Preparation And Properties Of A Multifunctional Carbon Dot-Based Drug Delivery System

As a novel delivery system, the Drug Delivery Systems(DDSs) based on nanoparticles has mang advantages, such as stimuli responsive, targeting therapy, imaging and tracking drugs, thus it has attracted great attentions in anti-cancer field. In this study, we chose Doxorubicin hydrochloride as a model drug, Carbon dots as a drug carrier, Folic acid as a targeting group, designed and prepared a multifunctional drug delivery system with p H-triggered drug release.The main research work and results of this paper are as follows:(1) The amino-coated fluorescent Carbon dots is prepared by microwave. The Carbon dots has many excellent properties, such as: good water solubility, uniform particle distribution, low cell toxicity and good biocompatibility. What’s more, it can be used as a carrier for drug delivery systems, and has good potential and applications in biological nanoparticle drug delivery system.(2) We designed and prepared the multifunctional nano drug delivery system DOX-CDots-FA based on the prepared Carbon dots. The structure of all the intermediates and final products are characterized and confirmed by 1H NMR and LCMS methods. The DOX loading of the targeted drug delivery system is about 13.5%.(3) The drug delivery system DOX-CDots-FA has a good stability, in the PBS buffer(p H=7.4), it is stable and almost no drug is released. However, in the acid buffer(p H=5.2 and p H=6.0), it will accelerate the drug release rate, which is p H-responsive. In the role of folate receptor- mediated, the cellular uptake of He La cells to drug delivery system DOX-CDots-FA is more than non-targeted drug system, indicating that the introduction of folic acid group can improve the targeting effect, and reduce the toxic side effects of the drug Doxorubicin. MTT assay showes that for He La cell(FR-positive cells), drug delivery system DOX-CDots-FA is significantly higher than non-targeted drug system, indicating that our prepared targeted drug system has higher toxicity for the FR-positive tumor cells and can achieve an effective therapeutic effect.