Development Of A LDL-selective Adsorbens And Study The Biocompatibility Of The Material

Many researches have showed that both elevated level and oxidation of low-density lipoprotein (LDL) are associated with an increased incidence of atherosclerosis AS. On the other hand, high-density lipoprotein (HDL) can retard the progression of AS. Therefore, many researchers both domestic and abroad have studied the techniques that can decrease the level of LDL in the blood without a significant loss of HDL. Recently, LDL apheresis has been applied to clinic and achieved better effect.In this study, the principle of preparing the LDL-selective adsorbens is that the electronegative Heparin molecule can specifically bind to the electropositive LDL molecule through electrostatic interactions, and thus by means of solid-liquid phase and two-step synthetic technique the LDL-selective adsorbens is prepared by covalently immobilizing Heparin onto the surface of the carrier (PVA-1799) with the aid of bifunctional group linking agent.By analyzing the property of the LDL-selective adsorbens, the current research showed that Heparin can be successfully and covalently immobilized onto the surface of the carrier; and over 18μg ligang could be immobilized onto 1 g of PVA-1799 granules.The adsorbability of adsorbents was studied in vitro. Experimental results indicated that, under weak alkaline environment (PH7.4~9.5), the adsorbens had higher adsorptive efficiency for LDL but nearly no adsorption for HDL. After 2-4 hours'dynamic circulation, the adsorptive efficiency concerning LDL was about 60%, which suggested the adsorbens was more efficient .This study studied the biocompatibility of the LDL-selective adsorbens primarily, including its blood compatibility and cytotoxicity. Platelet adhesion test and blood clotting test suggested the adsorbens had few platelet adhesion and better anticoagulant property. By observing the hemolysis test, the adsorbens had good hema-compatibility. Utilizing the method of MTT, the result of cytotoxicity test suggested the adsorbens had no cytotoxicity. In a word, the adsorbens had good biocompatibility.