Identification and quantitation of XXXX impurity by capillary zone electrophoresis-mass spectrometry.

@entity71970 @entity71972 @entity71971 @entity15 @entity5189
@entity71970 was identified and quantified as impurity of @entity71971 , an antifungal compound, by capillary zone electrophoresis-electrospray-mass spectrometry (CZE-ESI- @entity15 ). The chirality of this impurity was demonstrated separating their enantiomers by adding @entity71972 to the separation buffer in capillary electrophoresis (CE) with UV detection. However, @entity15 detection was hyphenated to the CE instrument for its identification. As both compounds are diastereomers, they have the same m/z values and are needed to be separated prior to the @entity15 identification. A 0.4M @entity5189 separation buffer at pH 3.0 enabled the separation of the impurity from @entity71971 . Under these conditions, the optimization of ESI- @entity15 parameters (composition and flow of the sheath-liquid, drying temperature, drying gas flow, and capillary potential) was carried out to obtain the best @entity15 sensitivity. CZE-ESI- @entity15 optimized conditions enabled the identification of @entity71970 as impurity of @entity71971 . In addition, the quantitation of this impurity was achieved in different samples: @entity71971 standard and three different pharmaceutical formulations (two tablets and one syrup) containing this standard. In all cases, percentages higher than 2.0 were determined for the impurity. According to ICH guidelines, these values required the identification and quantitation of any impurity in drug substances and products.
