Preparation of nano/macroporous polycaprolactone microspheres for an injectable cell delivery system using room temperature ionic liquid and camphene

The nano/macroporous polycaprolactone (PCL) microspheres with cell active surfaces were developed as an injectable cell delivery system. Room temperature ionic liquid (RTIL) and camphene were used as a liquid mold and a porogen, respectively. Various-sized spheres of 244-601μm with pores of various size and shape of 0.02-100μm, were formed depending on the camphene/RTIL ratio (0.8-2.6). To give cell activity, the surface of porous microspheres were further modified with nerve growth factors (NGF) containing gelatin to give a thin NGF/gelatin layer, to which the neural progenitor cells (PC-12) attached and extended their neurites on to the surface layers of the microspheres. The developed microspheres may be potentially applicable as a neuronal cell delivery scaffold for neuron tissue engineering.