Chapter Eight
Polymer-Based Biocompatible Surface
Coatings
Kai Yu, Guangzheng Gao and Jayachandran N. Kizhakkedathu
Centre for Blood Research, Department of Pathology and Laboratory Medicine,
University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
E-mail: jay@pathology.ubc.ca
8.1 INTRODUCTION
The performance of a material intended for biomedical applications depends on its
interfacial properties and reactions that occur when come in contact with biological
fluids. Non-specific protein adsorption at the biomaterial interface is the first
and critical event that initializes a cascade of host responses, including platelet
activation, blood coagulation, and complement activation.
1,2
Many approaches
have been used to prevent such non-specific interactions.
36
Coating or immobilization of surfaces with biomacromolecules such as
albumin
712
and anticoagulants like heparin
1318
have been widely studied to-
wards this purpose. Another approach to overcome this problem is to coat the
surface with synthetic hydrophilic polymers
4,19
and this method has been used
as a anti-fouling treatment for a number of applications including biosensors
20
and drug delivery systems.
21
It was demonstrated that such coatings frequently
extend the life span of biomedical devices
2223
and the circulation half life of drug
delivery systems.
2425
Several factors that affect the protein-repelling properties of polymer thin films
on surface include the similarity of interfacial free energies of the polymer with
that of water, interaction of proteins with polymers through hydrophobic or charge
interactions and environmental factors such as temperature and pH.
2628
In the
case of neutral hydrophilic polymer grafted surfaces, the steric barrier due to
high conformational entropy of anchored chains is one of the contributing factor
towards protein repulsion.
2935
Other factors include, the structure of the polymer
Biomaterials for MEMS, Edited b y M. Chiao and J.-C. Chiao
Copyright © 2011 by Pan Stanford Publishing Pte. Ltd.
www.panstanford.com
978-981-4241-46-5
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