Fig. 5.

(A) Schematic illustration of the simultaneous release of Dex and Mg²⁺ from HA -BP–Mg nanocomposite hydrogel to enhance stem cell osteogenesis. The expression of ALP catalyzes the dephosphorylation of DexP, which accelerates the release of Dex at bone defect sites. (B) i) Drug loading and ii) drug release of MgSiO₃ NPs from the colloidal hydrogel. When the NPs are injected into the acidic microenvironment, the MgSiO₃ NPs are released due to the protonation of BP and the disruption of chelation with Mg²⁺. Reproduced with permission from Refs. [77], copyright 2016, Royal Society of Chemistry.