Construction Of Quantum Dot-based HA Gel Sensor And Its Application In Tumor Microenvironment

Cancer is one of the major diseases that seriously threaten human health.The precise treatment of cancer has become an important issue to be solved urgently in the medical community.Cisplatin is widely used as a chemotherapeutic agent in cancer.However,the complex environment of tumor formation and drug resistance make cisplatin highly effective and precise for anticancer treatment.In this paper,based on the interaction of quantum dots(QDs)and cisplatin prodrugs(CDDP),cisplatin and DNA,a simple two-way fluorescence ―on-off‖ hydrogel sensor is constructed,which can Platinum anti-cancer drugs are monitored and traced in real time to achieve precise treatment of tumor drugs.The sensor developed in this research not only overcomes the selectivity problem in traditional unidirectional fluorescence detection,but also provides new ideas and methods for real-time monitoring and precise treatment of tumor drugs.The main contents include:(1)Synthesis of CdTe quantum dots: The research discusses the influence of pH,reaction time,reaction temperature,the ratio of 3-mercaptopropionic acid(MPA)to cadmium,the ratio of cadmium to tellurium on its properties;through the characterization of quantum dots,comprehensive analysis is The best process conditions for the preparation of CdTe quantum dots;(2)Synthesize cisplatin prodrug and use it as a crosslinking agent to synthesize hyaluronic acid gel,explore the optimal ratio of hyaluronic acid and crosslinking agent in gel formation,and use hydrogel as a drug carrier Cell experiment,CCK8 experiment proves that this hydrogel drug carrier has better antitumor effect than free cisplatin.(3)The cisplatin prodrug can quench the fluorescence of MPA-CdTe QDs by photoinduced electron transfer;while the tumor microenvironment is rich in glutathione(GSH),the cisplatin prodrug is reduced to cisplatin,cisplatin and Covalent binding occurs between DNA,which leads to the recovery of quantum dot fluorescence.A simple two-way fluorescence "on-off" sensor is constructed for real-time monitoring of anticancer drugs in the tumor environment,while detecting cisplatin prodrugs and DNA concentration.In this sensing system,the fluorescence intensity of MPA-CdTe QDs was quenched by hyaluronic acid-cisplatin prodrug(HA-CDDP)gel standard solutions of different concentrations and the fluorescence intensity of MPA-CdTe QDs by DNA standard solutions For the detection of recovery change,it is calculated that the relative fluorescence intensity quenching change has a good linear relationship with the cisplatin prodrug concentration,and the relative fluorescence intensity recovery change has a good linear relationship with the DNA concentration.The linear correlation coefficient of fluorescence quenching is 0.9997,the linear correlation coefficient of fluorescence recovery reached 0.9998.At the same time,the sensor shows a wide detection interval and a low detection limit,which has certain practical application significance.