Development and characterization of clove oil microemulsion

Abstract

Clove oil is one type of essential oil from clove flower buds (Syzygium aromaticum) which contains eugenol compounds. Clove oil is volatile in nature and highly affected by heat, thus incorporating it in a microemulsion system can increase its shelf life of the oils. This study aimed to formulate and characterize microemulsion preparations with clove flower essential oil. The microemulsion existence region was determined by constructing a pseudo-ternary phase diagrams and prepared with four components, i.e. isopropyl myristate, tween-80 as a surfactant, polyethylene glycol 400 (PEG 400) as a co-surfactant, and water as the aqueous phase. The optimized clove oil microemulsion formulation was subjected to an evaluation of various parameters, such as organoleptic properties, %transmittance, pH, viscosity, stability, particle size, zeta potential, and polydispersity index (IP). Based on the results of the study, the highest compound component in clove oil was eugenol with a % area of ​​63.79%. The results revealed that the construction of a phase diagram and the use of the phase titration method constituted a suitable technique for the preparation of microemulsions as most of the formulations were transparent. It was found that the tween-80:PEG 400 ratio of 2:1 with an oil:S-mix ratio of 1:9 generated an optimum results. The clove oil microemulsion had a globule size of 17.69±0.025nm, a polydispersity index value of 0.057±0.0043, zeta potential of-5.36±0.23mV, and a pH value of 7.3±0.1, a viscosity value of 466.7±9.06., and %transmittance of 99.9±0.1. According to these findings, the microemulsion formulation might serve as a suitable drug delivery system.