%0 Journal Article
%A Hervás Pérez, Juan Pablo
%A Sánchez-Paniagua López, Marta
%T Label-free electrochemical DNA biosensor for detection of peanut allergen Ara h2 based on gold nanoparticles-modified self-assembled monolayers in food matrices
%D 2025
%@ 0026-265X
%U https://hdl.handle.net/20.500.14352/134717
%X 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.
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