{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,1]],"date-time":"2026-03-01T05:31:23Z","timestamp":1772343083956,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2016,5,2]],"date-time":"2016-05-02T00:00:00Z","timestamp":1462147200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Radiation Fusion Technology Program","award":["2015M2A2A6A02045262"],"award-info":[{"award-number":["2015M2A2A6A02045262"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A simple, rapid, and convenient colorimetric chemosensor of a specific target toward the end user is still required for on-site detection and real-time monitoring applications. In this study, we developed a rapid in situ colorimetric assay for cobalt detection using the naked eye. Interestingly, a yellow to light orange visual color transition was observed within 3 s when a Chrysoidine G (CG) chemosensor was exposed to cobalt. Surprisingly, the CG chemosensor had great selectivity toward cobalt without any interference of other metal ions. Under optimized conditions, a lower detection limit of 0.1 ppm via a spectrophotometer and a visual detection limit of 2 ppm with a linear range from 0.4 to 1 ppm (R2 = 0.97) were determined. Moreover, the CG chemosensor is reversible and maintains its functionality after treatment with chelating agents. In conclusion, we show the superior capabilities of the CG chemosensor, which has the potential to provide extremely facile handling, high sensitivity, and a fast response time for applications of on-site detection to real-time cobalt monitoring for the general public.<\/jats:p>","DOI":"10.3390\/s16050626","type":"journal-article","created":{"date-parts":[[2016,5,2]],"date-time":"2016-05-02T10:17:11Z","timestamp":1462184231000},"page":"626","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["A Rapid In Situ Colorimetric Assay for Cobalt Detection by the Naked Eye"],"prefix":"10.3390","volume":"16","author":[{"given":"Sung-Min","family":"Kang","sequence":"first","affiliation":[{"name":"Biotechnology Research Division, Advanced Radiation Technology Institute (ARTI), Korea Atomic Energy Research Institute (KAERI), 29 Geumgu-gil, Jeongeup, Jeonbuk 56212, Korea"},{"name":"Department of Chemical Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sung-Chan","family":"Jang","sequence":"additional","affiliation":[{"name":"Biotechnology Research Division, Advanced Radiation Technology Institute (ARTI), Korea Atomic Energy Research Institute (KAERI), 29 Geumgu-gil, Jeongeup, Jeonbuk 56212, Korea"},{"name":"Department of Biological Engineering, Biohybrid Systems Research Center (BSRC), Inha University, 100 Inha-ro, Incheon 22212, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gi","family":"Kim","sequence":"additional","affiliation":[{"name":"Biotechnology Research Division, Advanced Radiation Technology Institute (ARTI), Korea Atomic Energy Research Institute (KAERI), 29 Geumgu-gil, Jeongeup, Jeonbuk 56212, Korea"},{"name":"Department of Chemical Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chang-Soo","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1612-4473","authenticated-orcid":false,"given":"Yun","family":"Huh","sequence":"additional","affiliation":[{"name":"Department of Biological Engineering, Biohybrid Systems Research Center (BSRC), Inha University, 100 Inha-ro, Incheon 22212, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Changhyun","family":"Roh","sequence":"additional","affiliation":[{"name":"Biotechnology Research Division, Advanced Radiation Technology Institute (ARTI), Korea Atomic Energy Research Institute (KAERI), 29 Geumgu-gil, Jeongeup, Jeonbuk 56212, Korea"},{"name":"Radiation Biotechnology and Applied Radioisotope Science, University of Science and Technology (UST), 217 Gajeong-ro, Daejeon 34113, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,5,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"143","DOI":"10.1289\/ehp.8140143","article-title":"Role of cobalt, iron, lead, manganese, mercury, platinum, selenium, and titanium in carcinogenesis","volume":"40","author":"Kazantzis","year":"1981","journal-title":"Environ. 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