Synthesis and preliminary in vivo evaluations of polyurethane microstructures for transdermal drug delivery

BACKGROUND Polymers have been considered as important materials in fabrication of microstructures for various medical purposes including drug delivery. This study evaluates polyurethane as material for hollow microstructures preparation. RESULTS Polyurethane microstructures were obtained by interfacial polyaddition combined with spontaneous emulsification and present slightly acid pH values. Scanning electron microscopy revealed the existence of irregular shapes and agglomerated microstructures. The material is heat resistant up to 280°C. Good results were recorded on murine skin tests in case of polyurethane microstructures based on isophorone diisocyanate. Mesenchymal stem cells viability presents good results for the same sample after 48 hours based on the Alamar Blue test. CONCLUSIONS The research revealed the reduced noxiousness of this type of microstructures and consequently the possibility of their use for therapeutic purposes.