کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
870226 | 909856 | 2007 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Oxygen tolerance of an implantable polymer/enzyme composite glutamate biosensor displaying polycation-enhanced substrate sensitivity Oxygen tolerance of an implantable polymer/enzyme composite glutamate biosensor displaying polycation-enhanced substrate sensitivity](/preview/png/870226.png)
Biosensors were fabricated at neutral pH by sequentially depositing the polycation polyethyleneimine (PEI), the stereoselective enzyme l-glutamate oxidase (GluOx) and the permselective barrier poly-ortho-phenylenediamine (PPD) onto 125-μm diameter Pt wire electrodes (Pt/PEI/GluOx/PPD). These devices were calibrated amperometrically at 0.7 V versus SCE to determine the Michaelis–Menten parameters for enzyme substrate, l-glutamate (Glu) and co-substrate, dioxygen. The presence of PEI produced a 10-fold enhancement in the detection limit for Glu (∼20 nM) compared with the corresponding PEI-free configurations (Pt/GluOx/PPD), without undermining their fast response time (∼2 s). Most remarkable was the finding that, although some designs of PEI-containing biosensors showed a 10-fold increase in linear region sensitivity to Glu, their oxygen dependence remained low.
Journal: Biosensors and Bioelectronics - Volume 22, Issue 7, 15 February 2007, Pages 1466–1473