Dual Monitoring of Blood Acetylcholinesterase Content and Catalytic Activity Utilizing Fluorometry-Integrated Surface Plasmon Resonance.

Acetylcholinesterase inhibitors (AChEIs), particularly donepezil, are commonly used to treat mild-to-moderate Alzheimer's disease (AD). However, drug accumulation during long-term use could change AChE activity and content, leading to peripheral side effects and prompting medication discontinuation. However, there are a lack of methods to simultaneously determine the content and catalytic activity of AChE. By using phosphatidylinositol-specific phospholipase C to strip AChE from erythrocyte surfaces, we developed a novel method combining surface plasmon resonance and fluorescence detection for the simultaneous detection of AChE content and activity, producing stable, reliable, and accurate results. The established determination range spans from 263.37 ng/mL to 3000 ng/mL (4.05 nM to 46.15 nM) for concentration, and from 39.02 mU/mL to 1000 mU/mL for activity. Compared to traditional methods, this approach simplifies operations, reduces detection time, expands the dynamic range, and lowers detection limits, potentially advancing AChE-related research and supporting clinical diagnostics and drug development.