Fullerene carbon dot catalytic amplification-aptamer assay platform for ultratrace As+3 utilizing SERS/RRS/Abs trifunctional Au nanoprobes

Under microwave conditions, Au-doped carbon dots (CDAu) were prepared using fullerene as a precursor, and characterized in details. It is found that CDAu can strongly catalyze the reaction of HAuCl4-fructose to generate gold nanoparticles (AuNPs). The new nanocatalytic reaction was studied by surface-enhanced Raman scattering (SERS), resonance Rayleigh scattering (RRS) and absorption (Abs) spectrometry. Based on the specific aptamer (Apt(As))-As+3 reaction mediated the CDAu-HAuCl4-fructose nanoreaction, and the products of AuNPs as SERS/ RRS/Abs trifunctional indicator nanoprobes, a new trimode Apt assay strategy was developed for detection of ultratrace As+3. A 0.07-0.70, 0.10-0.60 and 0.20-0.70 mu g L-1 were determined by SERS, RRS and Abs, with detection limits (DL) of 0.04, 0.06, 0.10 mu g L-1 respectively. The aptamer-regulation CDAu catalytic amplification platform can be also used to assay 1.7-13.3 nmol L-1 Pb2+ and 2.0-12 mu mol L-1 Hg2+, with DL of 0.80 nmol L-1 and 0.90 mu mol L-1 respectively.

Automated summary

The study demonstrated the strong catalytic ability of Au-doped carbon dots synthesized using fullerene as a precursor under microwave conditions for generating gold nanoparticles. A new trimode Apt assay strategy was developed for detecting ultratrace As+3 based on the nanocatalytic reaction, which was characterized using multiple spectroscopic techniques. The aptamer-regulated CDAu catalytic amplification platform also proved effective in detecting Pb2+ and Hg2+ with good sensitivity.