Array arrangement of living cells on self-assembled-monolayer pattern chip with femtosecond laser inducing mechanical force "micro tsunami"

We have developed a novel method for arranging living cells on a glass chip with micrometer-scale cell-adhering areas by applying femtosecod laser. To form the cell-adhesion area, the chip surface was first covalently modified with perfluoroalkyl self-assembled-monolayer (R_f-SAM) and then etched by oxygen-plasma. The R_f-surface and the etched surface were characterized using solvent contact-angle analysis. It was confirmed that the R_f-surface has low surface-free-energy as contact angle was 118.2deg and 69.0deg with water and hexadecane, respectively. Thus the R_f-surface has repellent characteristics for polar and nonpolar materials. Protein adsorption on the fabricated R_f-micropattern chip was evaluated using R-phycoerythrin. There was little signal derived from R-phycoerythrin on the R_f-surface indicating that R_f-SAM inhibits the protein adsorption onto the surface. When mammalian PC12 cells were cultured on the R_f-micropattern chip, the cells adhered and grew up only on the etched glass surface but not on R_f-surface. Cultured cells were detached one by one from a culture substrate and transported onto a specific cell-adhering area on the R_f-micropattern chip by using femtosecond-laser-induced mechanical force that we named "micro tsunami".