Eutectics in Pharmacy Curriculum: A Simple Demonstration with Pharmaceutical Relevance

Abstract

In chemistry, a eutectic mixture refers to a mixture of two or more components at which the lowest possible freezing point is observed. This phenomenon is covered in a wide range of curricula such as physics, chemistry, chemical engineering, and pharmacy to various depths. Despite the significance of this phenomenon in pharmaceutical compounding and formulation, standard pharmacy curricula provide only limited coverage of the eutectic mixture and the theoretical aspects associated with its phase diagram. A practical session on a eutectic mixture should augment the theoretical pedagogical component and enable a more profound understanding. Despite the existence of educational publications that discuss this phenomenon from a chemical perspective, there is currently no reported experimental laboratory specifically focused on the eutectic phenomenon and its implications in the field of pharmacy. In this study, we employ camphor and menthol as pharmaceutical active ingredients that illustrate a robust eutectic phenomenon within practical temperature ranges. Moreover, we utilize the eutectic phenomenon and the resulting liquefaction effect upon mixing camphor and menthol to prepare semisolid pharmaceutical dosage forms (gels and rubs), demonstrating to students the impact of this phenomenon in drug compounding and formulation.