Chitosan/Sodium Dodecyl Sulfate Complexes for Microencapsulation of Vitamin E and Its Release Profile—Understanding the Effect of Anionic Surfactant

Abstract

Microencapsulation of bioactive substances is a common strategy for their protection and release rate control. The use of chitosan (Ch) is particularly promising due to its abundance, biocompatibility, and interaction with anionic surfactants to form complexes of different characteristics with relevance for use in microcapsule wall design. In this study, Ch/sodium dodecyl sulfate (SDS) microcapsules, without and with cross-linking agent (formaldehyde (FA) or glutaraldehyde (GA)), were obtained by the spray drying of vitamin E loaded oil-in-water emulsion. All of the microcapsules had good stability during the drying process. Depending on the composition, their product yield, moisture content, and encapsulation efficiency varied between 11–34%, 1.14–1.62%, and 94–126%, respectively. SEM and FTIR analysis results indicate that SDS as well as cross-linkers significantly affected the microcapsule wall properties. The profiles of in vitro vitamin E release from the investigated microcapsules fit with the Korsmeyer-Peppas model (r2 > 0.9). The chemical structure of the anionic surfactant was found to have a significant effect on the vitamin E release mechanism. Ch/SDS coacervates may build a microcapsule wall without toxic crosslinkers. This enabled the combined diffusion/swelling based release mechanism of the encapsulated lipophilic substance, which can be considered favorable for utilization in food and pharmaceutical products.

Load-Bearing Nanostructures in Composites of Chitosan with Anionic Surfactants: Implications for Programmable Mechanomaterials

“…For example, strain-induced polymer crystallization could be applied to mechanically condition CHT, as done commonly with vulcanized rubber, and some polysaccharides. 53 The strain-induced restructuring of SDS micelles could potentially be coupled with SDS's effectiveness in encapsulating a variety of payloads, 27,29,54 similar to previously reported tensile strain-sensing membranous drug delivery systems. 55 These insights may also be relevant to improving the properties of food products, cosmetics, and other consumer products, where SDS:CHT and other polysaccharide−surfactant combinations are routinely used.…”

Coacervating behavior of amino acid anionic and amphoteric mixed micelle-polymer

“…26,27 Studies have shown that different coacervates tend to exhibit distinct morphologies and rheological properties, with “coacervates” providing a smooth sensation and “precipitates” imparting a sticky wet sensation. 22 Furthermore, the structure and viscoelasticity of coacervates are closely related to the encapsulation and release efficiency of actives compounds 28 as well as their skin adhesion properties. Thus, understanding the phase behavior, structure, and rheological properties of coacervates is of great practical importance for the development of personal care formulations.…”

Encapsulation of Amyloglucosidase in Chitosan-SDS Coacervates as a Means to Control Starch Hydrolysis in Plant-Based Beverages

“…A spontaneous liquid/liquid phase separation forms a dense coacervate phase and a dilute equilibrium phase. The coacervates can be created even at surfactant concentrations below the critical micelle concentration and may be stabilised by electrostatic attraction between oppositely charged molecules [31][32][33]. Henceforth, a negatively charged surfactant, sodium dodecyl sulfate (SDS), was utilised to form strong bonds with cationic chitosan, developing insoluble coacervates.…”