Rheological Properties of Nanoemulsions Stabilized by Polysorbate 80

Abstract

The rheological properties of nanoemulsions based on three types of oil phases, namely, Crodamol GTCC, Crodamol PC, and oleic acid, were analyzed and determined. The emulsions were stabilized by Polysorbate 80. Geranic acid was selected as a model active substance. The obtained results confirm that the studied nanoemulsions are pseudoplastic non-Newtonian fluids. The Herschel-Bulkley model accurately describes the rheological properties of the developed systems. The phase inversion point for the Crodamol GTCC/Polysorbate 80/water system was observed at 50 wt % dispersed-phase concentration. The rheological results served as the basis for calculation of a theoretical diffusion coefficient of the active ingredient in the studied nanoemulsions.

The effect of alcohols as vehicles on the percutaneous absorption and skin retention of ibuprofen modified with l-valine alkyl esters

“…This results in loosening the lipid layer and increasing its uidity and consequently increases the degree of diffusion of active compounds. 59,63 Almost for each compound, there is the same tendency of an increase in the cumulative mass of ibuprofen that permeated through the skin, expressed as mg IBU cm À2 , with the change of the alcohol as a vehicle, in the sequence from methanol through ethanol to i-propanol, for both acceptors phases pH 5.4 and 7.4 (Table 4). It means, that i-propanol is the best enhancer of skin permeation of both unmodied ibuprofen and its salts with L- ).…”

In Vitro and Ex Vivo Evaluation of Mangifera indica L. Extract-Loaded Green Nanoparticles in Topical Emulsion against Oxidative Stress and Aging

“…Measures were as viscosity = f time . The viscosity (f time ) allows measuring at an immobile shear rate throughout a determined time [ 39 ]. Measuring protocols were pre-shearing time; 5 s, pre-shearing rate: 10 S 1; shear rate: 50 S 1; time: 60 s; and an immediate start.…”

Preparation of O/W nano-emulsion containing nettle and fenugreek extract and cumin essential oil for evaluating antidiabetic properties

“…Rheology is the study of the flow of matter that deals with the deformation and flow of materials (Mehrnia et al, 2017). Rheological analysis plays a very important role in the design of release systems (Jaworska et al, 2015). Rheology tests were performed to determine viscosity of NEs at different shear rates (until 1000 s −1 ).…”

“…If the emulsion is a system with a high degree of dispersion, the interaction between the particles is weak. However, if the number of droplets increases, the interaction between them becomes stronger and at the same time the viscosity of the whole system increases (Jaworska et al, 2015).…”