Biomimetic Calcium Carbonate Concentric Microgrooves with Tunable Widths for Promoting MC3T3-E1 Cell Functions

Biomimetic, self-assembled calcium carbonate (CaCO3) concentric microgrooves with groove widths of 5.0 and 10 mu m were fabricated through simply controlling incubation temperature. Mouse pre-osteoblastic MC3T3-E1 cells were cultured on flat and microgrooved substrates of CaCO3 and their adhesion, spreading, proliferation, alkaline phosphatase activity, and calcium content were remarkably enhanced by the microgrooves, in particular, the narrower ones. Furthermore, focal adhesions and actin filaments of MC3T3-E1 cells could be aligned on both 5.0-mu m and 10-mu m-wide CaCO3 grooves. Compared with the original round nuclei on the flat substrates and expanded round nuclei on the narrower microgrooves, the MC3T3-E1 cell nuclei on 10-mu m-wide CaCO3 grooves demonstrated preferred entrapment in the grooves and significant alignment with a smaller area after two-day culture.