The Basic Study Of Drug Coating Functional Endoscopic Instruments

Object With the rapid development of digestive endoscopy and innovative technologies,endoscopy has developed from a simple endoscopic diagnostic tool to a means of diagnosis and treatment of unity.Various endoscopic treatments such as endoscopic mucosal resection(EMR),endoscopic mucosal dissection(ESD),oral endoscopic myotomy(peroral endoscopic myotomy,POEM),by Endoscopic submucosal tunnel resection(STER),endoscopic retrograde cholangiopancreatography(endoscopic retrograde cholangiopancreatography,ERCP)have been emerging and maturing.Upper gastrointestinal bleeding is not only a common digestive disease,but also a common complication of the endoscopic treatment.Traditional medical treatment for upper gastrointestinal bleeding mainly include localized spraying,injecting or intravenous drop infusing of styptic medicine.Currently widely used styptic drug such as thrombin can locally effect on the surface of the lesion and soon form a stable blood clot.But thrombin sprayed to the targeted tissue is rapidly diluted by tissue fluid,which leads to the decreasing drug efficacy.With the continuous development of endoscopic instruments,a variety of anastomosis clips for stypsis and perforation closing begin to appear.As one of the important endoscopic instruments titanium clips only assume the role of physical therapy for local damage.Many scholars try to invent a medical metal substrate which can make sure sustain releasing thrombin.But all of the current study are based on the biologically inert material with poor biological activity and its ionic toxicity of heavy metal can cause the inefficacy of thrombin.The study presents the pattern which coats drugs on endoscopic device based on coating technology.It can improve the success rate of endoscopic hemostasis and provides technical support for the transform from simple "naked" endoscopic instruments to "functional" drug coating complex endoscopic instruments.Meterial and Method Drug coating complex 304 plates: Hydroxyapatite was bonded to the 304 plates which are as the same as the endoscopic instruments material by nooxide layer technique.After that thrombin was bonded to the complex material.So we completed the "thrombin-Hydroxyapatite-Nooxide layer-metal" composite system.ELISA: We measured the thrombin concentration under ideal environment by using human thrombin(thrombin)ELISA assay kit at different times in the physiological saline and used the multifunctional enzyme label to read the absorption..Statistical analysis: Data between two groups were analyzed by Student’s t test.A statistically significant difference was assumed at P≤0.05.The results1.At first thrombin released rapidly and the concentration reached its peak in 60 min.Then thrombin released very slowly but it could maintain a certain drug concentration.2.Thrombin coating complex plates can steady release the durg during different intervals.Conclusion(1)This study completed the "thrombin-Hydroxyapatite-Nooxide layer-metal" composite system by exploiting photoelectron spectroscopy(XPS)technology.(2)We detected the release of thrombin on the composite material by using human thrombin(thrombin)ELISA assay kit.(3)According to the experimental result,thrombin coating composite plates can release thrombin effectively and it can maintain certain drug concentration.It can not only eliminate the limitation of current endoscopic treatment,but also can reduce the incidence of delayed bleeding in endoscopic treatment.