Figure 4

UV-Vis. absorption spectra and change of reaction colours (inset) for AgNPs probe based detection of Hg²⁺ in the range of 20–200 ppm in SDDW (a) and tap water (c); plot of ΔAbs (change in absorbance) against concentration of Hg²⁺ in SDDW (b) and tap water (d).