| Currently,cancer remains one of the most threatening diseases facing mankind and its treatment options include surgery,radiotherapy,chemotherapy,immunotherapy,phototherapy and targeted therapy.Among these,photothermal therapy（PTT）and photodynamic therapy（PDT）are considered promising cancer treatment modalities due to their less invasive nature and high spatial and temporal precision.However,the efficacy of a single treatment approach is often limited by the complex tumour microenvironment,so PTT is often combined with PDT to improve treatment outcomes.In addition,during combination therapy,the thermal energy generated by PTT not only promotes blood flow within the tumour and elevates the oxygen level within the tumour,but also enhances the absorption of photosensitizers（PSs）by the cells,thus significantly improving the anti-cancer treatment effect.However,in terms of clinical results,light combination therapy cannot completely eradicate tumours with recurrence.Therefore,many scholars are committed to improving the effectiveness of tumour treatment by combining chemotherapy and phototherapy.Adopting the idea of integrating phototherapy and chemodynamic therapy（CDT）to achieve a safe and efficient cure for tumours,improve patient survival and reduce recurrence rates.Among them,nano-antitumour drugs have attracted attention due to their good damage specificity,efficient bioavailability,excellent bioactivity and low side effects.In the past decades,organic-inorganic composite nanomaterials have been widely used in clinical cancer treatment due to their structural and functional versatility.Among them,metal-organic frameworks（MOFs）with their special tunable porous structures can be used not only in catalysis,selective adsorption and separation,and gas storage,but also in bio-nanomedicine fields such as drug delivery and bio-imaging.In addition to their direct involvement in the construction of antitumour agents,MOFs can also serve as precursors/templates for many emerging MOF-derived nanomaterials（mesoporous carbonaceous materials,nanoenzymes,etc.）.Therefore,it has high potential for antitumor applications.In this work,three types of metal-doped organic framework-derived materials were designed and synthesized based on existing reports and studies,and the best photothermal/photodynamic synergistic tumour treatment was obtained by modulating the carbonation temperature and metal ion doping content,as well as comparing the photoconversion efficiency and the rate of reactive oxygen generation of the synthesized materials.The above materials were then loaded with Adriamycin（DOX）,followed by polymeric coating with Dopamine（DA）,and in vitro experiments showed better photothermal conversion performance and investigated the synergistic effect of intracellular light/drug therapy.The main elements are as follows:（1）An Fe-atom-doped organic skeleton-derived mesoporous carbon material（Fex-N-CT）with porphyrin-like properties was successfully prepared by high-temperature carbonisation of Fe-ZIF-8 precursors.During the carbonisation process,the doped iron nitrate nine-hydrate not only created Fe atomic active sites on the ZIF-8-derived carbon skeleton,but also modulated the pore size morphology of the carbon-based material.The effects of different Fe atom doping contents and pyrolysis temperatures on the morphology,structure and PTT/PDT of Fex-N-CT materials were then investigated.It is shown that the Fe50-N-C900 material exhibits excellent PTT/PDT properties under single wavelength NIR light（808 nm）irradiation in a hydrophilic environment.Furthermore,Fe50-N-C900 has ability to generate 1O2 in live tumour cells and induce massive apoptosis in tumour cells under single wavelength NIR laser irradiation.（2）Two types of metal-doped organic skeleton-derived mesoporous carbon materials were successfully synthesised by a mild,simple and green aqueous-phase reaction:one type of MOF mesoporous carbon（Ruy-N-C）with a single doped metal ruthenium;the other type of Fe and ruthenium bimetallic doped organic skeleton-derived mesoporous carbon material（Fe-Ru-N-C）.The effects of the two types of materials on PTT and PDT were investigated experimentally.The effect of varying the different doping content ratios of metals Fe-and Ru on the structural morphology of Fe-Ru-N-C materials and the therapeutic effect on cancer was investigated.It is shown that Fe-Ru-N-C induces tumour cell death significantly better than non-irradiated cells under single wavelength NIR laser irradiation in a hydrophilic environment,as well as showing the best PTT/PDT performance under single wavelength NIR light(808 nm,1 W·cm-2)irradiation.（3）In order to improve the tumor treatment effect and compensate for the shortcomings of the repetitive nature of phototherapy,DOX/Fe-Ru-N-C@PDA composites with core-shell structure were designed and prepared.The material can effectively enter cancer cells and successfully release DOX in a specific tumor acidic environment to efficiently inhibit the proliferation of Hela cells.In addition,the PDA coating can enhance the photothermal conversion efficiency and allow DOX to be released slowly.Cytotoxicity experiments showed that DOX/Fe-Ru-N-C@PDA composites are cytocompatible and have good effect of combined photo/pharmaceutical therapy.Finally,the morphology of three different MOF-based derived mesoporous carbons and their cancer treatment effects are specifically described and analysed,and further perspectives on the treatment of the three MOF-derived composites are made based on the experimental results. |
