Rapid synthesis of B-N co-doped yellow emissive carbon quantum dots for cellular imaging

In order to avoid the interference of autofluorescence and improve tissue penetration capability of carbon quantum dots (CQDs) in biological imaging, the synthesis of long-wavelength emission CQDs was achieved in this work. Boron and nitrogen co-doped CQDs (BN-CQDs) were synthesized by one-step microwave assisted hydrothermal method with o-phenylenediamine as carbon and nitrogen source, boric acid as boron source. The BN-CQDs (QY = 13.79%) synthesized under the optimal conditions exhibit excitation independence, a large Stoke shift, satisfactory fluorescent stability, good biocompatibility and low toxicity, which can meet the basic requirements as cell imaging agent. Cell imaging measurements prove their increased intracellular accumulation with the extension of incubation time with HeLa cells, and clearly observable BN-CQDs imaging for cell morphology. Hence BN-CQDs can be used as a good cell imaging agent.