The Application Of Optical Imaging And Cancer Treatment Based On MnOx Nanomaterials

With the aging of the global population,cancer has become one of the diseases that seriously threaten human health.At present,nanomedicine that combines nanotechnology and cancer treatment has been successfully applied to the cancer diagnosis and treatment,but the research on cancer mainly focuses on treatment and imaging,and it is not common to report on the evaluation of treatment effects through imaging.Real-time monitoring of the effect of tumor treatment can immediately evaluate the treatment plan and improve it.Therefore,in order to achieve the purpose of multi-mode imaging and combined therapy of nanomaterials on tumors and monitoring the therapeutic effect through imaging,we have done the following work.The research content of this paper is mainly divided into the following three parts:(1)To accurately assess the catalytic activity of nanomaterials and achieve the diagnosis and treatment of cancer,we developed a new type of manganese-based polymer nanocomposite PFODTBT@MnOx@IR775S@PEG(MSPN),which can monitor nanoenzyme catalytic activity in acid-induced cancer treatment in real time through ratiometric near-infrared fluorescence(NIRF)-photoacoustic(PA)imaging.We combined the polymer semiconductor nanomaterial PFODTBT covalently linked to IR775S(a near-infrared dye responsive to reactive oxygen species)and MnOx nanoenzymes to synthesize nanoparticles.This nanoparticle can achieve ratiometric NIRF-PA imaging at the tumor site,and at the same time,MnOx generates highly toxic singlet oxygen(¹O₂)in response to acid to achieve efficient tumor killing.In short,the nanoparticle can realize ratio NIRF-PA imaging through acid response to monitor the effect of cancer treatment,and provide new ideas for evaluating and predicting treatment results.(2)In order to enhance the functional diversity and therapeutic effects of nanomaterials,we successfully added the Fe Pt@MnOx nanoenzyme to the ratio-based NIRF-PA imaging system to synthesize a polymer nanocomposite called PFODTBT@Fe Pt@MnOx@IR775S@PEG(FPM).Compared with MSPN,FPM can increase the types of ROS generated in the tumor site:In the acidic conditions of the tumor microenvironment,MnOx can not only respond to acid to produce highly toxic¹O₂,but also the iron ions in Fe Pt can produce highly toxic hydroxyl radicals(.OH)through reacting with H₂O₂.At the same time,it can monitor the production of ROS through ratio-based NIRF and the treatment effect.(3)In order to further enhance the therapeutic effect of tumors,based on the good chemokinetic treatment of MnOx at the tumor site,we use the MnOx with3,3',5,5'-tetramethylbenzidine(TMB)to form MnOx@TMB nanoparticles.The nano system can produce highly toxic ¹O₂ in response to acid,and then ¹O₂ can act as a trigger of the TMB photothermal effect.Under the radiation of 808 nm laser,MnOx@TMB can realize chemodynamic therapy combined with photothermal therapy at the tumor site.Compared with a single cancer treatment,the combination therapy improves the treatment effect,and at the same time the photoacoustic signal at the tumor site is also enhanced.