A Highly Sensitive Hydrogen Peroxide Biosensor Based on Hemoglobin Immobilized on Cadmium Sulfide Quantum Dots/Chitosan Composite Modified Glassy Carbon Electrode. Issue 11 (2nd October 2014)

• Record Type: Journal Article
• Authors: Butwong, Nutthaya; Zhou, Lin; Moore, Eric; Srijaranai, Supalax; Luong, John H. T.; Glennon, Jeremy D.; Aggarwal, Suresh K.
• Is Part Of: Electroanalysis. Volume 26:Issue 11(2014:Nov.)
• Page Start: 2465
• Page End: 2473
• Publication Date: 2014-10-02
• Subjects: Electrochemical analysis -- Periodicals; Chemistry, Analytical -- Periodicals; Electrochemistry -- Periodicals; 543.4
• DOI: 10.1002/elan.201400353
• Languages: English
• ISSNs: 1040-0397

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>An <sc>L</sc>‐cysteine capped cadmium sulfide‐chitosan nanocomposite has been synthesized, characterized and used for surface modification of a glassy carbon electrode. With direct electron transfer, hemoglobin (Hb) adsorbed strongly on the nanocomposite and displayed excellent bioelectrocatalysis for H₂O₂. The biosensor was capable of reducing H₂O₂ at −0.35 V, with a detection limit of 3.13 nM, linearity in the range of 15 nM to 10 µM and a response time of less than 2 s. The MichaelisMenten constant (<italic>K</italic>_M) was 0.57 nM, attesting high bioelectrocatalysis of immobilized Hb for H₂O₂. Reproducibility of the fabrication method was very satisfactory with a relative standard deviation of 5.3 %. The biosensor lost only 6.5 % of its original response after 7 days when stored in a pH 7.4 PBS at 4 °C.</p> </abstract>