Xiao Ting, Wang Shuang, Yan Mengxia, Huang Jianshe, Yang Xiurong
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China; University of Science and Technology of China, Hefei, 230026, China.
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
Talanta. 2021 Jan 1;221:121362. doi: 10.1016/j.talanta.2020.121362. Epub 2020 Jul 10.
Acetylcholinesterase (AChE) plays an essential role in biological signal transmission, the aberrant expression of which could cause diverse neurodegenerative diseases. Herein, based on the oxidase-like activity of manganese dioxide nanosheets (MnO NSs), we found that MnO NSs could directly oxidize thiamine into intensely fluorescent thiochrome without the need of peroxides. When AChE was introduced, acetylthiocholine could be hydrolyzed to generate thiocholine, which efficiently triggered the reduction of MnO NSs into Mn, resulting in the decrease of fluorescence. Owing to the inhibiting effect of tacrine to the AChE activity, the decomposition of MnO was hindered, thus leading to the fluorescence recovery. According to the above mechanism, we constructed a simple, low-cost, label-free, facile and rapid synthetic fluorescent biosensor for highly sensitive and selective detection of AChE activity and screening of its inhibitor. This biosensor obtained a good linear range from 0.02 to 1 mU/mL and an extremely low detection limit of 15 μU/mL for AChE assay, as well as a sensitive screening for tacrine and an excellent applicability in human serum samples. These results suggested that our proposed method would be potentially applied in monitoring the disease progression.
乙酰胆碱酯酶（AChE）在生物信号传导中起着至关重要的作用，其异常表达可导致多种神经退行性疾病。在此，基于二氧化锰纳米片（MnO NSs）的类氧化酶活性，我们发现MnO NSs可直接将硫胺氧化为强荧光硫色素，无需过氧化物。引入AChE后，乙酰硫代胆碱可水解生成硫代胆碱，硫代胆碱能有效触发MnO NSs还原为Mn，导致荧光减弱。由于他克林对AChE活性的抑制作用，MnO的分解受到阻碍，从而导致荧光恢复。基于上述机制，我们构建了一种简单、低成本、无标记、简便快速的合成荧光生物传感器，用于高灵敏、选择性地检测AChE活性及其抑制剂的筛选。该生物传感器对AChE检测的线性范围为0.02至1 mU/mL，检测限极低，为15 μU/mL，对他克林具有灵敏的筛选能力，在人血清样本中具有良好的适用性。这些结果表明，我们提出的方法可能用于监测疾病进展。
