Optimization of gallic acid encapsulation in calcium alginate microbeads using Box-Behnken Experimental Design

Abstract

The aim of this study was the optimization of the gallic acid (GA) encapsulation efficiency within calcium alginate microparticles by the ionotropic gelation technique, using Box-Behnken design for the surface methodology response. For this purpose, three independent variables were selected: sodium alginate concentration (X1), calcium chloride concentration (X2), and gallic acid concentrations (X3). The influence of each variable on the encapsulation efficiency was evaluated. The optimum conditions to reach maximum encapsulation efficiency were found to be: X1 = 30 g/l (3%, w/v), X2 = 21.63 g/l (2.163%, w/v) and X3 = 15 g/l (1.5%, w/v), respectively. The encapsulation efficiency was determined to be 42.8%. The obtained microbeads were further examined using differential scanning calorimetry (DSC) and Fourier transform infrared (ATR-FTIR), and the inclusion of gallic acid was confirmed. The gallic acid concentration (X3) is the statistically significant factor in the optimization process. In addition, no autoxidation of the gallic acid compound was observed in the formulated calcium alginate microbeads. Scanning electron microscope (SEM) analysis showed that the shape of the particle was spherical for all formulations and their surface is wrinkled. The release study of the gallic acid carried out in an aqueous medium at pH value 6.8, showed that the GA release pattern was fast for all systems studied (85% at 20 min), and the profile of the release was influenced by the size of the calcium alginate microbeads. The obtained results reveal that the calcium alginate microbeads prepared through the ionotropic gelation technique possess great prominent for gallic acid encapsulation as well as its liberation.

Use of New Glycerol-Based Dendrimers for Essential Oils Encapsulation: Optimization of Stirring Time and Rate Using a Plackett—Burman Design and a Surface Response Methodology

“…On the opposite, the rate of encapsulation is quite lower than encapsulation by coacervation in gelatin optimized by Sutaphanit P. and Chitprasert P. (66.5 to 98.4%) but the release from these capsules is almost impossible (stable for 18 months storage) [30]. In another field of application, optimized encapsulation of gallic acid in calcium alginate microbeads was of the same order (42.8%) [31]. In the context of the use of dendrimer-EOs formulations as biopesticide, it is essential to go further in the study of the encapsulation rate with a dynamic study of the release of EOs by the dendrimer.…”

Influence of Sodium Alginate Concentration on Microcapsules Properties Foreseeing the Protection and Controlled Release of Bioactive Substances

“…Calcium alginate microcapsules containing bioactive substances were prepared using the ionotropic gelation method under optimal formulation as described previously in our works [8]. Briefly, 3-6% (w/v) of the sodium alginate and 1.5% (w/v) of bioactive substance were dissolved in 100 ml of distilled water.…”

“…e release of bioactive substances from the elaborated microparticles in an aqueous medium was achieved using the UV-visible spectrophotometer. e analysis was realized based on our previously described method [8]. Briefly, a known amount of microcapsules was suspended in 100 ml of distilled water.…”

“…e sequence and ratio (M/G) of these uronic acids vary with the origin of alginate and control their properties [7]. A broad range of application can be found in food and pharmaceutical industries due to the biocompatibility, biodegradability, and nontoxicity of this biomaterial and also to their gelling properties when it crosslinked with divalent ions such as calcium and ferrous cation [3,[8][9][10]. Sodium alginate polymer, obtained from brown algae, has a number of features that makes it particularly appropriate to form hydrogel microcapsules, such as its low cost, high availability, biodegradability, biocompatibility with other agents, and easy synthesis of microparticles [3,8,11,12].…”

“…A broad range of application can be found in food and pharmaceutical industries due to the biocompatibility, biodegradability, and nontoxicity of this biomaterial and also to their gelling properties when it crosslinked with divalent ions such as calcium and ferrous cation [3,[8][9][10]. Sodium alginate polymer, obtained from brown algae, has a number of features that makes it particularly appropriate to form hydrogel microcapsules, such as its low cost, high availability, biodegradability, biocompatibility with other agents, and easy synthesis of microparticles [3,8,11,12]. e application area of alginate microcapsules is mainly depending on the properties presented by those microcapsules, which make it necessary to determine their physicochemical, mechanical, and structural properties.…”