{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T04:53:32Z","timestamp":1777006412649,"version":"3.51.4"},"reference-count":52,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T00:00:00Z","timestamp":1776124800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>In the European Union, mandatory labeling of food and feed products is required when authorized genetically modified organisms (GMOs) exceed 0.9% per ingredient, necessitating reliable analytical methods for official control laboratories. Event-specific PCR assays validated according to ISO\/IEC 17025 are the reference approach for GMO detection, identification, and quantification. The growing use of digital PCR (dPCR) has encouraged the adaptation of real-time PCR methods to dPCR-based strategies, as dPCR enables absolute quantification without calibration standards, shows reduced sensitivity to inhibitors, and allows for the design of a multiplex assay. In this study, an in-house validation of a duplex dPCR assay targeting the maize GM event NK603 and the HMG reference gene was performed on three platforms: Bio-Rad QX200\u2122 (Pleasanton, CA, USA), Qiagen QIAcuity (Venlo, The Netherlands), and Thermo Fisher QuantStudio Absolute Q (Waltham, MA, USA). All validation parameters met the Joint Research Centre (JRC) acceptance criteria. In particular, this assay demonstrated high specificity, sensitivity (limit of quantification or LOQ &lt; 35 copies per reaction), precision, and trueness (RSDr and bias &lt;25%). The data indicate that the duplex dPCR assay can be used for routine GMO analysis and future collaborative validation studies.<\/jats:p>","DOI":"10.3390\/foods15081366","type":"journal-article","created":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T15:47:02Z","timestamp":1776181622000},"page":"1366","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Validation of a Duplex Digital PCR Assay for the Quantification of the NK603 Maize Event Across Three dPCR Platforms"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9247-7073","authenticated-orcid":false,"given":"Daniela","family":"Verginelli","sequence":"first","affiliation":[{"name":"National Reference Laboratory for GM Food and Feed, GMO Unit, Istituto Zooprofilattico Sperimentale del Lazio e della Toscana \u201cMariano Aleandri\u201d, 00178 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3839-7974","authenticated-orcid":false,"given":"Katia","family":"Spinella","sequence":"additional","affiliation":[{"name":"National Reference Laboratory for GM Food and Feed, GMO Unit, Istituto Zooprofilattico Sperimentale del Lazio e della Toscana \u201cMariano Aleandri\u201d, 00178 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sara","family":"Ciuffa","sequence":"additional","affiliation":[{"name":"National Reference Laboratory for GM Food and Feed, GMO Unit, Istituto Zooprofilattico Sperimentale del Lazio e della Toscana \u201cMariano Aleandri\u201d, 00178 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Raffaele","family":"Carrano","sequence":"additional","affiliation":[{"name":"National Reference Laboratory for GM Food and Feed, GMO Unit, Istituto Zooprofilattico Sperimentale del Lazio e della Toscana \u201cMariano Aleandri\u201d, 00178 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9456-359X","authenticated-orcid":false,"given":"Davide","family":"La Rocca","sequence":"additional","affiliation":[{"name":"National Reference Laboratory for GM Food and Feed, GMO Unit, Istituto Zooprofilattico Sperimentale del Lazio e della Toscana \u201cMariano Aleandri\u201d, 00178 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3488-5743","authenticated-orcid":false,"given":"Elisa","family":"Pierboni","sequence":"additional","affiliation":[{"name":"Istituto Zooprofilattico Sperimentale dell\u2019Umbria e delle Marche \u201cTogo Rosati\u201d, 06126 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6337-5999","authenticated-orcid":false,"given":"Monica","family":"Borghi","sequence":"additional","affiliation":[{"name":"Istituto Zooprofilattico Sperimentale dell\u2019Umbria e delle Marche \u201cTogo Rosati\u201d, 06126 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Silvana","family":"Farneti","sequence":"additional","affiliation":[{"name":"Istituto Zooprofilattico Sperimentale dell\u2019Umbria e delle Marche \u201cTogo Rosati\u201d, 06126 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7789-241X","authenticated-orcid":false,"given":"Ugo","family":"Marchesi","sequence":"additional","affiliation":[{"name":"National Reference Laboratory for GM Food and Feed, GMO Unit, Istituto Zooprofilattico Sperimentale del Lazio e della Toscana \u201cMariano Aleandri\u201d, 00178 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,14]]},"reference":[{"key":"ref_1","unstructured":"(2025, April 04). 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