A Reproducible Surface Plasmon Resonance Immunochip for the Label-Free Detection of Amantadine in Animal-Derived Foods

A novel surface plasmon resonance (SPR) immunosuppression chip was developed for the reproducible and label-free detection of amantadine (AM) in animal-derived foods. Under the optimal conditions, the proposed SPR immunochip presented a good signal response to AM in the concentration range of 0.05–25.0 ng mL−1, exhibiting high sensitivity (IC50 4.0 ng mL−1) and a low detection limit (IC15 1.3 ng mL−1) and cross-reactivity (rimantadine 16%; others < 1%). Each chip could be reused for 60 times with good stability. Further, sample loading/chip regeneration/baseline recovery was completed within 6 min. The spiked and recovery experiments presented acceptable recoveries, 80.2–102.9% with good precision (relative standard deviation [RSD, n = 3] ≤ 5.2%) in the selected matrix samples, being confirmed using an HPLC–MS/MS method with a correlation coefficient (r2) of 0.98. This proposed SPR immunochip provides a reliable, fast, and cost-effective analytical strategy, with superior potential for extension to the qualitative and quantitative analyses of other analytes in other fields.