Employing Modified Dextran And Protein As Functional

Based on the interaction between biomaterials and saccharide, protein as well as polynucleotides design of natural polymers promote the development of intelligent ,fine, and enviroment friendshiply biomaterials. The materials of dextran are used in many fields widely, such as biologic technique and biologic pharmacy, because it has the better biologic consistency, innocuity and degradation in fixed-point by enzyme. The materials of dextran could be made loading drug's nanoparticle which controlled the drug's release in biologic pharmacy and detached material in biologic technique. The material of enzymic protein was paid much attention, because it had high activated catalyse and specific selectivity.The biologic detached material and loading drug's nanoparticle were made of starch, chitosan and DEAE-Dextran; the concentration of peracetic acid indoor was determined by high activated catalyse of enzymy and enzymy-like protein. Some reactions availed on the chemical modifications of chitosan, such as deacylation, degradation with Y radiation, catalytic reaction, grafting reaction and cross linking reaction are used. The main content and conclusion in present paper were showed as follow:1.Starch was esterified with MAh in different reacting condition: Starch reacted with MAh in DMSO, not adding to catalyst; Starch reacted with MAh in DMF, not adding to catalyst; Starch reacted with MAh in DMF, adding to pyridine and changing to the time and temperature. MAh grafted to starch was approved by scanning the offspring which was made in the mentioned above three methods in FITR; Comparing to the substitutive ratio of MAh in the starch, the substitutive ratio of MAh was 5% approximately when the catalyst was not added in the reaction and 12% probably if the reaction was added the catalyst.2. The radiant dose was more ,and the deacetylation ratio of chitin which was radiated in γ-ray was more, and the radiant dose was 40Gy, 60Gy, 80Gy. The viscosity average molecular weight and deacetylation ratio of chitosan was 2.71×10~5 in viscosimetry and 77.26%; the which of chitosan which was radiated in Y -ray was 1.78×10~5, 1.07×10~5, 1.00×10~5 and 82.53%, 88.36%, 90.07%. A series of...