ANALYTICAL METHOD FOR 1-METHYL-4-AMINO-PIPERAZINE IN AN ACTIVE PHARMACEUTICAL INGREDIENT USING CHEMICAL DERIVATIZATION AND HPLC-UV

Abstract

A method to form a UV-active derivative of 1-methyl-4-amino-piperazine (AMP) was developed. The method was based on the reaction of AMP with benzaldehyde, forming a stable derivative, which was UV-active. The method was used to analyze samples of an active pharmaceutical ingredient (API) for trace amounts of AMP. The derivatization approach allowed detection of AMP at low levels, using readily available HPLC-UV instrumentation. The method was validated in the range of about 30 to 190 ppm (on a mass to mass basis relative to API). It was shown through spiked recovery tests that the derivatization reaction occurred smoothly without interference from the API. The results suggest that other organohydrazine compounds may be amenable to the same derivatization technique.

Keywords:

• benzaldehyde
• benzylidene
• derivatization
• hydrazine
• hydrazone
• organohydrazine