Preparation And Properties Of Modified Natural Polymer/Polyacryloyl Hydrazide Hydrogels

Natural polymers carboxymethyl cellulose(CMC)and hyaluronic acid(HA)have excellent biocompatibility and biodegradability,but there also are some deficiencies exist,for example,the viscosity of carboxymethyl cellulose solution and the stability of hyaluronic acid,which limits its application.In this thesis,sodium periodate was used to partial open oxidation HA and CMC to preparation oxidation carboxymethyl cellulose(oxi-CMC)and oxidation hyaluronic acid(oxi-HA),and cross-linking with polyacryloyl hydrazide(PAH)to preparation modified natural polymer/polyacryloyl hydrazide hydrogels.The gelling time,internal morphology,rheology property,swelling ratio,degradation behavior and the in vitro release of model protein drug bovine serum albumin(BSA)was investigated.1.Polymethyl acrylate(PMA)was prepared from methyl acrylate,and PAH was prepared through ammonolysis reaction form PMA,the structure was characterized by1 H NMR,the molecular weight of PAH was characterized by gel permeation chromatography(GPC).Oxi-CMC was prepared from CMC and cross-linked with PAH via Schiff base reaction to prepare series of oxi-CMC/PAH hydrogels.The structure of oxi-CMC/PAH hydrogel was characterized by FT-IR,the swelling behavior,degradation behavior,rheology property at 37? and the micromorphology of freeze-dried oxi-CMC6/APH3 hydrogel was explored.Using BSA as a model protein drug,in vitro release of BSA from oxi-CMC6/PAH3 hydrogel was measured at 37?.The degradation percentage of oxi-CMC6/PAH3 hydrogel was about 47% after 20 days at 37? in phosphate buffered solution(PBS).The cumulative release percentage of BSA from drug-loaded oxi-CMC6/PAH3 hydrogel was about 79% in a week at 37? in PBS solution,the results showed that oxi-CMC/PAH hydrogels had good stability and controlled drug release ability in PBS solution.2.Oxi-HA was prepared from HA and cross-linked with PAH via Schiff base reaction to prepare series of oxi-HA/PAH hydrogels.The structure of oxi-HA/PAH hydrogel was characterized by FT-IR,the swelling ratio,degradation behavior,rheology property at 37? and the micromorphology of freeze-dried oxi-HA6/PAH3 hydrogel was investigated.Using BSA as a model protein drug,the in vitro release abilities of oxi-HA6/PAH3 hydrogel was measured at 37? in PBS solution.The degradation percentage of oxi-HA6/PAH3 hydrogel was about 66% after 20 days at 37? in PBS solution.The cumulative release percentage of BSA from drug-loaded oxi-HA6/PAH3 hydrogel was about 86% in 10 days at 37? in PBS solution,the results showed that oxi-HA/PAH hydrogel had good stability and controlled drug release ability in PBS solution.3.The oxi-HA solution mixed with oxi-CMC solution and cross-linked with PAH via Schiff base reaction to prepare series of oxi-HA/oxi-CMC/PAH hydrogels.The structure of oxi-HA/oxi-CMC/PAH hydrogel was characterized by FT-IR,the swelling ration,degradation behavior,rheology property at 37? were explored.The micromorphology of freeze-dried oxi-HA6/oxi-CMC6/PAH3 hydrogel was presented.Using BSA as a model protein drug,the in vitro release was used to evaluate the drug controlled release ability at 37?.The results showed that oxi-HA/oxi-CMC/PAH hydrogels had good stability and controlled drug release ability in PBS solution but poor mechanical properties.Comparing research results,the degradation rates of oxi-HA/PAH hydrogels were faster than them of oxi-CMC/PAH hydrogels and oxi-HA/oxi-CMC/PAH hydrogels,the yield stress values of oxi-CMC/PAH hydrogels were higher than them of other hydrogels,the drug conrolled release properties of oxi-HA/PAH hydrogels were better than them of other hydrogels.