Alogliptin (AGLT), active ingredient of Alogliptin Benzoate (AGLT-BZ), is a new dipeptidyl
peptidase-4 (DPP-4) inhibitor for the treatment of type 2 diabetes. This study aimed to build
a suitable method to determine the potential related substances in AGLT-BZ bulk drug and
tablets. Seven related substances in Alogliptin Benzoate substances were synthetized and
identified by 1
H-NMR and ESI-MS. In addition, the impurities were detected by a gradient
reverse-phase high performance liquid chromatography (RP-HPLC) with UV detection. The
chromatographic system consisted of an Angilent Zobax SB-CN column (250 4.6 mm;
5 mm). The mobile phase consisted of water/acetonitrile/trifluoroacetic acid 1900:100:1 v/v/
v (solution A) and acetonitrile/water/trifluoroacetic acid 1900:100:1 v/v/v (solution B) using
a gradient program at a flow rate of 1.0 ml/min with 278 nm detection and an injection
volume of 20 ml. Additionally, selectivity, the limit of quantitation (LOQ) and limit of
detection (LOD), linearity, accuracy, precision and robustness were determined. Linearity
was good over the concentration range 50e1000 ng/ml and the coefficient of determination
(R2
) were 0.9991e0.9998. RSD% of the determination of precision were