Functional Design of Electrochemical Biosensors Using Polypyrrole
| Autor: | D.M.G. Preethichandra, Mitsuyoshi Onoda |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
010302 applied physics
Materials science Immobilized enzyme biology Computer Networks and Communications Applied Mathematics General Physics and Astronomy 02 engineering and technology 021001 nanoscience & nanotechnology Polypyrrole 01 natural sciences Amperometry Matrix (chemical analysis) chemistry.chemical_compound Adsorption chemistry Linear range 0103 physical sciences Signal Processing biology.protein Glucose oxidase Electrical and Electronic Engineering 0210 nano-technology Biosensor Nuclear chemistry |
| Zdroj: | IEEJ Transactions on Electronics, Information and Systems. 135:174-180 |
| ISSN: | 1348-8155 0385-4221 |
| DOI: | 10.1541/ieejeiss.135.174 |
| Popis: | In order to improve biosensor performance, namely, the sensitivity, response time, and linear range values, novel amperometric polypyrrole PPy glucose biosensors, achieved by three different immobilizing techniques, namely, physical adsorption, coentrapment, and a two-step method of coentrapment with superimposed physical adsorption, have been studied. Different enzyme loading and material properties resulted in varied immobilizing techniques, leading to dissimilarities in characteristics. In this study, Pt coated AnodiscsTM with 0.2 µm maximum pore size were used as electrodes to polymerize PPy at 0.3 mAcm-2 using a solution containing 0.05 mol/L pyrrole and 0.1 M NaPF6. The polymerization time was optimized to 90 s. In the coentrapment method, glucose oxidase GOx 1 mg/mL was added to the monomer solution while an aliquot of GOx 5 µL was placed on the prepolymerized electrode for physical adsorption. A combination of these two techniques was used as the last immobilization technique. The physical adsorption method gave a sensitivity of 3 mAcm-2 mol/L-1 and a linear range of 0.5 × 10-3 mol/L to 13 × 10-3 mol/L with a response time of 3 s. The sensitivity in the case of coentrapment was 3.75 mAcm-2 mol/L-1, while the value was 4.45 mAcm-2 mol/L-1 in two-step immobilization, thus giving 25% and 48% increases, respectively. The response times of 9 s and 8 s in the latter cases reveal possible repercussion taking place in enzyme immobilization in a three-dimensional 3D PPy matrix and a delay in the time required for glucose to reach the enzyme. The linear range of the two-step method was extended to 16 × 10-3 mol/L by reinforced enzyme loading. |
| Databáze: | OpenAIRE |
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