Fig. 4

Real-time measurement of ROS and temperature in adherent HeLa cells during photothermal-chemotherapy treatment.

a Schematic illustration of intracellular temperature and ROS detection, Ti₃C₂@DOX was endocytosed by HeLa cells. Under NIR irradiation, both intracellular temperature and ROS concentration increased, as detected by the nanoprobe. b Intracellular current traces measured by the nanoprobe in HeLa cells with Ti₃C₂@DOX (orange) and without Ti₃C₂@DOX (gray). c Quantification of intracellular ROS concentrations in 19 individual cells (inset shows the nanoprobe inserted into a Ti₃C₂@DOX-treated HeLa cell). d Thermoelectric potential traces collected from the nanoprobe when penetrating (blue) and positioned near (gray) a single HeLa cell after treatment with 20 µg/mL Ti₃C₂@DOX and NIR irradiation. e Thermoelectric potential traces collected from the nanoprobe during cell penetration (blue) and when positioned near (gray) a single HeLa cell after treatment with a lower concentration of 5 µg/mL Ti₃C₂@DOX and exposure to NIR irradiation. f Thermoelectric potential traces of a single HeLa cell treated with Ti₃C₂@DOX under different NIR intensities