Figure 2.

A) Redox signal stability, as assessed by the relative decrease in peak current ( $i/i_0$ ), of 1.HB_SAM upon repeated SWV cycling in ACN/H₂O 99 : 1, 100 mM TBAClO₄ in the presence (green triangles) and absence (black circles) of 10 mM HClO₄. The measurements in the absence of acid were terminated after 250 scans. The stability at intermediate acid concentrations is shown in Figure S2.1. B) Potential response of 1.HB_SAM in ACN/H₂O 99 : 1, 10 mM HClO₄ in the alternating absence and presence of 0 or 50 mM HSO₄ ⁻.