An antifouling electrochemical sensor based on a U-shaped four-in-one peptide and poly(3,4-ethylenedioxythiophene) for vancomycin detection in fresh goat milk

• Published in: Food chemistry Vol. 463; no. Pt 1; p. 141056
• Main Authors: Li, Yonghui, Pu, Xujun, Ding, Yangyue, Yi, Lunzhao, Yang, Yukun, Gu, Ying, Wang, Shuo
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.01.2025
• Subjects: Antifouling; Food safety; Peptide; Sensor; Vancomycin; Food safety; Vancomycin; Peptide; Antifouling; Sensor
• ISSN: 0308-8146; 1873-7072; 1873-7072
• DOI: 10.1016/j.foodchem.2024.141056

Nonspecific adsorption of biomolecules (notably, proteins) and bacteria from unsterilized food may occur on sensor surfaces, which is still a challenge for food safety sensing. To achieve sensitive detection of unsterilized raw-food materials, in this study, a U-shaped four-in-one peptide with the sequence Ac-FLKLLKKLL-DOPA3-PPPPEEKDQDKEKaa that exhibited anchoring, antifouling, antibacterial, and recognition properties was designed. The peptide-modified sensor surface effectively prevented bacterial adhesion and proliferation while resisting biomolecule adsorption (signal inhibition rate as low as 0.51 % in single-protein solutions). A highly conductive polymer layer of poly(3,4-ethylenedioxythiophene) was introduced to improve the electrochemical performance before U-shaped four-in-one peptide anchoring. The proposed sensor could accurately detect vancomycin, with a wide linear range and limit of detection of 0.05–10 μg mL−1 and 2.06 ng mL−1 (S/N = 3), respectively. Satisfactory recovery rates (101.3–105.3 %) were achieved using diluted fresh goat milk. •A U-shaped four-in-one peptide (Ac-FLKLLKKLL-DOPA3-PPPPEEKDQDKEKaa) was designed.•The four-in-one peptide simplifies the construction of the sensor.•The proposed sensor can effectively detect Van residues in diluted fresh goat milk.