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They contaminate drinking water, bioaccumulate in aquatic organisms, and pose serious health risks. Conventional detection methods, though reliable, are costly, time-consuming, and require specialized personnel, limiting rapid or on-site use. Biosensors have emerged as attractive alternatives, with electrochemical platforms standing out for their high sensitivity, low cost, miniaturization potential, and easy integration into portable devices. These advantages make them promising tools for in situ monitoring of saxitoxins and justify a dedicated review. This work critically analyzes electrochemical biosensors for STX detection, highlighting advances, limitations, and challenges toward commercialization. We discuss operating principles, recognition elements, analytical performance, and classify devices by electrochemical technique (potentiometric, impedimetric, voltammetric), providing a comparative perspective on their respective strengths and limitations. Despite remarkable sensitivity\u2014often below regulatory limits\u2014key obstacles remain: lack of fabrication standardization, poor long-term stability, limited validation with naturally contaminated samples, insufficient robustness for complex matrices, low reproducibility, and absence of regulatory approval pathways. In addition, challenges associated with fabrication scalability and interlaboratory reproducibility continue to hinder the transition from proof-of-concept devices to commercially viable technologies. Overcoming these barriers is crucial for translating laboratory prototypes into reliable, field-deployable devices for environmental monitoring and food safety applications. Future developments should focus on improving robustness, reproducibility, and analytical validation to accelerate the practical implementation of electrochemical STX biosensors.<\/jats:p>","DOI":"10.1007\/s10661-026-15797-x","type":"journal-article","created":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T21:30:07Z","timestamp":1787088607000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Electrochemical biosensors for saxitoxin detection: advances, limitations, and challenges for market transition"],"prefix":"10.1007","volume":"198","author":[{"given":"Isadora Bernardes","family":"Sequalini","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thiago Teixeira","family":"da Silva","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Larissa Victoria","family":"do Carmo de Oliveira","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nirton Cristi Silva","family":"Vieira","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,8,18]]},"reference":[{"issue":"4","key":"15797_CR1","doi-asserted-by":"publisher","DOI":"10.3390\/toxins10040141","volume":"10","author":"N Arnich","year":"2018","unstructured":"Arnich, N., & Th\u00e9bault, A. 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This article is a review of previously published studies and does not involve experiments with human participants or animals performed by the authors.","order":2,"name":"Ethics","label":"Ethics approval","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable.","order":3,"name":"Ethics","label":"Human ethics declaration","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable.","order":4,"name":"Ethics","label":"Consent to participate","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable.","order":5,"name":"Ethics","label":"Consent for publication","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare no competing interests.","order":6,"name":"Ethics","label":"Competing interests","group":{"name":"EthicsHeading","label":"Declarations"}}],"article-number":"959"}}