Water Soluble Cationic Porphyrin Sensor for Detection of Hg²⁺, Pb²⁺, Cd²⁺, and Cu²⁺

Figure 5

The electronic absorption spectra of aqueous solution of (a) 1-Pb ²⁺ (5.0 × 10⁻⁶ M 1 and 5.0 × 10⁻⁶ M Pb²⁺) upon addition of increasing amount [0.50, 1.00, and 1.5 (×10⁻⁶ M)] of Cd²⁺ ions: the inset is the absorption of 1-M ²⁺ versus [Cd²⁺] (pink curve is the absorption at 447 nm and brown curve is the absorption at 478 nm), and (b) 1-Hg ²⁺ (5.0 × 10⁻⁶ M 1 and 5.0 × 10⁻⁶M Hg²⁺) upon addition of increasing amount 0.50, 1.00, 1.50, and 2.5 (×10⁻⁶ M) of Cd²⁺ ions.

(a)

(b)