Electrochemiluminescence immunosensor based on graphene oxide nanosheets/polyaniline nanowires/CdSe quantum dots nanocomposites for ultrasensitive determination of human interleukin-6

Graphical abstract: Scheme of multistep synthesis of hybrid GO/PANi/CdSe QDs nanocomposites (A) and the fabricating steps of the ECL immunosensor (B). -- Abstract: A novel graphene oxide nanosheets/polyaniline nanowires/CdSe quantum dots (GO/PANi/CdSe) nanocomposites are successfully synthesized and use as ECL immunosensor for detection of human interleukin-6 (IL-6). The as-prepared GO/PANi/CdSe nanocomposites show excellent biocompatibility, dispersity and solubility. Electrochemiluminescence (ECL) of CdSe quantudm dots (QDs) was greatly enhanced by combining with GO/PANi nanocomposites. Herein, this GO/PANi/CdSe nanocomposite was applied to develop an ultrasensitive ECL immunosensor for detection of IL-6. The ECL immunosensor has a sensitive response to IL-6 in a linear range of 0.0005–10 ng mL−1. The prepared ECL immunosensor exhibits high specificity, long-term stability and excellent reproducibility with a detection limit of 0.17 pg mL−1