A Highly Sensitive Electrochemical Sensor Based on Electrocatalytic Reduction Effect of Cu²⁺ on Trace Determination of Malathion in Soil and Other Complex Matrices

Figure 2

SW-CSVs of the supporting electrolyte at pH 2 (black line), in the presence of Cu²⁺ ions (green line), and in the presence of malathion and Cu²⁺ ions (red line). Conditions: [Malathion] = 6 × 10⁻⁸ M, [copper (II)] = 3.4 × 10⁻⁷ M, E_acc = –0.2 V; t_acc = 120 s; sweep rate = 0.1 V/s, pulse amplitude of 50 mV, and frequency 60 Hz.