Optimization of analytical methods based on non-linear asymptotic calibration graphs. Effect of the Time of Hydrolysis on the Enzymatic Determination of Pyridostigmine

A method for enzymatic determination of pyridostigmine is considered. The nonlinear calibration graphs obtained are functions of nine independent variables. The optimization of the curves is discussed, with the relative error as the criterion of optimization. A graphical method is suggested, which allows easy determination of the relative error, of the best concentration for sampling, and of the limit of response. A shortcut method of optimization for asymptotic calibration curves is suggested, and illustrated by optimizing the time of hydrolysis of acetylcholine by cholinesterase. Some determinations of pyridostigmine in water, urine and bovine serum are presented, employing the suggested method.