In situ 형성이 가능한 헤파린과 PEG계 생체 적합성 하이드로젤
In situ forming heparin and PEG based hydrogels for medical application
- 주제(키워드) Hydrogel coating
- 발행기관 아주대학교
- 지도교수 박기동
- 발행년도 2011
- 학위수여년월 2011. 2
- 학위명 석사
- 학과 및 전공 일반대학원 분자과학기술학과
- 실제URI http://www.dcollection.net/handler/ajou/000000011530
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
Surface modification of the biomaterials was widely investigated to improve bio compatibility. In particular, the PEG based hydrogel coating systems were developed due to various advantages of the hydrogels such as high hydrophilicity and lubricity. Heparin has been studied as a bio-active material for surface modification to produce not only bio compatible surface but also anti-coagulant surface. Heparin is the most commonly used anticoagulant reagent in clinical use and heparinization of surfaces which has been shown to be a successful strategy to prevent thrombus formation and to improve blood compatibility of blood-contacting medical devices. However, physical adsorption of hydrogels limits the durability in the long-term exposure in vivo. In this study, in situ forming heparin and PEG based hydrogels as a coating material was developed to improve blood compatibility of the metal devices and the durability of the hydrogel coating layer on the surface. 316L stainless steel (SS) substrates were simply and rapidly coated with hydrogels via horseradish peroxidase (HRP) enzymatic reaction in presence of hydrogen peroxide (H2O2). After hydrogel coating, durability of the hydrogel coating layer was evaluated. Heparin and PEG based hydrogel coating layer was stable for 7 days. Hydrogel coated surface effectively inhibited the protein adsorption and platelet adhesion. Surface bound heparin has suppressed the coagulation on the hydrogel coated surface by inactivating antithrombin. Our results demonstrated that the in situ forming heparin and PEG based hydrogel has great potential for use as a surface coating materials to improved blood compatibility of the metal surface.
more목차
I. INTRODUCTION 1
A.Biomaterial-body interaction at biointerface 1
B.Surface modifications for improved biocompatibility 4
1. Hydrogel 5
1) In situ forming hydrogel 6
2) Application of hydrogel 7
2. Heparin 9
1) Structure of heparin 9
2) Medical importance of heparin 12
3) Interaction of heparin with proteins 17
C. Hydrogel coating 21
D. Objectives 22
II. EXPERIMENTS 23
A. Materials 23
B. Synthesis of Tetronic-Tyramine/Dopamine (TTD) conjugates 24
C. Synthesis of NH2-PEG-Tyramine (NH2-PEG-TA) conjugates 26
D. Synthesis of HT and HPT conjugates 29
E. Preparation of heparin and PEG based hydrogel coated Surface 30
1. Mechanical property 30
2. Hydrogel coating 30
3. Coating stability test 31
F. Bloodcompatibility test 34
1. Factor Xa assay 34
2. Protein adsorption 35
3. Platelet adhesion 36
4. Hemolysis test 37
III. RESULTS AND DISCUSSION 38
A. Synthesis and characterizations 38
B. Mechanical strength 42
C. Hydrogel coating stability 44
D. Factor Xa Assay 46
E. In vitro blood compatibility test 48
IV. CONCLUSIONS 55
V. REFERENCES 56
Abstract (in Korean) 64
