High-Efficiency CdSe Quantum Dots/Fe₃O₄@MoS₂/S₂O₈^2- Electrochemiluminescence System Based on a Microfluidic Analysis...

In this work, based on electrochemiluminescence (ECL) technology and self-assembled portable disease detection chips, a bioactivity-maintained sensing platform was developed for the quantitative detection of neuron-specific enolase. First, we prepared Fe₃O₄@MoS₂ nanocomposites as an efficient catalyst to accelerate the reduction of persulfate (S₂O₈^2-). Specifically, abundant sulfate radicals (SO₄^•-) were generated because of cyclic conversion between Fe²⁺ and Fe³⁺. Meanwhile, MoS₂ nanoflowers with a high specific surface area could not only load more Fe₃O₄ but also solve its agglomeration problem, which greatly improved the catalytic efficiency. Moreover, a biosensor chip was constructed by standard lithography processes for disease detection, which had good sensitivity and portability. According to the above strategies, the developed portable sensing platform played the part of promoting the practical application of bioanalysis in early tumor screening and clinical diagnosis. In addition, we developed a short peptide ligand (NARKFYKG, NAR) to avoid the occupation of antigen binding sites by specifically connecting to Fc fragments in antibodies. Thus, the binding efficiency of antibodies and the activity of biosensors were improved due to the introduction of NAR.