The invention provides a method for determining the content of
clenbuterol hydrochloride in an
ambroxol oral solution, which comprises the following steps: respectively injecting a
diluent, a reference solution and a
test solution into a two-dimensional high performance liquid chromatograph, recording chromatograms, and calculating the content of
clenbuterol hydrochloride by
peak area according to an external standard method. The first-dimensional liquid
chromatography conditions are as follows: a
phosphoric acid buffer solution-
methanol-
acetonitrile is taken as a mobile phase A,
methanol is taken as a mobile phase B, and
gradient elution is carried out; the second-dimensional liquid
chromatography conditions are as follows:
phosphoric acid buffer solution-
methanol-
acetonitrile is taken as a mobile phase A, and switching is performed according to a specific program. The detection method disclosed by the invention is simple and convenient, the interference of a matrix in a sample can be well solved, the
peak area response of a main component can be increased by about 5 times compared with that of a common high-performance
liquid phase, and the
detection limit is as low as 0.02 mu g / ml; the method is good in
system applicability, good in specificity, good in
repeatability, high in accuracy and good in solution stability, and can be used for quantitatively detecting the content of
clenbuterol hydrochloride in the
medicine.