Rapid Detection of Irreversible Acetylcholineasterase Inhibitor by Mass Spectrometry Assay

Abstract

Here we developed a rapid method to detect acetylcholinesterase (AChE) activity by matrix‐assisted laser desorption/ionization Fourier transform mass spectrometry (MALDI‐FTMS) for screening irreversible AChE inhibitors. Due to its good salt‐tolerance and low sample consumption, MALDI‐FTMS could facilitate rapid detection, especially detection in real application. AChE activity was determined through calculating abundance of substrate and product in mass spectrometry. By this approach, we investigated the relation of organophosphorous (OP) concentrations and AChE inhibition. Shown in different inhibition curves from different OP pesticides, enzyme inhibitions still kept good correlation with concentration of OPs. Finally, this AChE‐inhibited method was applied to screen whole bloods of four decedents and discuss their death reason. In contrast to healthy persons, three of decedents showed low AChE activity, and probably died for irreversible AChE inhibitors. Through the following detecting in GC‐MS/MS, the possible death reason of these three decedents was confirmed, and another decedent actually died for sumicidin, a non‐AChE inhibitor. It demonstrated that screening irreversible AChE inhibitors by detecting enzyme activity in MALDI‐FTMS provided fast and accurate analysis results and excluded another toxicants not functioning on AChE. This method offered alternative choices for indicating the existence of enzyme inhibitors.

Dual Enzyme Activities Assay by Quantitative Electrospray Ionization Quadrupole-Time-of-Flight Mass Spectrometry

“…Finally, this method was applied to study GST and AChE activity in whole bloods of four deceased and five healthy people. The variation of enzyme activity was in agreement with information from gas chromatography (GC)-MS analysis 40 and confirmed that the developed method provided reliable results about enzyme activity rapidly and significantly. Thus, this method would give accurate information for responding to toxic compounds and offer an alternative choice for detecting enzyme activity.…”

Acetylcholinesterase liquid crystal biosensor for identification of AChE inhibitors by a reactivator

“…From the foregoing designed principle and the corresponding experimental phenomenon (Figure 2(ac)), it is observed that the relatively enhancing birefringent optical images is obtained after reactivation treatment with pralidoxime reactivator. Some researches have appointed that the efficacy of reactivation is dependent on the conjugated phosphonate structure [6,7]. This means that the OPs inhibited AChE with different conjugated phosphonate structure can be reactivated with different efficacy using a reactivator.…”