Figure 4

The effect of pH (A) on the response of ECL intensity from Au@Pb-β-CD/GCE without Cr(VI) (black column) and with 500 nM Cr(VI) (red column); The effect of concentration of K₂S₂O₈ (B) on the response of ECL intensity from Au@Pb-β-CD/GCE. Error bars = RSD (n = 3).