Untitled

Abstract

We performed an experimental study on a new drug delivery system that employs a porous hydroxyapatite block (HAb) (composition: Ca10(PO4)6(OH)2)) to conduct sustained release of a chemotherapeutic agent. To confirm penetration of the agent into the HAb (2 cm3), an aqueous solution containing eosin dye was used at various vacuum pressures. To estimate the storage capacity of the HAb, blocks were weighed before and after being impregnated with the aqueous dye solutions, and the capacity of the block was calculated from the increase in weight after vacuum. In this slow-release study using vacuum, the anti-cancer drug methotrexate (MTX) was used in vitro. Four HAb (1 cm3) containing different concentrations of MTX, ranging from 1.22 to 2.38 mg per block, were studied. All were found to release the drug, maintaining a mean concentration of 0.22 to 0.32 microg/ml even after twelve days. This concentration is high enough to be effective against tumor cells. The results suggest that HAb impregnated with a chemotherapeutic agent using a simple vacuum system may serve as a valuable new method of administering local chemotherapy, primarily when used as a strut graft for bone defects. This new drug delivery system can also be used as an adjuvant material in extended curettage, which can also discourage recurrence of benign tumors without any risk of systemic toxicity.

Nanocrystalline hydroxyapatite and zinc-doped hydroxyapatite as carrier material for controlled delivery of ciprofloxacin

“…By this method the drug action is localized and maintained for a long time. In spite of high drug concentration at the infection site the systemic side effects is low (Itokazu et al 1999). By having a localized drug delivery we can maintain a high concentration of drug for a long time at the specific infected bone site by controlling the release of drug.…”

Novel fabrication of forsterite scaffold with improved mechanical properties

“…In fact, porous bioceramics have been used for bone defect filling, implant fixation via bone ingrowth (i.e. biological fixation), bone regeneration via tissue engineering [2][3][4], drug delivery [5][6][7][8], cell loading [9,10], and ocular implant [11]. However, it is challenging to control and optimize the porous structures (e.g.…”

Modification of Apatite Materials for Bone Tissue Engineering and Drug Delivery Carriers

“…In addition to bone regeneration, attempts have been made to use apatite materials in the treatment of bone inflammation and tumors [102][103][104][105][106][107].…”