QUANTITATIVE DETERMINATION OF MONOMECAINE METHOD NONAQUEOUS ACIDIMETRY
The purpose of this study is to develop methods of quantitative determination of biologically active compounds of monomecaine (2-methylanilide-N,N-diethylaminoethanic acid nitrate), showing a pronounced antiarrhythmic activity. The article presents a scheme of the synthesis and physico-chemical properties of monomecaine. As a potential antiarrhythmic drug the title compound is recommended for pre-clinical studies, therefore, it is necessary to develop a quality standard, the part of which is a method for quantitative determination. Monomecaine belongs to the class of salts formed with an organic base and a mineral acid. For such compounds in pharmaceutical analysis is used the method of the nonaqueous acidimetry in the medium of the protogenic solvent. The article represents the results of determination of the pKa the value of the compound and the choice of the optimal composition of the protogenoi solvent, the method of testing. It is shown that the optimal non-aqueous solvent in the titration is a mixture of acetic acid and anhydrous acetic anhydride in the ratio 5:10, titrant – perchloric acid, the method of indication – potentiometric. The validation techniques for parameters are: linearity, precision and accuracy of the results showed that it met the acceptance in the criteria for analytical purposes (RSD not more than 0,04 %, not more than 0,08 %).