,3,5,4ʹ-tetrahydroxystilbene-2-O-β-Dglucoside from natural medicine after inhibition of nNOS-PSD95. The results have shown that the uncoupling efficiencies was consistent with co-immunoprecipitation experiments. The study provides a new idea and a new way for efficient screening of nature nNOS-PSD95 coupling inhibitors from natural medicine with the advantages of high efficiency, sensitivity and traceability.