Validation of a Stability-Indicating Assay Method for the Determination of Ibuprofen in a Tablet Formulation

Abstract

Ibuprofen, a derivative of propionic acid, is an anti-inflammatory and analgesic frequently used in the treatment of pain. However, ibuprofen is not immune to counterfeiting. The main objective of this work was to validate a stability-indicating HPLC method for ibuprofen and to apply it to the quality control of a tablet formulation. The chromatographic conditions were a C18 column (125 mm × 4.6 mm, 5 μm), a mobile phase consisting of a mixture of acetonitrile/triethylamine buffer at pH 7.05 (60:40, v/v) at a flow rate of 1.5 ml/min, an injection volume of 10 μl, and UV detection at 220 nm. Validation included linearity, repeatability, accuracy (n = 3) by spiked additions, limit of detection (LOD), and limit of quantification (LOQ). The validated method was used for the analysis of an ibuprofen tablet formulation. Forced degradation studies were performed by exposing the ibuprofen standard solution to acid (HCl; 1 N), base (NaOH; 1 N), and an oxidizing agent (10% H2O2) for 24 to 48 hours. The calibration curve showed a linearity range between 5.33 μg/ml and 16 μg/ml of ibuprofen. The LOD and LOQ were 0.447 μg/ml and 1.356 μg/ml, respectively. The recovery rate expressing accuracy was 100.45%. The repeatability CVs were all less than 2%. The analyzed sample had a compliant ibuprofen content. Forced degradation studies showed degradation of the molecule under basic conditions, with the identification of impurity C. The ibuprofen molecule was stable under acidic and oxidative conditions. The method applied to the analysis of a tablet formulation showed a compliant ibuprofen content of 103.51% and the absence of degradation products.