A new approach to the production of zein microstructures with vitamin B12, by electrospinning and spray drying techniques

Abstract

In this study, vitamin B12, the most chemically complex and the largest molecule among all the vitamins, was successfully incorporated into zein microstructures via electrospinning and spray drying techniques. Scanning electron microscopy analysis revealed that different microstructures were obtained by electrospinning tech-nique: films, microparticles and electrospun fibres. The vitamin B12 films presented a smooth surface and had around 90% of encapsulation efficiency. Vitamin B12-encapsulated zein microbeads, with a size of around 3 mu m, were formed showing an efficiency of encapsulation of 91%. Electrospun fibres exhibited ribbon-shaped morphologies and had an encapsulation efficiency of 100%. By spray drying technique, wrinkled zein micropar-ticles with vitamin B12 were produced with an encapsulation efficiency and product yield ranging between 71 and 95% and 67-83%, respectively. Kinetic models were applied to the experimental release profiles. The Weibull kinetic model showed the best fitting with the experimental data. The main drug transport mechanism associated to the experimental data is the Fickian diffusion (case I transport). The results suggest that the produced zein microstructures via spray drying and electrospinning techniques can be used as promising and effective alternative food and nutraceutical delivery systems.