Synthesis And Application Of Tellurium Nanomaterials In Simultaneous Chemo-photothermal Cancer Therapy

In recent years,the morbidity and mortality of cancer are increasing year by year,which has become a major disease that seriously endangers human health.Due to the extremely complex mechanism of occurrence and development of tumor,the traditional chemotherapy and radiotherapy strategies can not effectively inhibit the malignant progression of tumor,and have great side effects to normal tissue,which seriously affect its clinical application.At present,a large number of clinical evidences demonstrate that the combined tumor treatment strategy can effectively solve the problem of poor efficacy of a single strategy.The combined application of a variety of treatment methods can not only effectively kill the tumor,but also reduce the damage to normal tissue.Therefore,it is of inestimable clinical demand to develop a new strategy of safe and effective combination of chemotherapy.With its unique advantages such as selective killing of tumor cells and low side effects,photothermal therapy(PTT)based on nanomaterials exhibits a good application prospect in tumor therapy.Studies have shown that PTT combined with chemotherapy can improve cell membrane permeability and reduce the dosage of chemotherapeutic drugs.However,at present,the preparation process of tumor photothermal-chemotherapy system based on nanomaterials is relatively complex.Additionally,the photothermal conversion efficiency,photostability and the toxicity of nanomaterials to normal cells and tissues need to be further improved.However,the limitation of clinical application of PTT is mainly due to a variety of practical difficulties,the most important of which is how to fully heat the tumor and strict requirements for nanomaterials.Therefore,the development of tumor photothermal-chemotherapy combined therapy nano-system with simple structure,convenient preparation,effective combination of PTT and chemotherapy and safe and effective has become a key problem to be solved in this field.tellurium(Te)nanomaterials have good responsiveness to NIR,high photothermal conversion efficiency,and no disadvantages of photobleaching.Therefore,in this study,functionalized rambutan-like Te nanosystem(DOX/PEI@TeNPs)was prepared and its anti-tumor activity was investigated.The specific results are as follows:In this study,we design a functionalized Te-based nanosystem,with one-step synthesis of shape control,good photothermal conversion efficiency,and good light stability,which can be used to encapsulate chemotherapeutic drugs under mild hydrothermal conditions.Our results showdemonstrate that the morphology of DOX/PEI@TeNPs is controllable and its special rambutan morphology is due to the formation of hydrogen bond between PEI and DOX and the growth of tellurium nanorods in situ.The synthesized Te nanorods have good photothermal conversion efficiency and good photostability because of their strong NIR absorption.Under the stimulation of 808 nm NIR,Te nanorods wrapped in DOX/PEI@TeNPs system convert light energy into heat energy,and effectively kill tumor cells by inducing excessive production of ROS in tumor cells.At the same time,NIR laser destroyed the hydrogen bond between DOX and PEI in Te nano-rambutan,then the DOX in nano-rambutan was released to further kill tumor cells.To sum up,DOX/PEI@TeNPs under NIR laser irradiation can not only produce effective heat to kill tumor,but also promote the release of drugs in tumor tissue.It shows that DOX/PEI@TeNPs is a new and effective nanomaterial for tumor photothermal combined with chemotherapy,which improves the photothermal conversion efficiency of common photosensitizers,which often requires high dosage of photothermal agents,high light intensity and long NIR stimulation time,and expands the application of Te nanomaterials in PTT and drug delivery.Therefore,this study provides an effective strategy for the delivery design of nano-drugs,which can be used for accurate chemo-photothermal synergistic therapy of tumors.