Procedure for determining the polymorphic purity of the dihydrochloride minidipina.

Procedure for determining the polymorphic purity of the dihydrochloride manidipine. A method is described to determine the polymorphic purity of the polymorph dihydrochloride manidipine \ beta in a pharmaceutical tablet using information obtained by Raman spectroscopy comprising the following steps: i) preparing a series of known samples, each of which comprises an amount of polymorph \ beta and an amount of polymorph \ alpha, where in each of the known samples, the total amount of the compounds remains the same, while their proportion varies; ii) obtain the Raman spectra of several known samples; iii) selecting one or more signals for each wavelength form, so that differences in the spectra of each of the known samples are more noticeable, and so that signals of the excipients do not interfere; iv) performing a statistical analysis of the spectral data of the series of known samples; v) collecting the spectral data of a sample comprising polymorph manidipine dihydrochloride \ beta with an unknown polymorphic purity; Y vi) calculate polymorphic purity of polymorph \ beta.