School of Materials Science and Engineering, University of Jinan, Jinan, 250022, China.
Mikrochim Acta. 2021 Apr 10;188(5):162. doi: 10.1007/s00604-021-04817-x.
A convenient and sensitive colorimetric assay for acetylcholinesterase (AChE) and its inhibitor has been designed based on the oxidase-like activity of {100}-faceted Pd square nanoplates which are grown in situ on reduced graphene oxide (PdSP@rGO). PdSP@rGO can effectively catalyze the oxidation of colorless 3,3',5,5'-tetramethylbenzidine (TMB) without the assistance of HO to generate blue oxidized TMB (oxTMB) with a characteristic absorption peak at 652 nm. In the presence of AChE, acetylthiocholine (ATCh), a typical AChE substrate, is hydrolyzed to thiocholine (TCh). The generated TCh can effectively inhibit the PdSP@rGO-triggered chromogenic reaction of TMB via cheating with Pd, resulting in color fading and decrease in absorbance. Thus, a sensitive probe for AChE activity is constructed with a working range of 0.25-5 mU mL and a limit of detection (LOD) of 0.0625 mU mL. Furthermore, because of the inhibition effect of tacrine on AChE, tacrine is also detected through the colorimetric AChE assay system within the concentrations range 0.025-0.4 μM with a LOD of 0.00229 μM. Hence, a rapid and facile colorimetric procedure to sensitively detect AChE and its inhibitor can be anticipated through modulating the oxidase-like activity of PdSP@rGO. Colorimetric method for detection of AChE and its inhibitor is established by modulating the oxidase mimetic activity of {100}-faceted Pd square nanoplates on reduced graphene oxide (PdSP@rGO).
基于原位生长在还原氧化石墨烯（PdSP@rGO）上的 100 面 Pd 方纳米片的类氧化酶活性，设计了一种用于乙酰胆碱酯酶（AChE）及其抑制剂的简便灵敏的比色测定法。PdSP@rGO 可以有效地催化无色 3,3',5,5'-四甲基联苯胺（TMB）的氧化，而无需 HO 的协助，生成具有 652nm 特征吸收峰的蓝色氧化 TMB（oxTMB）。在 AChE 的存在下，乙酰硫代胆碱（ATCh），一种典型的 AChE 底物，被水解为硫代胆碱（TCh）。生成的 TCh 可以通过与 Pd 的欺骗作用有效地抑制 PdSP@rGO 引发的 TMB 显色反应，导致颜色褪色和吸光度降低。因此，构建了一种用于 AChE 活性的灵敏探针，其工作范围为 0.25-5mUmL，检测限（LOD）为 0.0625mUmL。此外，由于他克林对 AChE 的抑制作用，也可以通过比色 AChE 测定系统在 0.025-0.4μM 的浓度范围内检测他克林，LOD 为 0.00229μM。因此，可以通过调节 PdSP@rGO 的类氧化酶活性来预期一种快速简便的比色法来灵敏检测 AChE 及其抑制剂。通过调节还原氧化石墨烯上的 100 面 Pd 方纳米片的氧化模拟活性，建立了用于检测 AChE 和其抑制剂的比色法。
