Determination of Total Germanium in Chinese Herbal Remedies by Square-Wave Catalytic Adsorptive Cathodic Stripping Voltammetry at an Improved Bismuth Film Electrode

Figure 3

Cyclic voltammograms recorded at a BiFE plated in 1 mol L⁻¹ acetate buffer (pH 4.5) containing 0.08 mol/L trisodium citrate: (a) 0.1 mol L⁻¹ HAc-NaAc (pH 4.8) + pyrogallol (1.3×10⁻³ mol L⁻¹) + 2×10⁻⁴ mol L⁻¹ KBrO₃; (b) a + Ge(IV) (20 μg L⁻¹); deposition potential: −0.34 V; deposition time: 150 s; potential scan rate: 50 mV s⁻¹.