Investigation of preparation and biocompatibility of injectable chitosan-collagen-based hydrogels

An injectable new-type temperature-sensitive hydrogel consisted of chitosan-glycerophosphate-collagen (C-GP-Co) was prepared and the biocompability for adipose tissue-derived stem cells (ADSCs) was detected. The C-GP-Co hydrogel was prepared as follows: chitosan solution (2.2%, volume fraction) and β-glycerophosphate solution (50%, mass fraction) were mixed at a series of proportion, and then, the collagen solution (2 mg/mL) was added into the previous mixture to get the C-GP-Co hydrogel. The gelation time was measured at 37°C, and the osmotic pressure of the media within the hydrogels was measured, and then, the micro structure analysis was carried out by SEM. The isolated, cultured and identified ADSCs were seeded into C-GP-Co hydrogels and cell growth status was observed under inverted microscope. The cell apoptosis was detected using Live/Dead Viability-Cytotoxicity Kit, while the proliferation of ADSCs was determined by CCK-8 kits. The experimental results show that the gelation time is about 12 min at 37°C, the osmotic pressure of media in the hydrogel is in the normal range of 310-330 mmol/kg and the inner structure of hydrogel is spongy porous. And later, the biocompability of the C-GP-Co hydrogel was further examined. After 7 days' culture, cells within C-GP-Co hydrogels display adherent cell morphology and high cell viability. It is demonstrated that the C-GP-Co hydrogel has excellent cell compatibility and is a proper scaffold for ADSCs proliferation.