Adsorption and drug release based on β-cyclodextrin-grafted hydroxyapatite composite

摘要

In this study, β-cyclodextrin (β-CD) was covalently grafted on hydroxyapatite (HA) using a coupling agent to improve the drug loading capacity and prolong the drug release. The binding of β-CD on the HA surface was confirmed by Fourier transformation infrared spectroscopy, thermal gravimetric analysis, and X-ray powder diffraction. The adsorption capacity of ofloxacin on β-CD-grafted hydroxyapatite (β-CD-g-HA) composite was found to be 30 mg g~(-1) at 37°C and 24 h. The adsorption process is spontaneous, given the negative values of free energy change. Compared with the release of ofloxacin loaded on HA, the release of ofloxacin loaded on β-CD-g-HA was slowed down 28% and 21% in pH 2.0 and pH 7.4 buffer media at 2 h, respectively. Biocompatibility of β-CD-g-HA was assessed by MTT assay, and the result showed that it had no cytotoxicity.