Boron and Nitrogen-Codoped Carbon Dots as Highly Efficient Electrochemiluminescence Emitters for Ultrasensitive Detection of Hepatitis B Virus DNA

In this work, boron and nitrogen-codoped carbon dots (BN-CDs) as highly efficient electrochemiluminescence (ECL) emitters with advantages of low excitation potential and high ECL efficiency were prepared to establish a novel ternary ECL system for ultrasensitive detection of HBV-DNA. Especially, both platinum nanoflowers (Pt NFs) and boron radicals (B^•) from the BN-CDs could accelerate the reduction of coreactant S₂O₈^2- to abundant SO₄^•- simultaneously, making the BN-CDs have outstanding ECL performance. Impressively, the ECL efficiency of BN-CDs is much higher than that of nondoped CDs and single-doped CDs. In addition, by combining the novel ECL ternary system with the exonuclease III (Exo III)-induced target DNA amplification strategy, an ECL biosensor was constructed to realize the ultrasensitive detection of HBV-DNA from 100 aM to 1 nM, while the limit of detection was 18.08 aM. Therefore, a promising highly efficient ECL emitter was offered to develop a novel ECL detection method for clinical disease analysis.