Temperature measurement for HeLa cells on RT nanosheets upon ionomycin treatment. (A) Time course of changes in Fluo4 F.I. in HeLa cells on RT nanosheets. Gray lines, individual cells; red line, average. Number of cells, 16 (n = 3). (B) Time course of changes in EuTTA F.I. (C and D) Same as in B for the F.I. of Rh101 and the EuTTA/Rh101 F.I. ratio, respectively. Gray lines, F.I. of RT nanosheets in individual cells; red line, average F.I.; blue line; average F.I. of RT nanosheets without cells. Number of cells, 16 (n = 3). (E) Time course of changes in the corrected EuTTA F.I. (F and G) Same as in E for the F.I. of Rh101 and the EuTTA/Rh101 F.I. ratio, respectively. Gray lines, F.I. of RT nanosheets in individual cells; red line, average F.I. F.I. was corrected by that of RT nanosheets without cells. See Materials and methods for details. In each graph, the horizontal black line indicates the period of ionomycin treatment (2 µM, 0.1% DMSO). (H–N) Same as in A–G, respectively, but with 0.1% DMSO (no ionomycin). Number of cells, 10 (n = 2).