| Autor: |
Tasviri, Mahboubeh, Ghourchian, Hedayatollah, Gholami, Mohammad R., Rafiee-Pour, Hossain-Ali |
| Zdroj: |
Progress in Reaction Kinetics and Mechanism; May 2012, Vol. 37 Issue: 2 p161-172, 12p |
| Abstrakt: |
Horseradish peroxidase (HRP) was successfully immobilized on amine functionalized TiO2-coated multiwalled carbon nanotubes (NH2TiO2CNTs) by a convenient and efficient method. Electrochemical impedance spectroscopy, cyclic voltammetry and amperometry were applied to characterize the HRP/NH2- TiO2- CNT nano-composite. These techniques showed that the NH2TiO2CNTs greatly enhance the electron transfer between HRP and the modified electrode. Owing to the redox reaction of the electroactive centre of HRP, the HRP/NH2-TiO2-CNTs modified electrode exhibited a pair of quasi-reversible peaks with a peak-to-peak separation (Δ Ep)of 70.6 m V and a formal potential (E°’) of - 367.65 m V (versusAg/AgCl) in phosphate buffer solution. The charge transfer coefficient (a) and the apparent charge transfer rate constant (ks)were found to be 0.34 and 2.08 s-1 respectively. The prepared biosensor responded to H2O2with a linear range, detection limit, sensitivity and response time of 1.0 × 10−9to 1.0 × 10 −7M, 0.786nM, 28.4 μA A nM−1and 3 s, respectively. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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