Novel fabrication techniques to produce microspheres by thermally induced phase separation for tissue engineering and drug delivery.
A novel application of thermally induced phase separation (TIPS) is described enabling the rapid formation of monodisperse porous microspheres. By taking advantage of TIPS processing parameters, the porosity, the pore morphology (bimodal/channel-like/radial towards the centre) and the presence of an open-pore or dense skin region can be tailored. Achievable sizes range from 10 to 2000microm in diameter. The technique facilitates the homogeneous inclusion of particulate fillers and drugs. Moreover, the combined TIPS/oil-in-water emulsion technique allows for the production of microspheres with isotropic pore morphology with interconnected spherical pores of 30-70microm and well-formed porous microspheres of 10-200microm in diameter with an open porous surface. This method is advantageous over existing techniques by avoiding the use of long-term exposure to an aqueous continuous phase as used in oil-in-water or water-in-oil-in-water processing and therefore drug encapsulation efficiencies will be higher.
Blaker
Jonny J
JJ
Biomaterials and Tissue Engineering Group, Burdette Institute of Gastrointestinal Nursing, Kings College London, UK.
Knowles
Jonathan C
JC
Day
Richard M
RM
D001672:Biocompatible Materials; D016503:Drug Delivery Systems / Q000379:methods*; D019344:Lactic Acid; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D012235:Rhodamines; D023822:Tissue Engineering / Q000379:methods*
D001672:Biocompatible Materials; D012235:Rhodamines; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; C009434:tetramethylrhodamine isothiocyanate