The invention relates to a method for detecting related substances in a
chloroquine phosphate tablet. According to the method, the
ultraviolet detector is connected with the
electrospray detector (CAD) in series, so that the
ultraviolet relative
response factor of each
impurity can be quickly, conveniently and accurately calculated, the content of known and unknown impurities in the
chloroquine phosphate tablet can be accurately determined, the sensitivity and specificity of the method are high, and the effective control on related substances of the
chloroquine phosphate tablet is realized. The method comprises the following steps: preparing a
test solution, taking
chloroquine phosphate tablets, dissolving the
chloroquine phosphate tablets with a mobile phase, performing filtering, and taking subsequent filtrate as the
test solution; preparing a
system adaptive solution, namely taking the
test solution, and irradiating the test solution by using an
ultraviolet lamp to obtain the systemadaptive solution; preparing a contrast solution, namely diluting the test solution with a mobile phase to obtain the contrast solution; preparing a reference substance solution, namely dissolving achloroquine phosphate reference substance by using a mobile phase to obtain the reference substance solution; and injecting the
system adaptive solution, the test solution, the reference solution andthe reference solution into a liquid chromatograph for determination.