Dual-quenching electrochemiluminescence resonance energy transfer system from Ru–In2S3 to α-MoO3-Au based on protect of protein bioactivity for procalcitonin detection

Abstract Herein, a highly efficient dual-quenching biosensor based on electrochemiluminescence resonance energy transfer (ECL-RET) is designed utilizing Ru–In2S3 as ECL acceptor and α-MoO3-Au as ECL donor. Compared α-MoO3-Au with pure α-MoO3, the overlapping peak area between ECL emission of Ru–In2S3 and UV–vis spectra of α-MoO3-Au is increased, indicated better quenching effect is obtained. Hollow In2S3 and α-MoO3-Au both have huge specific surface area to host a large amount of luminophores and antibodies. Moreover, HWRGWVC (H7) as specific capturer is adopted to achieve site-oriented antibody immobilization, which not only maintain antibody activity, but greatly improve the incubation process of antibodies, thus promoting the sensitivity of the biosensor. It's worth mentioning that the effect of over-potential on protein activity was proved in this work. The proposed biosensor obtained sensitive response by using PCT as a target with wide linear range from 0.0001 to 50 ng/mL and low detection limit of 12.49 fg/mL (S/N = 3), indicating its potential in the detection of biomarkers. Importantly, a novel ECL-RET pair of Ru–In2S3 (donor)/α-MoO3-Au (acceptor) is firstly developed, which opened an efficient way for highly sensitive detection of antibody in disease clinical and diagnosis analysis.