Hemostatic Activity Of Pollock Skin Gelatin And Gelatin-based Composite Hemostatic Powder

Cod fish is an important kind of marine products,which is rich in resources and widely spread. It is one of the world’s largest annul catches,an important food which has big value.With the development of China’s aquatic products processing industry, the utilization of fish processing waste like fish skin has become a hot topic.This thesis took cod skin as raw materials to extract water-soluble gelatin.The extraction temperature was 65℃.We identified the gelatin and studied its physical and chemical properties.One kind of composite hemostatic powder was developed based on the relationship between molecular weight and hemostasis.Then, the hemostatic activity and hemostatic mechanismof it was studied.1.The experimental results of hydroxyproline show the extraction yield of gelatin is 39.87%.The UV-Vis spectra shows that the gelatin is quiet pure.The viscosity of the gelatin sample decreased with increasing temperature. Gel strength of the sample is lower than mammalian sources gelatin.Metal ion content test showed that calcium content of cod gelatin was significantly higher than that of mammals and eel, silver carp and other aquatic fish and it is one of the advantage of cod fish gelatin as materials to make hemostatic powder.2.Results of SDS-PAGE electrophoresis shows that the range of molecular weight of cod skin gelatin is widely spread.To separate different molecular weight of gelatin, we use 100KDa and 50KDa ultrafiltration membrane to separate the samples and get high,middle and low three different molecular weight samples.Experience of rat tail bleeding model,femoral artery cutting model and liver cutting model prove that effect on hemostatic of high molecular weight gelatin is the best.This result is an important basis on gelatin hemostatic material development.3.Took high molecular weight gelatin as main material,choose chitosan,sodium carboxymethyl cellulose and sodium alginate to mix the two substances in accordance with a certain proportion.The composite hemostatic powder is developed.Chosen three kind of composite hemostatic powder to do deeper research(gelatin:chitosan is 10:4,gelatin:carboxymethyl chitosan is 10:8 and gelatin:sodium alginate is 10:4)based on water absorbency.Experimental results show that the hemolytic rate of hemostatic powder is under the standard of biomedical materials.In vitro results showed that the composite hemostatic powder has procoagulant effect.Further animal experiments show that the composition the gelatin and three marine polysaccharides can improve hemostatic effect and the gelatin-chitosan powder is the best.4.By measuring the APTT.PT and TT to determine the effect of gelatin and gelatin hemostatic powder on endogenous coagulation system, the extrinsic coagulation system and common coagulation pathway.lt shows that gelatin can shorten APTT to affect endogenous coagulation system and shorten the clotting time. Platelet aggregation experiments showed gelatin can promote platelet aggregation,gelatin-chitosan powder and gelatin-carboxymethyl chitosan powder could strengthen platelet aggregation.Gelatin-chitosan powder has the strongest promotion power. Gelatin can promote the release of three active factor(PF4,P-selection and TXB2).The composition of gelatin and ocean-polysaccharides can strengthen the promotion. The effect on endogenous coagulation system, platelet aggregation and release of platelet activating factor is the main reason of the rapid hemostasis.