The application discloses a detection method for N-methyl
piperazine in
clozapine, and belongs to the technical field of
drug detection. The detection method comprises solution preparation and detection. The solution preparation uses
clozapine to prepare a
test sample solution and uses N-methyl
piperazine to prepare a
control sample solution. The detection adopts liquid
chromatography-
mass spectrometry to determine the
test sample solution and the
control sample solution, records a chromatogram, and calculates the content of N-methyl
piperazine. In the detection, the conditions of the liquid
chromatography are as follows: a mobile phase is composed of mobile phase A and mobile phase B, the mobile phase A is a 0.048-0.052%
trifluoroacetic acid aqueous solution, and the mobile phase B is
acetonitrile. The application can quantitatively detect the genotoxic
impurity N-methyl piperazine in
clozapine bulk drug and preparations, is convenient for monitoring the content of the
impurity in the production and storage process of clozapine, and is high in selectivity, good in sensitivity, and low in quantitative limit to 0.165 ppm.