“…AChE activity was measured by a protocol based on Ellman's method, 46 the details of which are described elsewhere. 47,48 In brief, acetylthiocholine iodide (ATChI) was used as the substrate and 5,5 0 -dithio-bis-2-nitrobenzoic acid (DTNB) was the colorimetric agent that produces 5-thio-2-nitrobenzoate, a yellowcoloured species that can be observed spectrophotometrically by measurement of absorbance at 412 nm, on reaction with ATChI. In both the enzymatic and non-enzymatic reactions, the concentration of DTNB was fixed at B317 mM.…”