The Study Of Hydroxyethyl Starch 200/0.5 Synthesis

Hydroxyethyl starch 200/0.5 is a kind of middle molecular weight artificial plasma substitutes,which can be used for treatment of hemorrhage or shock caused by massive bleeding. In order to preparation out hydroxyethyl starch 200/0.5, determine the best preparation craft and process craft, this article conduct the research.The mainly results are as follows:1 By the use of the orthogonal design which choosing different level combination as influencing factors optimizing the synthetic route of hydrolysis reaction after epoxidation reaction and epoxidation reaction after hydrolysis reaction, then determine the best preparation process differently. This article draws the conclusion that the route of cornstarch’s epoxidation after hydrolysis reaction is better than cornstarch’s hydrolysis after epoxidation reaction by the compare of the time of preparation、the cost of preparation、the rate of production:cornstarch 20g、the time of hydrolysis reaction 3h、the temperature of hydrolysis reaction 60℃、the concentration of seriflux 28%、the concentration of hydrochloric acid 2mol/l、the time of epoxidation 3.5h、the dose of ethylene oxide 5.7ml、the concentration of sodium hydroxide0.8mol/l、the temperature of epoxidation 38℃、the rate of production41%.2 This article conducts the research and optimizion of hydroxyethyl starch 200/0.5’s processing procedure which include the decoloration of active carbon、the filtration of titanium rod、dialysis and iyophilization and then obtains the best the condition of procession:the temperature of active carbon decoloration 80℃、the dose of active carbon is cornstarch’s 1.5%、the time of active carbon decoloration 90min; the temperature of titanium rod’s filtration 80℃;the modle of dialysis bag 3500D、the temperature of dialysis 70℃the time of dialysis 4.5h; the concetration of iyophilization 12%、the thickness of iyophilization 9mm、the time of prefozen 2h、the time of iyophilization 24h.3 Using the various of instruments and methods determine the quality of hydroxyethyl starch 200/0.5.(1) By the use of infraed scanning, the infrared spectrum includes absorption peak at 856 cm-1.(2) Using the method which provided by health standards for drugs determines hydroxyethyl starch 200/0.5’s substitution degree. The range of standard MS is between 0.45 and 0.55.(3) Using the GPC-RI-MALLS determines the Mw and the Mw/Mn.The range of standard Mw is between 180000～230000. The range of standard Mw/Mn is below 4.5.(4) Using the spectropolarineter determines the than spin photometric. The range of standard than spin photometric is between+178°and +192°(5) Using the Gas chromatography determines the content of Ethylene glycol. The range of standard content of Ethylene glycol is below 60μg/g.(6) Using the Ubbelohde viscometer determines the hydroxyethyl starch 200/0.5’s viscosity. The range of standard viscosity is between 15.0 and 19.0.