کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
869427 909830 2007 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Improved specificity of reagentless amperometric PQQ-sGDH glucose biosensors by using indirectly heated electrodes
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Improved specificity of reagentless amperometric PQQ-sGDH glucose biosensors by using indirectly heated electrodes
چکیده انگلیسی

Indirectly heated electrodes operating in a non-isothermal mode have been used as transducers for reagentless glucose biosensors. Pyrroloquinoline quinone-dependent soluble glucose dehydrogenase (PQQ-sGDH) was entrapped on the electrode surface within a redox hydrogel layer. Localized polymer film precipitation was invoked by electrochemically modulating the pH-value in the diffusion zone in front of the electrode. The resulting decrease in solubility of an anodic electrodeposition paint (EDP) functionalized with Osmium complexes leads to precipitation of the redox hydrogel concomitantly entrapping the enzyme. The resulting sensor architecture enables a fast electron transfer between enzyme and electrode surface. The glucose sensor was operated at pre-defined temperatures using a multiple current-pulse mode allowing reproducible indirect heating of the sensor. The sensor characteristics such as the apparent Michaelis constants KMapp and maximum currents Imaxapp were determined at different temperatures for the main substrate glucose as well as a potential interfering co-substrate maltose. The limit of detection increased with higher temperatures for both substrates (0.020 mM for glucose, and 0.023 mM for maltose at 48 °C). The substrate specificity of PQQ-sGDH is highly temperature dependent. Therefore, a mathematical model based on a multiple linear regression approach could be applied to discriminate between the current response for glucose and maltose. This allowed accurate determination of glucose in a concentration range of 0–0.1 mM in the presence of unknown maltose concentrations ranging from 0 to 0.04 mM.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biosensors and Bioelectronics - Volume 22, Issue 12, 15 June 2007, Pages 3014–3020
نویسندگان
, , , , , ,