Carbon dot capped gold nanoflowers for electrochemiluminescent aptasensor of thrombin

A simple method has been developed to synthesize carbon dot capped gold nanoflower (CD/AuNF) nanohybrids. In principle, anodic electrochemiluminescent (ECL) carbon dots (CDs) with a lot of reductive functional groups were used to react with oxidative hydrogen tetrachloroaurate trihydrate in the presence of trisodium citrate. The obtained globular CD/AuNF nanohybrids had uniform sizes of 50 -60 nm. The CD/AuNF nanohybrids were composed of gold nanoparticle aggregates in the centers and CDs on the surfaces. The easy self-assembly with some bio-molecules of AuNFs and the unique ECL activities of the CDs, made the obtained CD/AuNF nanohybrids promising in biosensing. For instance, a novel ECL aptasensor for thrombin (TB) detection has been developed based on the CD/AuNF nanohybrids. The aptasensor showed good selectivity towards TB. Furthermore, it presented a wide linear response range from 0.5 nM to 40 nM and a low detection limit (S/N = 3) of 0.08 nM. (C) 2017 Elsevier Ltd. All rights reserved.