Nanocomposites prepared from gold nanowires and multiwalled carbon nanotubes for non-enzymatic sensitive bioelectrochemical detection of pentraxin-3 in human serum

Abstract

Pentraxin-3 (PTX-3) is one of the newly discovered tumor biomarker, especially in the diagnosis of lung cancer. The functionalized multi-walled carbon nanotubes (MWCNTs) and gold nanowires (AuNWs) nanocomposites decorated the PTX-3 biosensor were reported in this work, realizing ultrasensitive detection of PTX-3 in human serum through simple and effective non-enzymatic reaction. The PTX-3 biosensor has excellent electrochemical activity and biocompatibility through carbon and metal nanomaterials. Compared with pure MWCNTs, the MWCNTs combined with AuNWs which shows a wide range of detection (0.001–1000 ng ml-1), higher sensitivity (17.10 μA/(ng ml-1)/cm2) and lower detection limits (0.16 pg ml-1, S/N = 3). Meanwhile, gold nanomaterials are one of the most stable noble metal nanomaterials and MWCNTs possess large electroactive surface area, which can greatly improves the stability (96.3%, after 3 weeks) and repeatability (RSD = 0.51%). This work remarkably extends the utilization of MWCNTs and AuNWs in the construction of biosensors in the fields of biosensing and medical diagnosis.