Dual-mode fluorescence and colorimetric determination of acetylcholinesterase accomplished by BSA-MnO2 QDs with oxidase-mimetic activity

Abstract

It has been demonstrated that acetylcholinesterase (AChE) contributed significantly to the maintenance of normal cholinergic neurophysiology, and its abnormal expression has been linked to several diseases. Due to intrinsic self-confirmation and self-adjustment, multi-mode detection was able to provide more dependable and accurate results when compared to commonly used single-signal detection. Despite this, the problem of achieving multi-mode analysis of AChE has not been solved. In this study, we developed a dual-mode approach to determine AChE by multifunctional BSA-MnO2 QDs with oxidase-mimetic activity. A visible color signal was induced by BSA-MnO2 QDs which exhibit good oxidase-mimetic activity to oxidize 3, 3′, 5, 5′-tetramethylbenzidine (TMB) to blue oxide; by employing AChE to hydrolyze acetylthiocholine (ATCh), the generated thiocholine (TCh) can inhibit BSA-MnO2 QDs activity, that displayed an outstanding fluorescence signal but the oxidase-mimetic activity decreased. Following this principle, dual-mode determination of AChE with high sensitivity was achieved. By analyzing real samples, it was verified that the method demonstrated excellent interference tolerance and reliability. In addition to having excellent properties and practicability, the proffered dual-mode method was likely to be an effective method for detecting AChE with high efficiency and reliability.