生物功能化碳量子点制备

Carbon quantum dots are biofunctionalized using a covalent modification method to achieve the application of carbon quantum dots in cellular fluorescent imaging. Blue fluorescent carbon quantum dots were synthesized through the hydrothermal method using citric acid as carbon source and ethylenediamine as passivation agent. Carbon quantum dots were carbonxylized to achieve covalent coupling, followed by two-step functional molecular modification to complete the preparation of biofunctionalized carbon quantum dots. The properties and biofunctions were investigated by transmission electron microscope, fluorescence and ultraviolet spectrophotometer, infrared spectrometer, potential particle size analyzer and fluorescence confocal microscope. The experimental results show that poly(ethylene glycol) (PEG) and nuclear targeting peptide TAT (trans-activator trans-cription) are successfully modified on the carbon quantum dots via one-step amidation coupling chemistry, and folic acid (FA) is successfully modified at the end of PEG. The biofunctionalization of carbon quantum dots is prepared by two-step covalent modification. The biofunctional carbon quantum dots with neutral electrical property, small size, low toxicity, and nuclear targeting can be applied to cellular fluorescenct imaging.