An assay for detecting, measuring, or monitoring the activity or
concentration of at least two proteins that have similar or overlapping
properties is disclosed. The assay comprises first determining the
sensitivity coefficients of the substrates for each of the proteins in
which the concentrations are to be determined. This method may be used for
detecting, measuring, or monitoring the activity and concentration of
AChE, BChE, or both in a test sample which test sample may be whole and
unprocessed blood or tissue. Also disclosed are methods of using the assay
to detect a subject's exposure to an agent which affects cholinesterase,
determine the efficacy or progress of a treatment, determine the amount of
protection provided against exposure to an agent which affects
cholinesterase, or both, screen a subject for having a drug sensitivity or
a particular disease, detect a change in red blood cell count of a
subject, determine whether a candidate compound affects cholinesterase.
Also disclosed are devices and kits for detecting, measuring, or
monitoring the activities and concentrations of AChE, BChE, or both.
