title: Immobilization of superoxide dismutase on Pt-Pd/MWCNTs hybrid modified electrode surface for superoxide anion detection.
abstract: Monitoring of reactive oxygen species like superoxide anion (O2(∙-)) turns to be of increasing significance considering their potential damages to organism. In the present work, we fabricated a novel O2(∙-) electrochemical sensor through immobilizing superoxide dismutase (SOD) onto a Pt-Pd/MWCNTs hybrid modified electrode surface. The Pt-Pd/MWCNTs hybrid was synthesized via a facile one-step alcohol-reduction process, and well characterized by transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction. The immobilization of SOD was accomplished using a simple drop-casting method, and the performance of the assembled enzyme-based sensor for O2(∙-) detection was systematically investigated by several electrochemcial techniques. Thanks to the specific biocatalysis of SOD towards O2(∙-) and the Pt-Pd/MWCNTs - promoted fast electron transfer at the fabricated interface, the developed biosensor exhibits a fast, selective and linear amperometric response upon O2(∙-) in the concentration scope of 40-1550 μM (R(2)=0.9941), with a sensitivity of 0.601 mA cm(-2) mM(-1) and a detection limit of 0.71 μM (S/N=3). In addition, the favorable biocompatibility of this electrode interface endows the prepared biosensor with excellent long-term stability (a sensitivity loss of only 3% over a period of 30 days). It is promising that the proposed sensor will be utilized as an effective tool to quantitatively monitor the dynamic changes of O2(∙-) in biological systems.
authors.affiliation: Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Xiangheng
authors.initials: X
authors.lastname: Niu
authors.affiliation: Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237, PR China. Electronic address: honglizhao@ecust.edu.cn.
authors.forename: Hongli
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Tang
authors.affiliation: Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237, PR China; State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, PR China. Electronic address: minbolan@ecust.edu.cn.
authors.forename: Minbo
authors.initials: M
authors.lastname: Lan
mesh_terms: D015374:Biosensing Techniques; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry*; D006801:Humans; D037742:Nanotubes, Carbon / Q000737:chemistry; D056951:Photoelectron Spectroscopy; D017382:Reactive Oxygen Species / Q000737:chemistry / Q000302:isolation & purification; D013482:Superoxide Dismutase / Q000737:chemistry*; D013481:Superoxides / Q000737:chemistry / Q000302:isolation & purification*; D014961:X-Ray Diffraction
chemical_list: D004800:Enzymes, Immobilized; D037742:Nanotubes, Carbon; D017382:Reactive Oxygen Species; D013481:Superoxides; D013482:Superoxide Dismutase
keywords: Enzyme-based electrochemcial sensor; High sensitivity and stability; Pt–Pd/MWCNTs hybrid; Superoxide anion detection; Superoxide dismutase