EFFECT OF SODIUM LAURYL SULFATE AND POLYSORBATE-80 ON CRYSTAL-GROWTH AND AQUEOUS SOLUBILITY OF CARBAMAZEPINE

The effect of sodium lauryl sulphate, an anionic surfactant, and polysorbate 80, a nonionic surfactant, on growth of carbamazepine crystals in aqueous suspensions was studied with the aid of a microscope. In addition, the effect of the surfactants on the aqueous solubility of carbamazepine was determined. Sodium lauryl sulphate accelerated the growth of carbamazepine crystals, probably due to increased solubilization by the surfactant. Polysorbate 80, on the contrary, slowed down the rate of growth and stopped the growth at a certain level. Polysorbate 80, especially at higher concentrations, also changed the growth pattern, and carbamazepine crystals grew markedly in width.