title: Ultrasensitive detection of superoxide anion released from living cells using a porous Pt-Pd decorated enzymatic sensor.
abstract: Considering the critical roles of superoxide anion (O2(∙-)) in pathological conditions, it is of great urgency to establish a reliable and durable approach for real-time determination of O2(∙-). In this study, we propose a porous Pt-Pd decorated superoxide dismutase (SOD) sensor for qualitative and quantitative detection O2(∙-). The developed biosensor exhibits a fast, selective and linear amperometric response upon O2(∙-) in the concentration scope of 16 to 1,536 μM (R(2)=0.9941), with a detection limit of 0.13 μM (S/N=3) and a low Michaelis-Menten constant of 1.37 μM which indicating a high enzymatic activity and affinity to O2(∙-). Inspiringly, the proposed sensor possesses an ultrahigh sensitivity of 1270 μA mM(-1)cm(-2). In addition, SOD/porous Pt-Pd sensor exhibits excellent anti-interference property, reproducibility and long-term storage stability. Beyond our expectation, the trace level of O2(∙-) released from living cells has also been successfully captured. These satisfactory results are mainly ascribed to (1) the porous interface with larger surface area and more active sites to provide a biocompatible environment for SOD (2) the specific biocatalysis of SOD towards O2(∙-) and (3) porous Pt-Pd nanomaterials fastening the electron transfer. The superior electrochemical performance makes SOD/porous Pt-Pd sensor a promising candidate for monitoring the dynamic changes of O2(∙-)in vivo.
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: Tingting
authors.initials: T
authors.lastname: Liu
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: Libo
authors.initials: L
authors.lastname: Shi
authors.affiliation: Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Li
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 / Q000379:methods*; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D057230:Limit of Detection; D016062:Porosity; D013482:Superoxide Dismutase / Q000378:metabolism*; D013481:Superoxides / Q000032:analysis* / Q000378:metabolism; D000099156:Superoxide Dismutase 2
chemical_list: D004800:Enzymes, Immobilized; D013482:Superoxide Dismutase; D013481:Superoxides; D000099156:Superoxide Dismutase 2
keywords: Living cells; O(2)(∙−) with trace level; Porous Pt–Pd; Superoxide anion detection; Superoxide dismutase; Ultrahigh sensitivity