Modified NLC-loaded coumarin for pharmaceutical applications: the improvement of physical stability and controlled release profile

Abstract

Background: Coumarin-6 is a lipophilic dye and is often used as a model in delivery system.Objective: The aim of this study was to improve the nonstructured lipid carrier (NLC) system loading with lipophilic molecule, coumarin-6, and to investigate its characteristics in terms of physical stability and controlled release profile.Materials and methods: Initially, the selection of the coating polymer was observed. Then, the preparation of the conventional NLC-loaded coumarin-6 was compared to the modified NLC-loaded coumarin-6 via the probe sonication. The physical properties and stability were determined by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques. The release profile was established using fluorescent spectroscopic method.Results and discussion: The size and zeta potential measurement showed significant decrease in the size range of the modified NLC-loaded coumarin and the lower intensity of the surface charge compared to the NLC-loaded coumarin. The change of crystallinity observed from DSC and XRD techniques indicated the molecular dispersion of coumarin-6 in the lipid matrix of NLC. The FT-IR spectra were also proven that coumarin-6 was entrapped in the NLC molecule. The result showed comparable controlled release profile to the conventional preparation with no difference on the cytotoxicity level.Conclusions: The modified NLC delivery system, therefore, exhibited the acceptable potential as a nanocarrier.