Low-potential bionic electrochemiluminescence sensing platform based on SnS₂/CuNWs synergistic promotion for highly selective detection of glycocholic acid

Background: Glycholic acid (GCA) can dynamically reflect the process of liver injury, and can be used for early diagnosis and curative effect evaluation of early hepatitis and cirrhosis. The highly sensitive detection of liver injury markers is conducive to a more accurate and effective auxiliary diagnosis of liver diseases. In addition, the low trigger potential helps to avoid more chemical interference and improve the detection sensitivity. It is of great significance to develop a high sensitive and low potential ECL sensor for GCA detection.

Results: In this work, a low trigger potential molecularly imprinted electrochemiluminescence sensor (MIECLS) combining SnS₂ and CuNWs was proposed for highly selective and sensitive detection of GCA, a marker of liver injury. The stabilization and enhancement of ECL signal can be attributed to the synergistic promotion strategy of SnS₂ and CuNWs. CuNWs not only has good ECL performance, but also serves as a substrate material for loading SnS₂ to enhance the film forming performance. In addition, the Sn⁴⁺ active site can be regenerated by redox reaction, significantly improving the efficiency of the co-reactant and the stability of the sensor. By studying the ECL luminescence mechanism and specific recognition quenching mechanism of MIECLS in detail, a selective detection method for GCA was established. Under optimal conditions, in the range of 5 × 10^-10 to 5 × 10^-6 mol L^-1, the quenching value of ECL intensity is proportional to LgC_GCA, and the limit of detection is 1.30 × 10^-10 mol L^-1.

Significance and novelty: In addition, satisfactory recovery rate was obtained in human serum samples, showing good practical application, providing a new way for clinical detection of GCA. At the same time, it not only broadens the development of CuNWs in the ECL field, but also provides a new way to reduce the triggering potential.