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With the development of polymer materials science, medicine and biology science class cross, the drug delivery system has been developed rapidly, emerging many polymer materials. In clinical applications, the need of a biodegradable polymer material, for this is the design and synthesis of a temperature sensitive polyethylene glycol - peptide amphiphilic block copolymer drug carrier material, and its performance studied. This selection of the raw material of polyethylene glycol having a biocompatible, immunology inert, non-toxic, and a molecular weight of 30,000 or less can be excreted; polypeptide is one of the essential nutrients, and can be degraded to the body's internal source substances, absorbed by the body and use this paper the synthesis of the target compound is also non-toxic, biocompatible, and the final product is formed hydrogel. New functional polymer hydrogel is a non-soluble in water, but can absorb large amounts of water swellable material, for three-dimensional network, or interpenetrating network structure, its main chain or branched chain contains a large number of hydrophilic groups, so as drugs The carrier material has become today one of the hotspots. In this paper, an amino acid as the raw material, respectively after protection of the amino group and a carboxyl group, using a liquid phase method to synthesize dipeptide, tripeptide, after removal of the Boc protection, carboxylic acid ester hydrolysis after amino HOBt / DIC condensation, a synthetic hexapeptide. Its structure was characterized using 1H-NMR. Then a terminal hydroxyl group of polyethylene glycol ethyl bromoacetate, hydrolysis of the two-step activation of the terminal carboxyl group, synthesis of different amino acid sequence, and hexapeptide HOBt / DIC condensation of polyethylene glycol - peptide amphiphilic block copolymer. The use of infrared spectroscopy (Ft. IR), nuclear magnetic resonance spectrum (1H-NMR), gel permeation chromatography (GPC) of its chemical structure and molecular weight distribution were characterized. Comparative analysis of the final product to the process of forming a gel after the 1H-NMR spectra that is due to hydrogen bonding, hydrophobic end extending inwardly, the hydrophilic end wrapped or dispersed in the surface of the hydrophobic end, forming a micelle, under heating conditions further to form the hydrogel; polyethylene glycol - peptide amphiphilic block copolymers temperature sensitivity measured from the test results, the mass ratio of 6% of the polymer solution into a gel temperature is 37 ℃, while in the 65 ℃ to dissolve, so that can be used as a pharmaceutical carrier material. Is designed and synthesized by the temperature sensitivity of the polyethylene glycol - peptide amphiphilic block copolymer, for the synthesis of a biodegradable drug carrier material to provide the basis for the study.
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