Determination of Mefenamic Acid Using a New Mode of Irradiation (Array of Six Identical LEDs) and Detection( Twin Solar Cells) Through Turbidity Measurement by CFIA


A newly developed analytical method characterized by its speed and sensitivity for the determination of mefenamic acid (MFA) in pure and pharmaceutical preparation is established via turbidimetric measurement (0-180o) by Ayah 6SX1-ST-2D Solar cell CFI Analyser . The method was based on the reaction of phosphomolybdic acid with mefenamic acid in aqueous medium to form blue color precipitate as an ion-pair complex . Turbidity was measured via the reflection of incident light that collides on the surface precipitated particles at 0-180o . The chemical and physical parameters were studied and optimized. The calibration graph was linear in the range of 0.3-7 or 0.3-10 mMol.L-1, with correlation coefficient r = 0.9907 or 0.9556 respectively. The limit of detection 4.92 µg/sample from the step wise dilution for the minimum concentration in the linear dynamic ranged of the calibration graph with RSD% lower than 0.3% for 3 and 5 mMol.L-1 ( n= 6,10 respectively ) concentration of mefenamic acid. The method was successfully applied to the determination of mefenamic acid in four pharmaceuticals . A comparison was made between the newly developed method analysis and the classical method , in addition to between four different pharmaceutical preparations (UV- spectrophotometry at wave length 288 nm) using the standard additions method via the use of t-test. It was noticed that there was no significant difference between two methods at 95 % confidence level and significant difference between four drugs.