Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237, PR China.
Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237, PR China.
Biosens Bioelectron. 2016 May 15;79:449-56. doi: 10.1016/j.bios.2015.12.061. Epub 2015 Dec 25.
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.
考虑到超氧阴离子 (O2(∙-)) 在病理条件下的关键作用，建立一种可靠和持久的方法来实时测定 O2(∙-) 非常紧迫。在本研究中，我们提出了一种多孔 Pt-Pd 修饰的超氧化物歧化酶 (SOD) 传感器，用于定性和定量检测 O2(∙-)。所开发的生物传感器在 16 至 1,536 μM 的 O2(∙-)浓度范围内表现出快速、选择性和线性的电流响应（R(2)=0.9941），检测限为 0.13 μM（S/N=3），米氏常数低至 1.37 μM，表明具有高酶活性和对 O2(∙-)的高亲和力。令人鼓舞的是，所提出的传感器具有超高的灵敏度，为 1270 μA mM(-1)cm(-2)。此外，SOD/多孔 Pt-Pd 传感器具有出色的抗干扰性、重现性和长期储存稳定性。出乎意料的是，还成功捕获了来自活细胞释放的痕量 O2(∙-)。这些令人满意的结果主要归因于 (1) 具有更大表面积和更多活性位点的多孔界面，为 SOD 提供了生物相容性环境；(2) SOD 对 O2(∙-)的特异性生物催化；(3) 多孔 Pt-Pd 纳米材料加快了电子转移。卓越的电化学性能使 SOD/多孔 Pt-Pd 传感器成为监测体内 O2(∙-)动态变化的有前途的候选者。
