Self-enhanced luminescence of copper nanowires combined with pH-sensitive glycosyl imprinted polymers: Electrochemiluminescence for high-sensitivity detection of sialic acid.

It is of great significance to explore a low cost and high sensitivity sialic acid (SA) detection method for early diagnosis and prognosis of cancer. Electrochemiluminescence (ECL) has aroused many scholars' interest in the accurate analysis of multi-domain analytes for its excellent performance. In order to improve the ECL signal strength and the corresponding detection sensitivity, it is effective to develop new ECL reagents. Copper nanowires (CuNWs) as luminophor has always been a blank in the field of ECL sensors. In this study, a glycosyl imprinted electrochemiluminescence sensor (GIP-ECLS) for SA specificity detection in serum was developed using CuNWs as luminophor. CuNWs can not only form quasi-three-dimensional (3D) conductive network, but also realize self-enhancement of ECL signal through Cu2+ and Cu+ conversion. In addition, the excellent conductivity and wrapping properties of Ti 3 C 2 provide a large electroactive area for electrode modification. More importantly, 3-aminobenzenoboric acid (3-ABA) specifically binds to SA to form B-N or B-O, which lays the foundation for selective recognition of SA. Under optimal conditions, the signal response of GIP-ECLS showed a good linear relationship with SA concentration at 5 × 10−12–1 × 10−8 mol L−1 (R 2 = 0.997), and the limit of detection (LOD) was 1.17× 10−12 mol L−1. The results showed that in the actual sample analysis, the recovery rate of SA detected by GIP/Ti 3 C 2 /CuNWs/GCE was good, and it had good selectivity and stability, which provided ideas for designing minimally invasive and highly sensitive detection of SA in serum samples. [Display omitted] • An ECL sensor system with high selectivity was constructed for the detection of SA. • CuNWs has been reported for the first time to achieve self-enhancing ECL signals. • Ti 3 C 2 provided an effective specific surface area for the loading of CuNWs. • Glycosyl imprinting based on borate bond improved the selective detection of SA. [ABSTRACT FROM AUTHOR]