Application Of Carbon Dots In Proteins Delivery And PH Sensing

Carbon dots(CDs)have been diffusely applied in nanomedicine,sensing,bioimaging,anti-counterfeiting,fluorescent ink etc.,benefiting from the excellent advantages of favorable optical performance,easy synthesis and functionalization and good cell permeability.In this paper,two kinds of fluorescent CDs with different functions were synthesized by hydrothermal method and successfully applied to intracellular delivery of proteins and p H sensor in organisms.The main research contents include:CDs for intracellular protein delivery were synthesized from gallic acid and L-Lysine.CDs were used as carriers to assemble with bovine serum albumin(BSA),enhanced green fluorescent protein(EGFP)and glucose oxidase(GOx)via supramolecular interaction to construct CDs-protein nanocomposites CDs-BSA,CDs-EGFP and CDs-GOx.CDs-EGFP and CDs-GOx can achieve intracellular protein delivery and CDs-GOx can maintain 89%of the biological activity of GOx.This work proves that CDs can be used as a general platform for effective intracellular protein delivery.Green fluorescent CDs were synthesized from perylene-3,4,9,10-tetracarboxylic dianhydride and citric acid.Due to it is high fluorescence quantum yield(71.4%),high selectivity,unique photostability,sterling biocompatibility and appropriate p Ka,CDs can be used as p H sensitive fluorescent probes to quantitatively detect the fluctuation of p H in living cells,zebrafish,mice and tumor tissues in real time.