Figure 6

Color variations of (a) anthocyanin solution and (b) BCNF-ANT sensor (Cu(II) 400 ppm) at different pHs, changes in absorbance intensity of (c) anthocyanin solution and (d) BCNF-ANT sensor at 516 nm upon sensing Cu(II) (400 ppm) in aqueous media at various pHs, (e) the ΔE values in various pHs.