Hollow hydroxyapatite microsphere: a promising carrier for bone tissue engineering

J Microencapsul. 2016 Aug;33(5):421-426. doi: 10.1080/02652048.2016.1202347. Epub 2016 Jun 29.

Abstract

Hydroxyapatite (HA) microsphere with abundant ordered mesoporous and large hollow structure was prepared at hydrothermal condition with the aid of citrate. The obtained microsphere was performed as a drug delivery carrier to evaluate its drug loading/releasing behaviour using alendronate (AL) as a model drug. Results revealed that HA particles performed high AL-loading capability (46.8 wt % with respect to the powdered starting materials) and excellent AL-releasing behaviour (sustained drug releasing profile without burst release). Besides, although a proliferation inhibition phenomenon was observed as HA and AL-loading HA (HA-AL) co-cultured with mesenchymal stem cells (MSCs) at the initial stage, after prolonging co-culture period, compared with HA and control group, HA-AL promoted the cells' proliferation, meanwhile, it facilitated osteogenic differentiation of MSCs and enhanced the expression level of typical markers, all of that ensure HA microsphere is a promising carrier for bone repair.

Keywords: Hydroxyapatite; alendronate; drug delivery; mesoporous; osteogenesis.