In vitro delivery of dexamethasone using hydroxyapatite reservoirs.
Dexamethasone has been shown to stimulate bone nodule formation in vitro. A hydroxyapatite (HA) reservoir drug release device was designed to release dexamethasone in vitro. Two HA particle sizes (< 38 microns or 63-75 microns) were used to fabricate the reservoirs. Each HA reservoir was loaded with 2 mg of dexamethasone and suspended in 100 ml of 50% aqueous ethanol at 37 degrees C for a period of 28 days. The positive controls indicated a limited solubility of dexamethasone of 1.18 mg per 100 ml of 50% aqueous ethanol. Dexamethasone was not released from any of the HA reservoirs for the first 24 hours. The largest amount of dexamethasone (0.0137 microgram/microliter) was released from the 63-75 microns particle HA reservoirs. A significantly lesser amount (0.00855 microgram/microliter) of dexamethasone was released from the < 38 microns particle HA reservoirs. The results of this study suggest that a HA ceramic reservoir loaded with dexamethasone can be used to deliver dexamethasone over long periods of time.
Billotte
W G
WG
Biology Department, University of Dayton, Ohio 45469-2320, USA.
Bajpai
P K
PK
D001672:Biocompatible Materials; D003907:Dexamethasone / Q000008:administration & dosage*; D016503:Drug Delivery Systems; D017886:Durapatite; D005938:Glucocorticoids / Q000008:administration & dosage*
D001672:Biocompatible Materials; D005938:Glucocorticoids; D003907:Dexamethasone; D017886:Durapatite