Hydroxyapatite-armored poly(ε-caprolactone) microspheres and hydroxyapatite microcapsules fabricated via a Pickering emulsion route

• Published in: Journal of colloid and interface science 2012-05, Vol.374 (1), p.1-8
• Main Authors: Fujii, Syuji, Okada, Masahiro, Nishimura, Taiki, Maeda, Hayata, Sugimoto, Tatsuya, Hamasaki, Hiroyuki, Furuzono, Tsutomu, Nakamura, Yoshinobu
• Format: Article
• Language: English
• Subjects: Biocompatible Materials - chemical synthesis; Capsules; Chemistry; Colloidal state and disperse state; Desiccation; Durapatite - chemistry; Electron Probe Microanalysis; Emulsions; Emulsions - chemistry; Emulsions. Microemulsions. Foams; Energy dispersive; evaporation; Exact sciences and technology; General and physical chemistry; Hybrid; Hydrogen-Ion Concentration; Hydroxyapatite; Microscopy, Electron, Scanning; Microsphere; Microspheres; Nanocomposites; Nanomaterials; nanoparticles; Nanoparticles - chemistry; Nanostructure; oil-water interface; Oils - chemistry; Particle Size; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Pickering emulsion; Poly(ε-caprolactone); Polyesters - chemistry; pyrolysis; scanning electron microscopy; solvents; Surface physical chemistry; surfactants; Thermogravimetry; Water - chemistry; X-rays
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2012.01.058

[Display omitted] ► Apatite-poly(ε-caprolactone) particles are fabricated from Pickering emulsions. ► Apatite capsules are fabricated from apatite-poly(ε-caprolactone) particles. ► The diameters of apatite-poly(ε-caprolactone) particles can be successfully controlled. Hydroxyapatite (HAp) nanoparticle-armored poly(ε-caprolactone) (PCL) microspheres were fabricated via a “Pickering-type” emulsion solvent evaporation method in the absence of any molecular surfactants. It was clarified that the interaction between carbonyl/carboxylic acid groups of PCL and the HAp nanoparticles at an oil–water interface played a crucial role in the preparation of the stable Pickering-type emulsions and the HAp nanoparticle-armored microspheres. The HAp nanoparticle-armored PCL microspheres were characterized in terms of size, size distribution, morphology, and chemical compositions using scanning electron microscopy, laser diffraction, energy dispersive X-ray microanalysis, and thermogravimetric analysis. The presence of HAp nanoparticles at the surface of the microspheres was confirmed by scanning electron microscopy and energy dispersive X-ray microanalysis. Pyrolysis of the PCL cores led to the formation of the corresponding HAp hollow microcapsules.