Calcium Alginate as a Novel Sealing Agent for Colloidosomes.

We report on the preparation of colloidosomes formed with a poly(methyl methacrylate-co-butyl acrylate) latex shell, sealed using calcium alginate as a novel nontoxic and biodegradable sealing agent. The aim is to encapsulate enzymes in detergent formulations. The proposed method, with vegetable oil as the continuous phase, avoids the use of harmful organic solvents. Allura Red has been used as a water-soluble dye, in the core, to analyze the influence of variables such as sodium alginate and latex concentrations on the sealing and release profiles. After formation, the capsules were dispersed in either water or propylene glycol. The capsules have been examined using optical, confocal, and scanning electron microscopies. Working with the highest sodium alginate concentration and latex volume, the encapsulation efficiency is between 60 and 80%. Propylene glycol enables a better dispersion of the capsules compared with water. Dye release data have been fitted to exponential and Michaelis-Menten-type equations, leading to kinetic parameters that allow the simulation of the release process.