2026-06-08T09:10:49Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/1347172026-04-14T23:55:47Zcom_20.500.14352_14col_20.500.14352_15

00925njm 22002777a 4500 dc Hervás Pérez, Juan Pablo author Sánchez-Paniagua López, Marta author 2025 A label-free electrochemical genosensor for the detection of Ara h2, a major peanut allergen, has been developed using mixed self-assembled monolayers (SAMs) for DNA immobilization. The study used a sandwich format and compared gold nanoparticles-modified screen printed carbon electrodes (AuNPs-SPCE) and screen printed gold electrodes to obtain a highly sensitive bioplatform. Different binary and ternary SAMs were evaluated as sensing phase, by electrochemical impedance spectroscopy and cyclic voltammetry, obtained the best signal to noise ratio with CP-DTT-AuNPs-SPCE. The genosensor demonstrated a linear response in the concentration range of 0.025–10 nM, with a detection limit of 0.02 nM by square wave voltammetry. The precision of the biosensor was validated, showing a RSD of less than 8 % across different concentrations. Selectivity tests confirmed negligible signals for non-complementary sequences. Additionally, the method proved effective in real food matrices, with recovery rates between 95.0 % and 105.5 % in spiked soy-based beverage and low-fat cow’s milk. Hervás-Pérez JP, Sánchez-Paniagua M. Label-free electrochemical DNA biosensor for detection of peanut allergen Ara h2 based on gold nanoparticles-modified self-assembled monolayers in food matrices. Microchemical Journal 2025;219:116140. https://doi.org/10.1016/j.microc.2025.116140 0026-265X 10.1016/j.microc.2025.116140 https://hdl.handle.net/20.500.14352/134717 https://doi.org/10.1016/j.microc.2025.116140 Label-free electrochemical DNA biosensor for detection of peanut allergen Ara h2 based on gold nanoparticles-modified self-assembled monolayers in food matrices