Nafion/Silver Nanoparticles as an Electrochemically Sensitive Interface for the Detection of Ractopamine in Pork Liver

High Resolution Image Download MS PowerPoint Slide Many countries have allowed farmers to feed β-adrenergic receptor agonists, such as ractopamine (Rac), to animals to improve the quality of their meat. However, Rac consumption can cause health problems for humans; thus, detecting Rac in meat before its packaging is essential. Consequently, this study developed a simple and sensitive electrochemical sensor by modifying a glassy carbon electrode (GCE) with Nafion/silver nanoparticles (Nafion/AgNPs). When this electrochemical sensor is used to detect Rac, electrostatic interaction occurs between Nafion and Rac, and the AgNPs oxidize Rac; thus, the accumulation and electrochemical sensing of Rac are achieved. Differential pulse voltammetry indicated that the as-prepared Nafion/AgNP-GCE sensor exhibited suitable electrochemical sensing ability under optimum conditions (6.0 μL of 0.10% Nafion/AgNPs in a Britton–Robertson buffer solution with a pH of 1.8, an accumulation potential of −0.2 V, and a Rac accumulation duration of 300 s). Moreover, this sensor has an extremely low limit of detection and high sensitivity (1.60 × 10 –3 ppm and 2.14 μA/ppm, respectively) in the Rac concentration range 7.50 × 10 –3 –1.00 ppm. The as-prepared sensor also exhibits satisfactory reproducibility and storage stability, with the corresponding relative standard deviations (RSDs) being 4.27% ( n = 5) and 1.56% ( n = 10), respectively. The proposed electrochemical sensor was successfully used to determine the Rac content in pig liver samples, with spiked recoveries of 95.2–101.8% and RSDs of 0.55–4.83% being achieved.