Development And Photothermal Charaterization Of Novel Two-dimensional Antimony Selenide Nanosheets

Among the cancer treatment methods,the traditional treatment methods?e.g.,chemotherapy,surgery and radiotherapy?may bring drug resistance,high probability of recurrence and metastasis.This not only decreases the efficiency of tumor therapy but also leads to other side effects.Photothermal therapy?PTT?is a mild,non-invasive therapy method,it depends on the photothermal conversion agents to convert light energy into heat,and rapid temperature increase of tumor regions can kill the cancer cells,thereby achieving laser-targeted tumor treatment.Emerging photothermal conversion nanoagents with the enhanced permeability and retention effect?EPR?of solid tumors can passively target enrichment at tumors.This could high effectively eliminate tumors without accidental damage to normal cells in a wide range.This method can attain a high anticancer efficiency with low dosage,and low toxicity and side effects.Besides,bacterial infection is also a common risk during tumor treatment process,especially at the incurred tumor incisions,the growth and proliferation of bacterial has long-time chronic accumulated stimulations of host cells,which greatly weaken the therapy effects,and even lead to metastasis and recurrence of tumors.It's of great significance by using the photothermal properties of the nanoagents to kill the bacteria.The main contents and results of this research are as follows:Based on the approach of cryo-pretreatment in liquid nitrogen and liquid-phase exfoliation?LPE?,with Polyvinyl pyrrolidone?PVP?assisted LPE,Sb₂Se₃?a semiconductor material with high biocompatibility and low costs?nanosheets with atomic thickness were developed as 2D photothermal agents with high performance.Due to its passive targeting to solid tumors,it could enrich in the tumors and target to eliminate tumors with NIR.When cultured with bacteria,PVP-capped Sb₂Se₃nanosheets showed internal long-time antibacterial ability.Strong light absorption capacity and high photothermal conversion efficiency could be observed under near NIR laser,which could be used for high temperature sterilization within a short time.Since Sb₂Se₃nanosheets had a synergistic mechanism of antibacterial and anticancer,at the same time,elimination of tumors and antibacterial effects on surgical incisions could be attained.Photothermal therapy does not lead to drug resistance,which is especially effective with multidrug-resistant bacterial.Besides,Sb₂Se₃nanosheets has inherently biocompatibility,with the modification of biological inert PVP,modified Sb₂Se₃nanosheets has blood safety,good biological compatibility and vivo stability.With all the results,this research investigated the preparation process and photothermal properties of atomically thin Sb₂Se₃nanosheets,which were developed as a highly effective photothermal conversion nanoagent for the treatment of various pathogenic bacteria infections and the photothermal ablation of solid tumour.Besides,the experimental results in vivo and in vitro indicated Sb₂Se₃nanosheets has high biocompatibility and fine prospects of biological applications.