Evaluation of linagliptin dissolution from tablets using HPLC and UV methods

Abstract

Linagliptin (LGT) is used to reduce glucose blood levels in patients with type 2 Diabetes mellitus. The proposed conditions for a biowaiver guide can be applied due to high solubility of linagliptin in aqueous media. The aim of the present study was to develop and validate a dissolution test for 5 mg linagliptin coated tablets. After diverse dissolution procedure evaluation, the selected method was achieved using USP apparatus 1 (basket) at 75 rpm and 900 mL of citrate buffer pH 3.5 as dissolution medium. The conditions proposed by biowaiver guide were also applied to this drug, using USP apparatus 2 (paddle) and 900 mL of 0.1 M HCl, pH 4.5 acetate buffer and pH 6.8 phosphate buffer as dissolution medium. HPLC and UV spectrophotometry were used to LGT quantitation and validated for this purpose. The chromatographic and spectrophotometric methods in the dissolution context proved to be linear in 0.5 – 20.0 μg.mL^-1 range, precise with RSD values less than 1.0 % and 2.0%, respectively, and accurate (mean recovery 100.29 % and 100.59%). The parameters such as specificity, linearity, accuracy, precision and robustness were according to international guidelines for both methods HPLC and UV. Dissolved linagliptin results were compared using the Student’s t-test and the data found were not significant different (P=0.068). In most dissolution conditions evaluated, LGT presented more than 85% drug dissolved from the tablets in fifteen minutes. The proposed methods can be applied for quality control of this gliptin. According to the results, linagliptin may be a biowaiver candidate.