Engineering PLGA doped PCL microspheres with a layered architecture and an island–sea topography

Abstract

Composite polymer devices have gained considerable interest in biomedical applications. In this work, a composite poly(lactic-co-glycolic acid)/poly(ε-caprolactone) (PLGA/PCL) microsphere with a layered architecture and an island–sea topography was developed. PCL was found to occupy the shell layer of the microsphere, while PLGA constituted surface islands and the internal core. This subtle structure was derived from the different external and internal rates of phase separation between PCL and PLGA. The existence of the PLGA islands enhanced the hydrophilicity of the PCL shell. Mouse mesenchymal stem cells (mMSCs) were cultured and they grew well on the PLGA/PCL microspheres. The surface of the microsphere was microscopically composed of PCL sea and PLGA islands, and the mMSCs showed a trend to attach to the more hydrophilic PLGA islands and bridged between adjacent microspheres. This paper provides a new alternative to design functional microspheres for potential application in tissue repair.