A molecule-imprinted electrochemiluminescence sensor based on Au-g-C3N4 NS nanocomposite for detection of folic acid

As a new type of two-dimensional semiconductor nanomaterials, graphite-phase carbon nitride nanosheets(g-C3N4 NS) have attracted much attention in the field of electrochemiluminescence(ECL) sensing due to their excellent ECL performance and excellent film forming properties. However, the ECL signal generated by g-C3N4 NS is unstable at higher operating voltages. The introduction of gold nanoparticles(Au NPs) can significantly improve the luminescence stability. Accordingly, Au NPs were introduced into g-C3N4 NS through in situ growth to obtain Au-g-C3N4 NS which was fixed on the electrode as the ECL substance. Meanwhile, a molecularly imprinted polymer(MIP) with specific recognition ability was introduced to construct a MIP-ECL sensor for detecting folic acid (FA). The sensor showed a high selectivity and sensitivity to FA. The ECL signal showed a good linear relationship with FA concentration in the range of 1.0×10-10-1.0×10-3 mol·L-1, and the limit of detection(LOD) was 0.07 nmol·L-1. The sensor was used to detect folic acid in the samples, and satisfactory results were obtained.