Low level detection of nonionic surfactants of pharmaceutical interest

Abstract

Nonionic surfactants are used in the pharmaceutical industry in a variety of formulations. For solid dosage forms, surfactants are sued to improve drug solubility, flow properties in manufacturing or the efficacy or bioperformance of the formulation by altering the thermodynamic activity, solubility, diffusion, disintegration, and dissolution rate. Because most commercial surfactants lack a chromophore, charged aerosol, evaporative light scattering, or refractive index detectors are used in their analysis. Recently in our laboratory, we had a need to measure the release of the tablet coating for a series of tablets. Because the tablet coating used a surfactant unique to the dosage formulation, monitoring the release of this surfactant could act as a surrogate for the release of the coating. However, because of their low formulation concentrations, these traditional detectors used with surfactants were not suitable for measuring surfactants in pharmaceutical dissolution testing. A novel application of the boron doped diamond (BDD) electrode for the sensitive detection of nonionic surfactants is presented. Using the RP-Amide column, characteristic profiles for several commercial surfactants shown along with the linear regression evaluation of the specific groups in these profiles used for quantification.