Guangming Nie

Electrochemiluminescence biosensor based on conducting poly(5-formylindole) for sensitive detection of Ramos cells.

A signal-on electrochemiluminescence (ECL) biosensor devoted to the detection of Ramos cells was fabricated based on a novel conducting polymer, poly(5-formylindole) (P5FIn), which was synthesized electrochemically by direct anodic oxidation of 5-formylindole (5FIn). This ECL platform was presented by covalently coupling the 18-mer amino-substituted oligonucleotide (ODN) probes with aldehyde groups that are strongly reactive toward a variety of nucleophiles on the surface of solid substrates. The specific identification and high-affinity between aptamers and target cells, gold nanoparticles (AuNPs) enhanced ECL nanoprobes, along with P5FIn induced ECL quenching contributed greatly to the sensitivity and selectivity. The ECL signals were logarithmically linear with the concentration of Ramos cells in a wide determination range from 500 to 1.0 × 10(5) cells mL(-1), and the corresponding detection limit was 300 cells mL(-1).

A graphene quantum dots based electrochemiluminescence immunosensor for carcinoembryonic antigen detection using poly(5-formylindole)/reduced graphene oxide nanocomposite

A novel electrochemiluminescence (ECL) immunosensor for ultrasensitive detection of carcinoembryonic antigen (CEA) was developed using signal amplification strategy based on poly(5-formylindole)/reduced graphene oxide nanocomposite (P5FIn/erGO) and Au nanoparticle (AuNP) decorated graphene quantum dots (GQDs) (GQDs@AuNP). As an effective matrix for immobilization of primary antibody (Ab1), P5FIn/erGO nanocomposite facilitated the ion transport during the redox reactions and provided larger surface areas for the immobilization of Ab1. GQDs@AuNP was used as labels to conjugate with secondary antibody (Ab2), which improved electron transfer capability with stable ECL intensity. The multiple amplification of P5FIn/erGO and GQDs@AuNP made the ECL immunosensor have a broad linear range from 0.1pgmL-1 to 10ngmL-1 and a low detection limit with 3.78fgmL-1. In addition, this ECL immunosensor performed with admirable stability and good selectivity and reproducibility as well. When this immunosensor was used for the analysis of CEA in human serum, good recoveries were obtained. Thus, there will be a promising future in the early diagnosis of cancer to detect CEA.