Release Kinetic Studies of Stevia rebaudiana Extract Capsules from Sodium Alginate and Inulin by Ionotropic Gelation

Abstract

is study was oriented towards encapsulation of S. rebaudiana extract and the study of its release kinetics. e desired encapsulation was achieved by the ionotropic gelation method using sodium alginate and inulin of polymeric constituents. Characterization of the capsules was performed by micrometric properties, encapsulation efficiency, in vitro extract release analysis, and biological activity of released extract. e in vitro release profiles from different capsules were applied on different kinetic models. e prepared capsules were found spherical in shape with diameters ranging from 2.07 to 2.63 mm, having the encapsulation efficiencies of 43.77% and 56.53% for phenolic compounds and steviol glycosides, respectively. e best-fit model with the highest correlation coefficient was observed in the Ritger-Peppas model, indicating diffusion controlled principle. e release exponent n value obtained from the Korsmeyer-Peppas model varied between 0.2273 and 1.1719, confirming that the mechanism of S. rebaudiana extract bioactive compounds release was diffusion controlled.

Encapsulation of Concentrated Solution Obtained by Block Freeze Concentration in Calcium Alginate and Corn Starch Calcium Alginate Hydrogel Beads

“…For n, the values are less than 0.5 for all samples, ranging from 0.14 to 0.32, and therefore, the release of gallic acid is governed by a diffusion behavior [58,59], meaning that the hydrogel beads follow a pseudo-Fickian diffusion mechanism [60], and in turn, it indicates that the solution diffusion is greater than the relaxation process of the polymeric chain [61].…”

Composite Fish Collagen-Hyaluronate Based Lyophilized Scaffolds Modified with Sodium Alginate for Potential Treatment of Chronic Wounds

“…In addition, the results indicate a time dependent impact of the scaffolds on the cell viability and proliferation with lower percentages after 24 h (especially for the blank A diffusion coefficient n ≤ 0.5 indicates that the release is controlled by Fickian diffusion which is associated with the concentration gradient, diffusion distance, and the degree of swelling [39]. However, the Higuchi model was proven to be suitable to explain the release mechanism of BSA from the SA*:COL:HA 1:1:2 scaffold, which indicates that the release of BSA from the encapsulating matrix into the release medium was unidirectional [49].…”