Hela cell culturing on a hydrophilicity controlled silicon nitride surface

Cell culture on a silicon nitride membrane is required for atmospheric scanning electron microscopy, electron beam excitation-assisted optical microscopy, and various biological sensors. Cell adhesion to a silicon nitride membrane is weak, and the proliferation potential is also limited. Therefore, we considered that the adhesion force and proliferation potential of cultured cells might be increased by controlling the surface hy-drophilicity. In this study, we covalently coupled carboxyl groups on silicon nitride membranes to increase the hydrophilicity. We measured contact angles of water droplets on silicon nitride membrane surfaces to evaluate the hydrophilicity. Moreover, we successfully cultured HeLa cells on coated membranes. Cell migration and confluence were observed on the coated silicon nitride film.