Aerosol-Mediated Fabrication of Porous Thin Films Using Ultrasonic Nebulization

Abstract

High surface area ceramic films and biopolymer films were fabricated by precipitation at room temperature of a reagent aerosol composed of approximately 1 μm diameter microdroplets laid onto a reactive receiver solution using a completely enclosed system. Calcium phosphate films of up to 340 μm in thickness composed of hollow microspheres were generated by gradual settling and precipitation of the reagent microdroplets on the receiver solution surface. Suitability of the ceramic film as a drug support using alendronate as an example was investigated. Chitosan/alginate biopolymer films were similarly prepared and precipitation with limitation to the air/water interface promoted a wire form copper oxide precursor. Zirconia microspheres were prepared without use of surfactant or template via precursor precipitation in a stirred receiver solution. Additional components could be readily incorporated and the flexibility of the novel approach is consistent with a new general strategy for the preparation of thin films and hollow microspheres of nanostructured materials.