Immunorecognition magnetic supports for the development of an electrochemical immunoassay for azaspiracid detection in mussels ; DOI: 10.1016/j.bios.2017.02.015 URL: http://www.sciencedirect.com/science/article/pii/S0956566317301021 Filiació URV: SI Memòria ; As azaspiracids (AZAs) are being reported from the coastal waters of an increasing number of countries on a global scale, the need for rapid, simple and cost-effective methods to detect these marine toxins and protect seafood consumers’ health is becoming evident. A magnetic bead (MB)-based direct immunoassay for the detection of AZAs, using protein G-coated MBs as supports for antibody immobilisation and peroxidase-labelled AZA as a tracer is detailed. A colorimetric approach was first developed to optimise the experimental parameters and establish the cross-reactivity factors for AZA-1–10. The subsequent combination of the immunorecognition MBs with 8-electrode arrays enabled the multiplexed electrochemical detection of AZAs. Naturally-contaminated mussel samples were analysed and the results obtained showed an excellent correlation with LC-MS/MS analysis. The MB-based immunoassay facilitated the quantification of a wide range of AZA concentrations (120–2875 μg AZA-1 equiv./kg), with a limit of detection (63 μg AZA-1 equiv./kg) below the European regulatory threshold, using a protocol that requires very few steps and a short analysis time (~ 15 min). The simplicity, cost-effectiveness, rapidity, robustness, selectivity and precision of the assay provide a valuable tool for the detection of all regulated AZAs and other toxic AZA analogues, suitable for end users in the field of food safety.