The work outlined herein describes an evaluation of a green solvent working as a drug solubility and penetration enhancer made up of a deep eutectic system (DES) composed of menthol (MN) and capric acid (CA). Risperidone (RIS) was tested as a class II model drug. The system efficacy in enhancing drug solubility was carried out at five different CA: MN mass ratios (w/w) of 7:3, 6:4, 5:5, 4:6, and 3:7. The 7:3 CA:MN (w/w) mass showed the most remarkable solubility improvement of the drug of up to 73000-fold compared to water. The phase-forming mechanics involved in drug-related solubility were demonstrated in this work by studying the mixtures’ viscosity and contact angle at the same above-mentioned CA:MA ratios. Moreover, the interactions between the components that constitute the DES were studied using DSC and FTIR analysis. Results confirmed that H-bonds between MN and CA formed the DES. The permeability of the systems was established through diffusion studies carried out using Franz cell. Preparations comprising the drug in DES showed the absence of any acute skin irritation/erosion effect on Wistar rats.
By Saifeddin Daadoue, Mayyas Al-Remawi, Layaly Al-Mawla, Nasir Idkaidek, Ruwaida M. Khalid, Faisal Al-Akayleh