Cell volume measurement using scanning ion conductance microscopy

We report a novel scanning ion conductance microscopy (SICM) technique for assessing the volume of living cells, which allows quantitative, high-resol ution characterization of dynamic changes in cell volume while retaining th e cell functionality. The technique can measure a wide range of volumes fro m 10(-19) to 10(-9) liter, The cell volume, as well as the volume of small cellular structures such as lamelopodia, dendrites, processes, or microvill i, can be measured with the 2.5 x 10(-20) liter resolution. The sample does not require any preliminary preparation before cell volume measurement. Bo th cell volume and surface characteristics can be simultaneously and contin uously assessed during relatively long experiments. The SICM method can als o be used for rapid estimation of the changes in cell volume. These are imp ortant when monitoring the cell responses to different physiological stimul i.