One-pot Synthesis Of Polymers Containing Thioacetal In The Main Chain

With the increasing development of society,environmental and health issues have received increasing attention.Cancer treatment is still a major problem in public health issues.Traditional drug therapy has limited curative effect and strong side effects,mainly manifested by poor water solubility,low bioavailability,and poor target location.Drug-loaded nanocarriers have unique advantages in biomedicine application materials.Among them,amphiphilic polymers responsive to p H and ROS stimulation have been extensively studied to deliver and release therapeutic drugs or genes in tumor cells.Among environmental problems,serious diseases and environmental pollution caused by heavy metal ions have become one of the main public health problems.In particular,mercury(II),as a highly toxic pollutant,can damage the body's metabolism,central nervous system and immune system,posing a serious threat to the life system.At present,it is very important to develop ultra-sensitive probes in real-time detection and effective removal of mercury ions.However,most of the mercury ion fluorescent probes have a shortcoming in one aspect.Therefore,the use of high polymers with special reactive groups and diverse structures can overcome the problems in the detection and removal of mercury ions.In different chemical structures,the thioacetal structure not only has the function of ROS responsiveness,but also has the coordination effect on mercury ions.Based on the structural and functional characteristics of thioacetal,the research content of this paper is mainly divided into the following three parts:(1)1,6-Hexanedithiol(or 3,6-dioxa-1,8-octandithiol),p-Anisaldehyde and m PEG2k-SH are directly reacted in one-pot method to obtain amphiphilic ABA polymer.Through the design of the polymer structure,two monomers with different hydrophobicity are used to synthesize the polymer to obtain micelles with different internal hydrophobicity.The degradation rate,morphological changes and drug release of the two micelles were studied.The change of polymer structure affects the release rate of the drug,and can achieve the effect of controlled release.In the study of the in vitro release behavior,cell internalization and in vitro anticancer effect of drug-loaded micelles on He La cells,it has been proved to have good anticancer effect.(2)1,6-Hexanedithiol,p-Anisaldehyde and m PEG2k-SH are directly reacted in one pot method to obtain amphiphilic ABA polymer.The degradation rate,morphological changes and drug release of micelles were studied.The reactive oxygen species(ROS)and acid(p H)dual response system has better drug release effects,and the dual response structure is more conducive to accurately positioning the tumor site to release drugs.The results show that the drug release amount and controlled release effect can be improved.(3)3,6-dioxa-1,8-octandithiol,1-Pyrenecarboxaldehyde and m PEG2k-SH are directly reacted in one pot method to obtain amphiphilic ABA polymer fluorescent probe.The optical response of the probe to Hg²⁺was tested under certain test conditions.The probe has a lower detection limit LOD=12 n M.In the subsequent various ion interference experiments,it also showed extremely high selectivity.It has excellent performance in the test of stability and response speed,and it has practical application value to be able to realize the rapid identification and real-time detection of Hg²⁺.In addition,when testing directly in water,the polymer fluorescent probe not only has the detection ability,but also has a strong ability to adsorb and remove Hg²⁺.