Dual-Channel electrochemiluminescence mechanism and bioanalysis of semiconductor solar cell material Cu₂ZnSnS₄

This study involved the synthesis of Cu₂ZnSnS₄ (CZTS) via a high-temperature liquid-phase strategy, followed by a comprehensive characterization of its structural and optical properties using a range of analytical techniques. The electrochemiluminescence (ECL) phenomenon of CZTS has been discovered for the first time. Moreover, the use of tripropylamine (TPrA) and persulfate (S₂O₈²⁻) as co-reactants resulted in CZTS exhibiting highly efficient ECL emission at both positive and negative potentials. The sulfur vacancies in CZTS functioned as electron traps, which enhanced the adsorption and binding affinity of co-reactant radicals. This promoted the interaction between the co-reactant and the ECL emitter, reduced energy loss, and significantly improved the ECL performance of the dual co-reactant system. In light of these findings, a new ECL biosensor was developed, incorporating DNA walker technology, an FTO three-electrode system, and enzyme-free cleavage, facilitating the efficient detection of the biomarker microRNA-141 (miRNA-141). The biosensing mechanism employed a “on-off-enhance on” signal conversion strategy, showcasing remarkable detection performance for miRNAs across a concentration range of 10⁻¹⁶ to 10⁻¹⁰ M, with a detection limit (LOD) reaching as low as 10⁻¹⁶ M. This study broads the potential applications of traditional semiconductor solar cell material CZTS within the field of ECL, offering a theoretical foundation for advancing ECL research and underscoring its applicability in biomedical research and clinical diagnosis.