Today, liposomes are among the most applied technologies for the encapsulation and delivery of bioactive agents and many different compounds in biological, pharmaceutical, medical and nutritional research. In this review, classification of liposomal vesicles, methods of their preparation and encapsulation, as well as their applications in food, cosmetics and pharmaceutical industries are reviewed. In addition, the main analytical approaches used to study liposome characteristics such as size, transition temperature, surface charge, fluidity, lamellarity, stability and encapsulation efficiency are presented. In the final part of the article, mechanisms of liposome targeting are discussed.
A simplified method to study rehydration was used on different dairy powders. The method involved dispersing powder in a stirred vessel equipped with a turbidity sensor. The changes of turbidity occurring during powder rehydration highlighted the rehydration stage, and the influence of the proteins' state on rehydration was clarified. Casein powders had a quick wetting time but very slow dispersion, making the total rehydration process time-consuming. On the other hand, whey powders were found to have poor wettability but demonstrated immediate dispersion after wetting. Mixing casein (80%) and whey (20%) before spray drying greatly improved rehydration time compared with casein powder; whereas mixing whey powder with casein powder at the same ratio after spray drying caused a dramatic deterioration in the rehydration properties. Moreover, agglomeration was found to significantly improve the rehydration time of whey protein powder and to slow down the rehydration time of casein powder. These opposite effects were related to the rate-controlling stage (i.e., wetting stage for whey protein and dispersion stage for casein).
1 April 2006 in Colloids and Surfaces B: Biointerfaces