Preparation and solubility profile study of sodium and potassium salts of mefenamic acid: the effect of pH and polarity

Enhancing the solubility of active pharmaceutical ingredients became a fundamental concept in the manufacturing of different pharmaceutical dosage forms. This research aims to enhance the solubility of mefenamic acid by salt formation method and study the effect of polarity, pH, and temperature on the solubility of mefenamic acid and its salts. Two deferent salts of mefenamic acid (sodium and potassium salts) were prepared. Using the asymmetric factorial as an experimental design, the solubility of mefenamic acid (MA), sodium mefenamate (Na-MA), and potassium mefenamate (K-MA) were studied in different solvents, pH, and temperatures. It has been found that potassium mefenamate has the highest solubility among other derivatives in different media. Also, the mefenamic acid and its salts have a higher solubility in the polar aprotic solvent and the higher pH aqueous media.