Efficient Fabrication of Polymer Shell Colloidosomes by a Spray Drying Process

Colloidosomes have been extensively studied in recent years because of their potential applications in various fields, such as food, cosmetics, or pharmaceutical industries. Herein, we present a simple and highly efficient route for large-scale preparation of colloidosomes with controllable permeability using spray drying technology. By using the latex particles with different glass transition temperatures, the colloidosomes with uniform and controllable shell porosities can be easily constructed. The effects of latex particle concentrations, flow rates of compressed air, inlet temperatures, and feed rates on the morphologies of colloidosomes were explored in detail, and the possible formation mechanism was given. Both the feed rates and inlet temperatures can affect the evaporation rate of solvents. Only the preparation conditions falling on the suitable speed of the solvent evaporation “area” can result in complete colloidosomes. In addition, the Congo red dye was used as a model for encapsulation and controllable release. The release duration of colloidosomes prepared with different Tg latex particles ranged from 23 to 52 h as the permeability drops. The results demonstrate that this colloidosome fabrication method is feasible for continuous large-scale production and precisely controllable release for practical applications.