A combined chitosan/nano-size hydroxyapatite system for the controlled release of icariin

Abstract

Icariin, a plant-derived flavonol glycoside, has been proved as an osteoinductive agent for bone regeneration. For this reason, we developed an icariin-loaded chitosan/nano-sized hydroxyapatite (IC-CS/HA) system which controls the release kinetics of icariin to enhance bone repairing. First, by Fourier transform infrared spectroscopy, we found that icariin was stable in the system developed without undergoing any chemical changes. On the other hand, X-ray diffraction, scanning electron microscopy and mechanical test revealed that the introduction of icariin did not remarkably change the phase, morphology, porosity and mechanical strength of the CS/HA composite. Then the hydrolytic degradation and drug release kinetics in vitro were investigated by incubation in phosphate buffered saline solution. The results indicated that the icariin was released in a temporally controlled manner and the release kinetics could be governed by degradation of both chitosan and hydroxyapatite matrix. Finally the in vitro bioactivity assay revealed that the loaded icariin was biologically active as evidenced by stimulation of bone marrow derived stroma cell alkaline phosphatase activity and formation of mineralized nodules. This successful IC-CS/HA system offers a new delivery method of osteoinductive agents and a useful scaffold design for bone regeneration.

Icariin-Loaded TiO2 Nanotubes for Regulation of the Bioactivity of Bone Marrow Cells

“…A recent study reported the generation of a novel bone repair scaffold consisting of a chitosan/nanosized hydroxyapatite system loaded with ICA that can control the release rate and extent of ICA and enhance bone repair. The in vitro bioactivity assay revealed that the loaded ICA was biologically active [22]. ICA increases bone marrow cells differentiation and bone mineralization most likely by upregulating the expression of NO synthesis, subsequently regulating Cbfa1/Runx2 [23,24].…”

Development of Composite Scaffolds for Load Bearing Segmental Bone Defects

“…SBDs are defined as injuries in which a section of bone is completely shattered and/or absent. Usually, the size of the missing section is large enough that bone either cannot regenerate on its own (critical sized defects) or results in the formation of pseudoarthrosis (nonunions), malunions, and loss of function, making corrective surgery or additional fixation using metallic fixators a common complication [14][15][16][17][18][19][20][21][22][23].…”

“…HAp [23,44,46,51,[59][60][61][62] is the most commonly used ceramic biomaterial in orthopedic applications because of its biocompatibility [63][64][65]. HAp scaffolds stimulate cell attachment, growth, and differentiation [23,48,66], even though they degrade at a very slow rate [67]. -tricalcium phosphate ( -TCP) is the second most widely used CaP ceramic in bioengineering, and its alkaline nature makes it a good candidate for hybrid scaffolds to counteract the acidity resulting from polymer breakdown [8,27,46,62,68].…”

“…The greatest concern with HAp specifically, and with ceramics in general, is that they cannot be used alone for load-bearing applications due to the brittleness (failure due to lack of plastic deformation) of these materials and the overall poor mechanical properties [20, 21, 23, 24, 26, 38, 39, 44, 59, 61, 63, 65-67, 76, 80, 85, 86]. In addition, CaP ceramics degrade very slowly [23,26,60,85,87,88]. In contrast, fast CaP degradation is also not necessarily beneficial for tissue regeneration.…”

Preparation of chitosan/nano hydroxyapatite organic–inorganic hybrid microspheres for bone repair

“…ICA, the extract of traditional Chinese medicine-epimedium, has been proved as an osteoinductive agent for regeneration. Fan et al [23] and Yang et al [24] found that the combination of ICA and scaffold was biologically active and could promote the proliferation of osteoblasts in vitro bioactivity assay.…”