{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T14:43:25Z","timestamp":1776437005594,"version":"3.51.2"},"reference-count":55,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,1,17]],"date-time":"2023-01-17T00:00:00Z","timestamp":1673913600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2019s Horizon 2020 research and innovation program","award":["ALT20-03-0247-FEDER-017659 BRO.CQ"],"award-info":[{"award-number":["ALT20-03-0247-FEDER-017659 BRO.CQ"]}]},{"name":"European Union\u2019s Horizon 2020 research and innovation program","award":["UIDB\/04683\/2020"],"award-info":[{"award-number":["UIDB\/04683\/2020"]}]},{"name":"European Union\u2019s Horizon 2020 research and innovation program","award":["UIDP\/04683\/2020"],"award-info":[{"award-number":["UIDP\/04683\/2020"]}]},{"name":"European Union\u2019s Horizon 2020 research and innovation program","award":["PTDC\/CTAMET\/29678\/2017"],"award-info":[{"award-number":["PTDC\/CTAMET\/29678\/2017"]}]},{"name":"ICT project","award":["ALT20-03-0247-FEDER-017659 BRO.CQ"],"award-info":[{"award-number":["ALT20-03-0247-FEDER-017659 BRO.CQ"]}]},{"name":"ICT project","award":["UIDB\/04683\/2020"],"award-info":[{"award-number":["UIDB\/04683\/2020"]}]},{"name":"ICT project","award":["UIDP\/04683\/2020"],"award-info":[{"award-number":["UIDP\/04683\/2020"]}]},{"name":"ICT project","award":["PTDC\/CTAMET\/29678\/2017"],"award-info":[{"award-number":["PTDC\/CTAMET\/29678\/2017"]}]},{"name":"TOMAQAPA project","award":["ALT20-03-0247-FEDER-017659 BRO.CQ"],"award-info":[{"award-number":["ALT20-03-0247-FEDER-017659 BRO.CQ"]}]},{"name":"TOMAQAPA project","award":["UIDB\/04683\/2020"],"award-info":[{"award-number":["UIDB\/04683\/2020"]}]},{"name":"TOMAQAPA project","award":["UIDP\/04683\/2020"],"award-info":[{"award-number":["UIDP\/04683\/2020"]}]},{"name":"TOMAQAPA project","award":["PTDC\/CTAMET\/29678\/2017"],"award-info":[{"award-number":["PTDC\/CTAMET\/29678\/2017"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this work, a newly developed self-contained, portable, and compact iron measurement system (IMS) based on spectroscopy absorption for determination of Fe2+ in water is presented. One of the main goals of the IMS is to operate the device in the field as opposed to instruments commonly used exclusively in the laboratory. In addition, the system has been tuned to quantify iron concentrations in accordance with the values proposed by the regulations for human consumption. The instrument uses the phenanthroline standard method for iron determination in water samples. This device is equipped with an optical sensing system consisting of a light-emitting diode paired with a photodiode to measure absorption radiation through ferroin complex medium. To assess the sensor response, four series of Fe2+ standard samples were prepared with different iron concentrations in various water matrices. Furthermore, a new solid reagent prepared in-house was investigated, which is intended as a \u201cready-to-use\u201d sample pre-treatment that optimizes work in the field. The IMS showed better analytical performance compared with the state-of-the-art instrument. The sensitivity of the instrument was found to be 2.5 \u00b5g Fe2+\/L for the measurement range established by the regulations. The linear response of the photodiode was determined for concentrations between 25 and 1000 \u00b5g Fe2+\/L, making this device suitable for assessing iron in water bodies.<\/jats:p>","DOI":"10.3390\/s23031058","type":"journal-article","created":{"date-parts":[[2023,1,17]],"date-time":"2023-01-17T04:28:47Z","timestamp":1673929727000},"page":"1058","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A Portable Measurement Device Based on Phenanthroline Complex for Iron Determination in Water"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3537-9271","authenticated-orcid":false,"given":"Samuel","family":"Fernandes","sequence":"first","affiliation":[{"name":"Department of Mechatronics Engineering, School of Science and Technology, Universidade de \u00c9vora, 7000-671 \u00c9vora, Portugal"},{"name":"Instrumentation and Control Laboratory (ICL), Insititute of Earth Sciences (ICT), Universidade de \u00c9vora, 7000-671 \u00c9vora, Portugal"}]},{"given":"Mouhaydine","family":"Tlem\u00e7ani","sequence":"additional","affiliation":[{"name":"Department of Mechatronics Engineering, School of Science and Technology, Universidade de \u00c9vora, 7000-671 \u00c9vora, Portugal"},{"name":"Instrumentation and Control Laboratory (ICL), Insititute of Earth Sciences (ICT), Universidade de \u00c9vora, 7000-671 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2334-4055","authenticated-orcid":false,"given":"Daniele","family":"Bortoli","sequence":"additional","affiliation":[{"name":"Instrumentation and Control Laboratory (ICL), Insititute of Earth Sciences (ICT), Universidade de \u00c9vora, 7000-671 \u00c9vora, Portugal"},{"name":"Physics Department, School of Science and Technology (ECT), Universidade de \u00c9vora, 7000-671 \u00c9vora, Portugal"},{"name":"Earth Remote Sensing Laboratory (EaRSLab), Institute of Earth Sciences (ICT), Universidade de \u00c9vora, 7000-671 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3147-4511","authenticated-orcid":false,"given":"Manuel","family":"Feliciano","sequence":"additional","affiliation":[{"name":"Centro de Investiga\u00e7\u00e3o de Montanha (CIMO), Instituto Polit\u00e9cnico de Bragan\u00e7a, Campus de Santa Apol\u00f3nia, 5300-253 Bragan\u00e7a, Portugal"},{"name":"Laborat\u00f3rio Associado para a Sustentabilidade e Tecnologia em Regi\u00f5es de Montanha (SusTEC), Instituto Polit\u00e9cnico de Bragan\u00e7a, Campus de Santa Apol\u00f3nia, 5300-253 Bragan\u00e7a, Portugal"}]},{"given":"Maria Elmina","family":"Lopes","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, School of Science and Technology (ECT), Universidade de \u00c9vora, 7000-671 Evora, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Yaqoob, A., Parveen, T., Umar, K., and Ibrahim, M. 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