Microwave synthesis of chitosan-based carbon dots for Al3+ detection and biological application

Yellow fluorescent carbon dots (Y-CDs) were prepared via microwave method using chitosan and o -phenylenediamine as the main raw materials. The obtained Y-CDs possesses good water solubility, excellent biocompatibility and luminous stability. During the microwave pyrolysis carbonization process, the surface of Y-CDs was modified with the functional groups such as amino and carboxyl, which can bind to Al 3+ by forming complexes, further improving the selectivity and sensitivity of the Al 3+ detection. And the fluorescence of Y-CDs was quenched by Al 3+ by static quenching process. More importantly, Y-CDs as fluorescent sensor was further applied for the determination of Al 3+ in the real water samples with high reliability and accuracy. In addition, Y-CDs present potential application in biological imaging. The cultivated zebrafish embryos with Y-CDs displayed clearly in vivo uptake and metabolic fluorescence images, further confirming its low toxicity and excellent biocompatibility.