Study Of NIR-light-sensitive Hydrogels And Nanoparticles For Cancer Diagnosis And Therapy

Among a variety of externally controllable stimuli?such as light,magnetic fields,and ultrasound?,near-infrared light?NIR?has less damage to tissue and deeper penetration depths,and can be easily and accurately controlled in space and time.Therefore,the materials within the NIR response range are receiving more and more attention.In recent years,tumor treatment and diagnostic systems have been developed for the advantages of NIR-responsive materials.These NIR-responsive materials can convert NIR into localized heat to kill tumor cells and quantify photothermal effects by photothermography.Based on this,this article is aimed at NIR-responsive materials,on the one hand,indocyanine green?ICG?was introduced into the supramolecular hydrogel to construct a light-controlled disassembly of drug precise release system for tumor chemo-photothermal combination therapy;on the other hand,based on thermal imaging of functionalized polydopamine nanoparticles?PDA?enables rapid detection of tumor cells.The specific research content is mainly divided into the following two aspects:1.A light-controlled disassembly of supramolecular hydrogel for tumor chemo-photothermal combination therapyAt present,hydrogels for drug carriers often only serve as sustained release.In order to achieve accurate space-time delivery of anticancer drugs,an injectable,self-healing,remote controlled light-degradable hydrogel has been prepared,which is used for local chemo-photothermal treatment of tumors.The supramolecular hydrogel is prepared by a ferrocene-modified HA?guest macromonomer,HA-Fc?and a?-cyclodextrin-modified HA?macromer macromonomer,HA-CD?through a guest-body interaction,and it is coated with the photosensitizer phthalocyanine green?ICG?and the chemotherapy drug doxorubicin?DOX?.Under the near-infrared illumination,the ICG releases heat and singlet oxygen?¹O₂?simultaneously,and singlet oxygen achieves disassembly of the hydrogel by oxidizing Fc,then causing release of the loaded Dox.Thereby achieving on-demand release under near-infrared illumination.The vitro experiments confirmed that the light-controlled disassembly of hydrogels not only have excellent photothermal effects,but also exhibit controlled-release of the therapeutic drug Dox and long-term effective inhibition of tumor cell,as well as excellent cell and blood compatibility.In vivo results further confirmed the ability of light-controlled disassembly,controlled-release of Dox,effective anti-tumor and prevention of recurrence,and lower toxic side effects in mice by multimodal imaging?fluorescence,CT and photoacoustic?.This light-controlled disassembly of hydrogel provides a solution for accurate remote controlled-release of drug in vivo,which will be promising for topical treatment of various diseases,enhancing the treatment effect and reducing side effects.2.Rapid and Sensitive Detection of Cancer Cells Based on the Photothermal Effect of RGD Functionalized PolydopamineAn RGD-modified polydopamine?PDA?nanoparticle was prepared for sensitive,rapid,and in situ tumor cell thermography detection.In this study,combining the thermal effects of infrared thermal imaging and PDA to create a portable sensor device and optimizing the relevant parameters,it can simultaneously achieve efficient capture of cancer cells and high sensitivity thermal contrast detection.Using the correlation curve between temperature changes caused by near-infrared light and the number of cancer cells,the sensitivity of tumor cell detection is highly sensitive in the range of 0-2.5 million cells.The results provide a target cell thermal imaging assay based on photothermal effects of PDA.