{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:50:52Z","timestamp":1760147452512,"version":"build-2065373602"},"reference-count":47,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,2,3]],"date-time":"2023-02-03T00:00:00Z","timestamp":1675382400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A novel 3 \u00d7 4 colorimetric sensing platform, named the chemometric-assisted litmus test (CLT), has been developed by covalently anchoring commercial pH indicators to ethylene vinyl alcohol (EVOH). The proposed device can be exploited for pH determinations in a wide range from 1 to 13 and in specific narrow ranges, achieving sufficient accuracy and errors below 0.5 pH units. The experimental procedure is simple, quick and reliable; equilibration is reached in less than 2 h, CLT pictures are acquired by a camera, and data treatment is performed applying chemometric techniques such as principal component analysis (PCA) and partial least square regression (PLS) to RGB indices.<\/jats:p>","DOI":"10.3390\/s23031696","type":"journal-article","created":{"date-parts":[[2023,2,3]],"date-time":"2023-02-03T04:21:43Z","timestamp":1675398103000},"page":"1696","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Chemometric-Assisted Litmus Test: One Single Sensing Platform Adapted from 1\u201313 to Narrow pH Ranges"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4484-4788","authenticated-orcid":false,"given":"Lisa Rita","family":"Magnaghi","sequence":"first","affiliation":[{"name":"Department of Chemistry, University of Pavia, Via Taramelli 12, 27100 Pavia, Italy"},{"name":"Unit\u00e0 di Ricerca di Pavia, INSTM, Via G. 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