TY - JOUR
T1 - Amperometric monitoring of lactate accumulation in rabbit ischemic myocardium
AU - Marzouk, Sayed A.M.
AU - Cosofret, Vasile V.
AU - Buck, Richard P.
AU - Yang, Hua
AU - Cascio, Wayne E.
AU - Hassanc, Saad S.M.
N1 - Funding Information:
S. Marzouk gratefully acknowledges Ain-Shams University, Cairo, Egypt for providing resources for his stay at University of North Carolina. Authors like to acknowledge R.B. Ash for the wafer fabrication and D. Sandiford for technical assistance. This work was supported, in part, by grants ROl HL48769 and PO1 HL27430 from the NIH, HLBI, Bethesda, MD.
PY - 1997/9
Y1 - 1997/9
N2 - Fabrication and characterization of miniature, flexible, planar biosensors for monitoring L-lactate accumulation in an ischemic myocardium are described. Three configurations of Au-based electrodes were fabricated by a photolithographic technique on flexible polyimide Kapton® foil. All sensors are based on an immobilized lactate oxidase with amperometric detection of the enzymatically produced hydrogen peroxide at a platinum-electroplated-gold base electrode polarized at 0.5 V versus Ag/AgCl. An inner electropolymeric layer is used to prevent electrode fouling and to reject the interference effects of easily oxidizable molecules. In addition, a diffusion controlling outer layer that greatly enhances the linear dynamic range of the sensor, is obtained by casting a polyurethane external film. The developed sensor was evaluated in vitro and proved to have high selectivity, good operational stability, good accuracy and precision (average recovery = 102.3 ± 0.4% for control sera), fast response time (t95 = 20 s) and high upper limit of the linear dynamic range (25-80 mM, with sensitivity of 1.7-0.4 nA mM-1, respectively at PO2 = 15 mmHg). Subsequently, the sensor was brought into direct contact with the surface of the rabbit papillary muscle and used for continuous quantitative monitoring of extracellular lactate accumulation during no-flow ischemia.
AB - Fabrication and characterization of miniature, flexible, planar biosensors for monitoring L-lactate accumulation in an ischemic myocardium are described. Three configurations of Au-based electrodes were fabricated by a photolithographic technique on flexible polyimide Kapton® foil. All sensors are based on an immobilized lactate oxidase with amperometric detection of the enzymatically produced hydrogen peroxide at a platinum-electroplated-gold base electrode polarized at 0.5 V versus Ag/AgCl. An inner electropolymeric layer is used to prevent electrode fouling and to reject the interference effects of easily oxidizable molecules. In addition, a diffusion controlling outer layer that greatly enhances the linear dynamic range of the sensor, is obtained by casting a polyurethane external film. The developed sensor was evaluated in vitro and proved to have high selectivity, good operational stability, good accuracy and precision (average recovery = 102.3 ± 0.4% for control sera), fast response time (t95 = 20 s) and high upper limit of the linear dynamic range (25-80 mM, with sensitivity of 1.7-0.4 nA mM-1, respectively at PO2 = 15 mmHg). Subsequently, the sensor was brought into direct contact with the surface of the rabbit papillary muscle and used for continuous quantitative monitoring of extracellular lactate accumulation during no-flow ischemia.
KW - Amperometric biosensors
KW - Ischemia
KW - Lactate monitoring
KW - Papillary muscle
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U2 - 10.1016/S0039-9140(96)02175-3
DO - 10.1016/S0039-9140(96)02175-3
M3 - Article
C2 - 18966893
AN - SCOPUS:0030791221
SN - 0039-9140
VL - 44
SP - 1527
EP - 1541
JO - Talanta
JF - Talanta
IS - 9
ER -