title: Sensitive electrochemical detection of hydroxyl radical with biobarcode amplification.
abstract: By using biobarcode nanoparticles, we have successfully constructed a DNA-based biosensor for amplified electrochemical detection of hydroxyl radical (·OH). Thiolated DNA1 (SH-DNA1) was firstly immobilized on the planar gold (Au) electrode. ·OH generated from Fenton reaction could induce serious oxidative damage of the DNA layer adsorbed on the electrode surface, which was monitored by an intercalating probe, methylene blue (MB). In order to enhance the sensitivity of the biosensor, DNA2-functionalized Au nanoparticles (DNA2-AuNPs) were used to amplify the response signal. The developed DNA-based biosensor could detect ·OH quantitatively with wide linear range up to 10mM and low detection limit of 3 μM, and exhibited satisfactory selectivity. On the other hand, this electrochemical biosensor could have potential application in the evaluation of antioxidant capacity.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, PR China.
authors.forename: Liang
authors.initials: L
authors.lastname: Wu
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.forename: Hejing
authors.initials: H
authors.lastname: Zhang
authors.forename: Gangbing
authors.initials: G
authors.lastname: Zhu
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Zhang
authors.forename: Jinhua
authors.initials: J
authors.lastname: Chen
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D055664:Electrochemical Techniques; D017665:Hydroxyl Radical / Q000032:analysis*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D013997:Time Factors
chemical_list: D017665:Hydroxyl Radical