Figure 2

(a) Rubidium uptake by adherent CHO cells in a K⁺-free buffer over a period of two hours. (b) Percentage of Rubidium uptake by adherent CHO cells treated with various concentrations of Ouabain with respect to untreated cells in (a). Ouabain inhibits the Na⁺/K⁺ ATPase pumps. (c) Potassium and Rubidium concentration inside CHO cells in a K⁺-free buffer (0–90 min) and subsequently in a Rb⁺-free buffer (90–180 min). The error bars represent the minimum and maximum values of the ion concentrations for three repeated measurements reported by ICP-OES.