Hollow polymer microspheres have attracted great attention in tissue regeneration as cell carrier. In this study, hollow poly(lactic-co-glycolic acid)/hydroxyapatite/calcium carbonate (PLGA/HA/CC) microspheres with porous surface were successfully fabricated using bioactive minerals as in situ pore-forming agents. No templates were introduced in this facile approach. The capability of HA to hold water contributed to the formation of the porous surface and the hollow structure. Furthermore, the gas-releasing effect originating from CC decomposition facilitated the generation of opened superficial macropores. Porcine mesenchymal stem cells (PMSCs) were cultured on the microspheres and the results highlighted a better proliferation on microspheres with opened macropores. Therefore, this subtly designed microsphere shows a potential application in cell delivery.
