APPLICATION OF DIFFERENTIAL SCANNING CALORIMETRY TO THE STUDY OF LATEX STABILITY

Differential scanning calorimetry was used to study the effect of temp erature, shaking, and pH on the stability of an aqueous dispersion of ethylcellulose latex particles (Aquacoat(TM), 0.3 mum in diameter) obt ained by emulsion polymerization, and frequently used as an excipient in pharmaceutical formulations. Of the three factors studied, pH had t he most marked effect on latex stability, followed by shaking and temp erature. We conclude that differential scanning calorimetry is a relia ble method for the study of factors that modify the stability of some components of pharmaceutical formulations.