For BChE/AChE-selective inhibitor controls, 50 µL aliquots of plasma were preincubated for 10 min with 0.5 µL of the respective inhibitor stock solution, giving final concentration of 500 µM ethopropazine, 100 µM isoOMPA, or 100 µM BW284c51, respectively, then the carbamate was added and the sample incubated for 30 min at room temperature. Recombinant hBChE and hAChE were diluted with PBS to 0.5 mg/mL and 50 µL aliquots were used as described for plasma. The click reaction followed a reported protocol. Briefly, the samples were then diluted with 400 µL PBS and the following reagents were added, vortexing after each addition: 20) for 1 h at room temperature. The membranes were washed thrice with TTBS buffer for 5 min at room temperature, followed by a 12 h incubation at 4 °C in the primary antibody solution (1:500 rabbit anti-hBChE antibody ab236577, Abcam, in 3% BSA in TTBS). The membranes were then washed thrice with TTBS buffer for 5 min at room temperature and incubated in the secondary antibody solution (1:5000 goat anti-rabbit IgG-HRP conjugate, Jackson ImmunoResearch 111-035-045, in 5% milk in TTBS) for 1 h at room temperature. The membranes were finally washed six times with TTBS buffer for 5 min at room temperature and exposed for 5 min to 700 μL of the chemiluminescent reagent (SuperSignal™ West Femto Maximum Sensitivity Substrate, Thermo Fisher Scientific). Chemiluminescence was observed in an imaging device (G-box, Syngene) in the dark.