The biomimetic system of oleanolic acid and oleic acid at the air-water interface–interactions in terms of nanotechnology-based drug delivery systems
[ 1 ] Instytut Technologii i Inżynierii Chemicznej, Wydział Technologii Chemicznej, Politechnika Poznańska | [ D ] phd student | [ P ] employee
2022
scientific article
english
- oleanolic acid
- oleic acid
- mixed monolayer
- phase separation
- excess free energy of mixing
- dilatational rheology
- interface stability
- biomimetic system
- phytomedicine
EN Oleanolic acid (OLA) and oleic acid (OA) are ubiquitous in the plant kingdom, exhibiting a therapeutic effect on human health, and are components of novel pharmaceutical formulations. Since OLA has limited solubility, the utilization of nanotechnology-based drug delivery systems enhancing bioavailability is highly advantageous. We report on the interfacial behavior of the OLA:OA system at various molar ratios, using the Langmuir technique to assess the dependence of the molar composition on miscibility and rheological properties affecting film stability. Specifically, we evaluate the interfacial properties (morphology, thermodynamics, miscibility, and viscoelasticity) of the OLA:OA binary system in various molar ratios, and indicate how the OLA:OA system exhibits the most favorable molecular interactions. We apply the Langmuir monolayer technique along with the complementary techniques of Brewster angle microscopy, dilatational interfacial rheology, and excess free energy calculations. Results demonstrate that the properties of mixed monolayers depend on OLA:OA molar ratio. Most of the systems (OLA:OA 2:1, 1:1, 1:5) are assumed to be immiscible at surface pressures >10 mN/m. Moreover, the OLA:OA 1:2 is immiscible over the entire surface pressure range. However, the existence of miscibility between molecules of OLA and OA in the 5:1 for every surface pressure tested suggests that OA molecules incorporate into the OLA lattice structure, improving the stability of the mixed film. The results are discussed in terms of providing physicochemical insights into the behavior of the OLA:OA systems at the interface, which is of high interest in pharmaceutical design.
1215-1 - 1215-15
Article number: 1215
CC BY (attribution alone)
open journal
final published version
01.12.2022
at the time of publication
public
100
4,2