Micropatterning of HeLa cells on glass substrates and evaluation of respiratory activity using microelectrodes

The micropatterns of mammalian cells (HeLa cells) were prepared on glass substrates, and the respiration of the patterned cells was studied by microelectrode techniques, mainly by scanning electrochemical microscopy (SECM). The cellular patterns on a micrometer scale were prepared by microcontact printing of an extracellular matrix protein, fibronectin, onto a hydrophobic glass plate. The oxygen concentration in the vicinity of the patterned cells was mapped by scanning a Pt microelectrode, and the obtained SECM images proved that the cells in patterns were living with the uptake of oxygen. HeLa cells in the band patterns were well spread, while the cells in the small island patterns were restricted in their shape. The respiratory activities of these cells were evaluated by measuring the difference in the oxygen concentration between the bulk solution and the cell surface, and it was shown that a spreading cell consumed a significantly larger amount of oxygen than a round cell.