Spectrophotometric methods based on 2,6-dichloroindophenol acetate and indoxylacetate for butyrylcholinesterase activity assay in plasma

► Spectrophotometric methods for assay of butyrylcholinesterase are proposed. ► 2,6-dichloroindophenol acetate and indoxylacetate were compared to standard Ellman's method. ► Biochemical parameters such as KM and VMAX were calculated for the substrates. ► The methods were calibrated using pure butyrylcholinesterase. ► The methods were verified using human plasma.