Figure 3

Performances of the single-indicator-based sensing platform to individuals of metal ions.

(a) Color images of the dithizone-CTAB mixture before and after exposure to different concentrations of Cd²⁺ and Hg²⁺, along with the color difference maps. For purposes of visualization, the color difference maps were expanded from 4 to 8 bits per color (RGB range of 4–19 expanded to 0–255). (b,c) The total Euclidean distances of the dithizone solution in the absence and presence of CTAB versus different concentrations of Hg²⁺ (b) and Cd²⁺ (c). (d) PCA plot for the discrimination of Hg²⁺ and Cd²⁺ at different concentrations based on the RGB alterations of the dithizone-CTAB system. The experiments were performed in triplicate with 30 μM dithizone in the presence of 90 μM CTAB in 10 mM HEPES buffer at pH 7.4. The error bars in Fig. (b,c) represent the standard deviations of triplicate experiments.