FIG. 3.

The validation of agarose gel-based microfluidic device for chemotaxis assay of C. reinhardtii using NH₄Cl (ammonium chloride; AC), CoCl₂ (cobalt chloride; CC), and NaCl (sodium chloride; SC). All data and error bars are the means and standard deviations of the three biological replicates (n = 3). (a) The number of accumulated C. reinhardtii cells in the observation region in response to NH₄Cl gradient according to time. (b) CI measured in the presence of NH₄Cl gradient after 8 h of observation. (c) A representative microscopy image showing the cell response towards NH₄⁺ after 8 h at different concentrations. (d) The number of the accumulated cells in the observation region towards CoCl₂ according to time. (e) CI measured in the presence of CoCl₂ gradient after 8 h. (f) A representative microscopy image showing the cell response towards Co²⁺ at 8 h at different concentrations. (g) The number of the accumulated cells in the observation region in response to NaCl gradient according to time. (h) CI measured in the presence of NaCl gradient after 8 h. (i) A representative microscopy image showing the cell response towards NaCl at 8 h at different concentrations.