Entrapment Efficiency (EE) and Release Mechanism of Rhodamine B Encapsulated in a Mixture of Chia Seed Mucilage and Sodium Alginate

Chia seed mucilage is a polysaccharide capable of forming hydrogels with excellent water-binding capacity due to its physical and chemical properties and favorable characteristics for encapsulating and protecting valuable hydrophilic molecules in the food, pharmaceutical, and cosmetic industries. This research aimed to show that mixtures of chia seed mucilage and sodium alginate used as wall materials to encapsulate hydrophilic molecules are suitable. We analyzed the relationship between the mucilage–alginate solution’s properties and the capsules obtained; we quantified the entrapment efficiency (EE%) and the release of rhodamine B; and we proposed a method to follow the rhodamine B release using confocal laser scanning microscopy (CLSM). We found that more viscous solutions are obtained when the mucilage concentration increases, making it difficult to produce capsules with less sphericity. The best entrapment efficiency was found when the proportion of the polymers was close to 1:1, based both on the properties of the capsules obtained and on the characterization of the release kinetics of rhodamine B; the analysis performed by fitting rhodamine B release data to theoretical models describe the diffusion process. Our results show that the use of chia seed mucilage as a wall material to trap and retain hydrophilic molecules is convenient.