Electrometrical cholinesterase activity

Michel, H.O. (1949). An electrometric method for the determination of red blood cell and plasma cholinesterase activity. J. Lab. Clin. Med. 34 1564-8. 

Methods for the detection of cholinesterase activity can generally be divided into four groups, electrometric, colorimetric,titrimetric and tintometric methods, with the last being the one mainly used in the field. The colorimetric method developed by Ellman et al. is the most frequently used procedure. Titrimetry is extremely accurate and precise, but rarely used because of its high cost and complexity. Electrometric methods are less sensitive than colorimetric methods and less accurate than titrimetric methods. 

Tammelin LE. An electrometric method for the determination of cholinesterase activity. I. Apparatus and cholinesterase in human blood. Scand J Clin Lab Invest 1953 5 267-70. 

Mohammad FK, St Omer VE. Modifications of Michel s electrometric method for rapid measurement of blood cholinesterase activity in animals aminireview. Vet Hum Toxicol 1982 24 119-21. 

FIGURE 19.3 (a) Reaction depicting inhibition of AChE and BChE (in blood, RBC and plasma, respectively) by chemical warfare and pesticide organophosphorous compounds, yielding inhibited enzyme and reduced signal, (b) Summary of methods for measuring cholinesterase activity in blood (only colorimetric and electrometric are shown). See text for abbreviations. 

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