Construction And Application Of Multi-Stimulated Response Drug Delivery System

Cancer all the time does not affect people's physical and mental health,how efficient,low side effects of cancer treatment is the world's common face medical problems.Now the treatment is extremely limited,more effective research and development,le SS toxic side effects of treatment has become an inevitable trend.In the past ten years,nano-micellar drug carrier has become a practical value of the study,which has di SSolved more drug small molecules,good biocompatibility,lower toxic side effects,longer in vivo circulating release time and the ability to target cell therapy and so on.Based on the existing research work,this paper further studies and modifies the p H-responsive drug delivery system-poly-histidine to solve the problem that the oilsoluble anti-cancer small molecule is difficult to circulate in the body and the low cell uptake rate.Polyphosphine(PHis)is a neutral hydrophobic,acidic hydrophilic polymer and has the characteristics of proton sponge,biocompatibility,increased endocytosis,etc.The polyethylene glycol(m PEG)can confer polymer PHis-b-m PEG is better biocompatible,and the anthocyanin near-infrared photothermal small molecule Cypate is wrapped in micelles to give m PEG-b-PHis polymer micelles photothermal response,coated with adriamycin Then,the particle size and appearance of the drug carrier nanoparticles were characterized by dynamic light scattering(DLS)and transmi SSion electron microscopy(TEM).After the in vitro release experiment,it showed that the drug-loaded micelles had good neutral stability and could release the drug in acidic environment.In this work,PNIPAM was synthesized by atom transfer radical(ATRP)polymerization,and a series of functional groups were obtained to obtain the disulfidetype polymer PNIPAM-SS-BOC with glutathione(GSH)And PNIPAM-SS-PCL amphiphilic polymer was obtained by enzymatic open-loop method using amino-ringopening ?-caprolactone to PNIPAM-SS-NH2.The particle size and appearance of the drug carrier nanoparticles were characterized by dynamic light scattering(DLS)and transmi SSion electron microscopy(TEM)after the polymer was coated with adriamycin.After the in vitro release experiments were carried out,indicating that the polymer nano-micelles can respond to the temperature change stimulus,the release of drugs.In this work,a new type of controlled polymerization method such as ATRP and enzymatic ring-opening polymerization was used to design and synthesize a simple proce SS,low cost,green pollution,high conversion rate,structural design and molecular weight control Of nano-micelles drug-loaded polymers.In addition,the introduction of some special properties of small molecules or functional groups to the polymer micelles or segments,simplifying the operation,improve the degree of flexibility,to achieve multiple stimulus intelligence response,diagnosis and treatment integration.In summary,the work of this paper has a potential application value for the construction of multi-stimulating response nano-drug carrier and anti-cancer research,and has contributed a certain force in the history of human anticancer struggle.