Development of an aptamer-based SPR-biosensor for the determination of kanamycin residues in foods

• Published in: Analytica chimica acta Vol. 1169; p. 338631
• Main Authors: Écija-Arenas, Ángela, Kirchner, Eva-Maria, Hirsch, Thomas, Fernández-Romero, Juan Manuel
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 18-07-2021
• Subjects: Aptamer sensor; Graphene support; Kanamycin residues detection; Raman spectroscopy; Surface plasmon resonance spectroscopy; Aptamer sensor; Kanamycin residues detection; Surface plasmon resonance spectroscopy; Raman spectroscopy; Graphene support
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2021.338631

A biosensor in which an affinity reaction occurs in the sensitive microzone through the use of specific aptamers to determine kanamycin residues in agri-food samples has been developed. It is an irreversible and continuous flow aptameric biosensor (aptasensor) in which the signal variations are monitored by surface plasmon resonance (SPR) measurements based on the specific interaction of the aptamer with the antibiotic. The signal variation is proportional to the analyte concentration. Graphene is known for efficient binding of molecules with its π-electron system, so a monolayer of graphene prepared from chemical vapor deposition (CVD) has been compared to a multilayer of graphene made from reduced graphene oxide (rGO) for immobilization of the aptamer on the gold surface of the physicochemical transducer. The best results have been obtained with CVD graphene. The dynamic range was between 1 and 100 μmol L−1 of kanamycin concentration (r2 = 0.9981, n = 7, r = 4), with a limit of detection of 285 nmol L−1 and a sampling frequency of 6 h−1. The precision, expressed as relative standard deviation (RSD%), was established in the range of 1.49 and 3.89%, calculated for 1, 10, and 50 μmol L−1. The selectivity was studied applying the described method to determine other antibiotics, obtaining no significant difference in the analytical signal. The method was applied to determine kanamycin residues in milk samples with recovery values ranging between 90 and 96%.
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•A biosensor based on the use of specific aptamer biding have been developed.•The aptamer was immobilized at the sensor surface using two types of graphene.•Chemical vapor deposition graphene and reduced graphene oxide were compared as sustrate surface.•The union of the analyte was monitored by surface plasmon resonance.•The aptasensor was applied to the kanamycin determination in cow milk samples.