title: Biomimetic hydrogels for biosensor implant biocompatibility: electrochemical characterization using micro-disc electrode arrays (MDEAs).
abstract: Our interest is in the development of engineered microdevices for continuous remote monitoring of intramuscular lactate, glucose, pH and temperature during post-traumatic hemorrhaging. Two important design considerations in the development of such devices for in vivo diagnostics are discussed; the utility of micro-disc electrode arrays (MDEAs) for electrochemical biosensing and the application of biomimetic, bioactive poly(HEMA)-based hydrogel composites for implant biocompatibility. A poly(HEMA)-based hydrogel membrane containing polyethylene glycol (PEG) was UV cross-linked with tetraethyleneglycol diacrylate following application to MDEAs (50 mum discs) and to 250 mum diameter gold electrodes within 8-well culture ware. Cyclic voltammetry (CV) of the MDEAs revealed a reduction in the apparent diffusion coefficient of ferrocenemonocarboxylic acid (FcCO(2)H), from 6.68 x 10(-5) to 6.74 x 10(-6) cm(2)/s for the uncoated and 6 mum thick hydrogel coated devices, respectively. Single frequency (4 kHz) temporal impedance measurements of the hydrogels in the 8-well culture ware showed a reversible 5% change in the absolute impedance of the hydrogels when exposed to a pH change between 6.1 to 7.2 and a 20% drop between pH 6.1 and 8.8.
authors.affiliation: Center for Bioelectronics, Biosensors and Biochips (C3B), Clemson University Advanced Materials Center, 100 Technology Drive, Anderson, SC 29625, USA. gusphyl@clemson.edu
authors.forename: Gusphyl
authors.initials: G
authors.lastname: Justin
authors.forename: Stephen
authors.initials: S
authors.lastname: Finley
authors.forename: Abdur Rub
authors.initials: AR
authors.lastname: Abdur Rahman
authors.forename: Anthony
authors.initials: A
authors.lastname: Guiseppi-Elie
mesh_terms: D000818:Animals; D040761:Biomimetic Materials; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D001831:Body Temperature; D005947:Glucose / Q000032:analysis / Q000378:metabolism; D006470:Hemorrhage / Q000378:metabolism; D006801:Humans; D020100:Hydrogels; D019344:Lactic Acid / Q000032:analysis / Q000378:metabolism; D008839:Microelectrodes; D055616:Microtechnology; D011092:Polyethylene Glycols; D011102:Polyhydroxyethyl Methacrylate; D019736:Prostheses and Implants
chemical_list: D020100:Hydrogels; D011102:Polyhydroxyethyl Methacrylate; D019344:Lactic Acid; D011092:Polyethylene Glycols; D005947:Glucose