Figure 2

Performances of the sensor for sensing pH.
Sensitivity and Response behavior of the sensor when exposed to the pH buffer solution changing from pH 7.0 and pH 9.0 (A). The pH response calibration curve based on the RGB read-outreferencing ratiometric method (B); error bars represent the standard deviation (SD) of the mean (n = 3). Cross-sensitivity towards varying ionic strength (C) and temperature (D); the response curves in (A,B) were obtained at IS = 0.03 M and 25 °C, while all calibration curves presented in (C,D) were obtained in the laboratory with the same sensing film and with phosphate/NaCl buffer solutions.