首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Bio-smart materials: kinetics of immobilized enzymes in p(HEMA)/p(pyrrole) hydrogels in amperometric biosensors
Authors:Sean Brahim  Dyer Narinesingh  Anthony Guiseppi-Elie
Institution:1. Department of Chemical Engineering and Center for Bioelectronics, Biosensors and Biochips (C3B), Virginia Commonwealth University, Richmond, Virginia 23298;2. Department of Chemistry, The University of the West Indies, St. Augustine, Republic of Trinidad & Tobago;3. Department of Chemical Engineering and Center for Bioelectronics, Biosensors and Biochips (C3B), Virginia Commonwealth University, Richmond, Virginia 23298

ABTECH Scientific, Inc., Biotechnology Research Park, Richmond, Virginia 23219

Abstract:Various strategies are being pursued to confer the highly specific molecular recognition properties of bioactive molecules to the transducer action of inherently conductive polymers. We have successfully integrated inherently conductive polypyrrole within electrode-supported, UV cross-linked hydroxyethyl methacrylate (HEMA)-based hydrogels. These electroactive composites were used as matrixes for the physical immobilization of several oxidase enzymes to fabricate clinically important biosensors. Measurements were made of the amperometric responses via H2O2 oxidation for each biosensor. Apparent Michaelis constants, Km(app), for glucose oxidase immobilized in p(HEMA) membranes and in p(HEMA)/p(Pyrrole) composite membranes were 13.8 and 43.7 mM respectively compared to 33 mM in solution. The inclusion of polypyrrole in the hydrogel network increased the thermal stability of the immobilized enzyme at 60°C by 30% and 40% compared to p(HEMA) membranes and solution phase respectively. The composite also yielded larger Imax values (19 μA/cm?2) for glucose biosensors compared to similar glucose biosensors fabricated without the conducting polymer (15 μA). Km(app) values for cholesterol oxidase immobilized in the same composite films were ca. three orders of magnitude higher than the Km for the soluble enzyme. The polypyrrole component is shown to reduce diffusive transport but to confer thermal stability to these biosensors.
Keywords:
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号