Preparations And Cytoactive Of Nanocarrier Based On Chitosan Derivatives With PH And ROS Responsive Property

The main research of this subject is based on the properties of chitosan,the use of phenylo boric acid in the reactive oxygen species(ROS)under the conditions of oxidative stress,bonding pH-sensitive quercetin,the construction of pH and ROS responsiveness system,the preparation of nanoparctice,containing drugs,the site of the site to achieve fixed release,for the treatment of some diseases,such as cancer,inflammation.In view of the cell microenvironment of reactive oxygen species,including basic,hydrogen peroxide(H2O2),singlet oxygen(1O2),superoxide anion(O2 ·)and hydroxyl radical(HO ·),the of concentration inflammatory tumor site will be significantly increased,will produce oxidative stress phenomenon,accompanied by decreased pH.Phenylo boric acid is sensitive to ROS,and the bound quercetin is reverse cleaved under acidic conditions to achieve pH response.Through the achievement of dual respond of pH and ROS,the drugs containing in nanospheres can achieve synergistic effect at the site of inflammation to provide better treatment for the disease.The value in the filed of medical treatment is more and more remarkable.It is sure to contribute to human health.This intelligent drug carrier prepared can improve the efficacy and reduce side effects.Quercetin can be used as an anti-inflammatory and antitumor agent.Taking into account the microenvironment of tumor cells:ROS and pH,this study mainly expounds the preparation and characterization of nanospheres,including the route of synthesis,molecular weight,particle size,Zeta potential,electron microscopy,elemental analysis and determining drug loading and the loading efficiency of nanospheres.The drug loading was 6.88%and the entrapment rate was 82.59%.The cumulative release curve of the drug in 72h verify the ability of the drug release,but also shows that the nanospheres have dual response of pH and ROS.When simulating pH5.8 inside cells under inflammatory conditions,the cumulative drug release reach peak value.Next,MTT cell experiment was done to valiable the inhibitory effect of drugs carried by nanoparctice on the tumor or inflammatory cells.A549,Hela,HepG2 were chosen,they both showed good IC50 results with low survival rate of tumor cells which means good effect.Based on the above considerations,the GCBQ nanospheres were designed with pH/ROS double response,targeting tumor cells,slow release drug release,improving the efficacy and reducing the side effects.