Photo-crosslinked copolymers of 2-hydroxyethyl methacrylate, poly(ethylene glycol) tetra-acrylate and ethylene dimethacrylate for improving biocompatibility of biosensors.
A copolymer containing 88% 2-hydroxyethyl methacrylate (HEMA), 9% poly(ethylene glycol) (MW 18.5 kDa) tetra-acrylate and 3% ethylene dimethacrylate was prepared and evaluated for use as a biocompatible interface between glucose biosensors and tissue in the rat. The glucose sensor utilizes glucose oxidase that is electrically 'wired' to a gold current collector by a reduction-oxidation polymer. Coatings of the copolymer were crosslinked in situ on the sensors using long wavelength ultraviolet light and 2,2-dimethoxy-2-phenyl-acetophenone as the initiator. The effect these films had on the current response to glucose was measured. Over a glucose concentration range of 0-30 mM, the average percentage decrease in response was 45 +/- 28% (mean +/- 95% confidence interval) at 37 degrees C for films that were about 0.1 mm thick, an acceptable value. Copolymer-treated and control electrodes were implanted in the intrascapular subcutaneous tissue of male Sprague-Dawley rats for three days. The explanted samples were evaluated using scanning electron microscopy. The control electrodes were highly encapsulated with fibrous material, while the copolymer-treated electrodes induced much less encapsulation. The results show this copolymer to be a candidate as a biocompatible coating for electrically wired oxidoreductase-based subcutaneous biosensors.
Quinn
C P
CP
Department of Chemical Engineering, University of Texas at Austin 78712-1062, USA.
Pathak
C P
CP
Heller
A
A
Hubbell
J A
JA
D000179:Acrylates / Q000138:chemical synthesis / Q000737:chemistry; D000818:Animals; D001672:Biocompatible Materials / Q000138:chemical synthesis*; D015374:Biosensing Techniques; D002138:Calibration; D003432:Cross-Linking Reagents / Q000737:chemistry; D005947:Glucose / Q000032:analysis; D008297:Male; D008689:Methacrylates / Q000737:chemistry*; D010777:Photochemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D014466:Ultraviolet Rays
D000179:Acrylates; D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D008689:Methacrylates; D011108:Polymers; D011092:Polyethylene Glycols; C005044:hydroxyethyl methacrylate; C004919:ethylene dimethacrylate; D005947:Glucose