Fabrication of electrochemiluminescence aptasensor based on in situ growth of gold nanoparticles on layered molybdenum disulfide for sensitive detection of platelet-derived growth factor-BB

Abstract

Molybdenum disulfide–gold nanoparticle (MoS₂–AuNP) composites were synthesized by the simple method of in situ growth of AuNPs on layered MoS₂. The MoS₂–AuNP composites were characterized by scanning electron microscopy and transmission electron microscopy. The results showed that the AuNPs were uniformly decorated on the layered MoS₂. A sandwich ECL aptasensor was fabricated via layer-by-layer assembly for detection of platelet-derived growth factor BB (PDGF-BB) using MoS₂–AuNP composites as a matrix and quantum dots as a signal probe. The MoS₂–AuNP composites exhibited good conductivity and enhanced the immobilized amount of aptamer1 and further generated amplified ECL signals. Under the optimal conditions, the ECL aptasensor has high sensitivity, selectivity and stability for PDGF-BB detection with a wider linear range from 0.01 pmol L⁻¹ to 100 pmol L⁻¹ and a lower detection limit of 1.1 fmol L⁻¹ (S/N = 3). Moreover, the aptasensor has been used for the determination of PDGF-BB in human serum samples with recoveries of 88.0–100.1% and RSDs of 1.6–4.3%. This work paves a novel way for functionalization of MoS₂ with AuNPs and provides a promising strategy for the development of various ECL aptasensors.