The Preparation of Bone-Mimetic Sol-Gel Nanoporous Scaffold of L3-Phase Silica/Hydroxyapatite

Abstract

This work presented the highly controlled drug delivery system to achieve the suppression of the burst release at initial time and long term release of drug with cancellous bone mimetic nanoporous structures. The materials were prepared by the integration of synthesized inorganic hydroxyapatite (HA) and the hybrid gels of bicontinuous sponge-phased L 3 silicate and thermo-responsive poly(Nisopropylacrylamide) (L 3 -PNIPAm gels). The materials were designed to have the three dimensionally interconnected heterogeneous porosity of macro-and mesoporosity, in which the HA has the macroporosity of 150 to be impregnated the drug into the pores and the L 3 -PNIPAm gels have mesoporosity of 5 nm to regulate the temperature sensitive drug-release through the pore channels and polymeric network, respectively. Consequently, these bone-mimetic system gave the highly long term drug release over the 60 days with suppressing the burst release and was able to control the releasing rate per time by the change of the HA and PNIPAm composition ratios.