Paper-based amperometric sensor for determination of acetylcholinesterase using screen-printed graphene electrode

A simple paper-based sensor with electrochemical detection was first developed for rapid, selective, and sensitive determination of acetylcholinesterase (AChE). The screen-printed graphene electrode was used as working electrode providing sensitivity for the sensor. The amperometric detection of AChE is based on the determination of thiocholine (TCh) produced from hydrolysis of acetylthiocholine chloride (ATCh) by AChE. To detect TCh, the ATCh immobilized sheet was stacked onto the detection sheet using double adhesive tape, then samples of AChE were dropped on the back side of an ATCh immobilized sheet with only 1min of incubation time. To avoid interference, glutathione (GSH), the potential of 0.5V vs. Ag/AgCl was applied onto a graphene electrode and the current, which depends on AChE concentration, was measured. Under optimized conditions, the limit of detection (LOD) from the experiment of AChE determination was 0.1U/mL with AChE concentration in range of 0.1–15U/mL. The data correlated well with the data obtained using spectrophotometric method. The developed sensor had been successfully applied to detect AChE in blood samples. [Display omitted] •The paper-based amperometric sensor was successfully developed for AChE determination.•The screen-printed graphene electrode is easy to prepare and shows high sensitivity.•This device shows high selectivity for AChE determination.•A new design platform provides the device with long term storage.•The sensor can be applied for AChE determination in blood sample.