{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T18:02:38Z","timestamp":1770228158448,"version":"3.49.0"},"reference-count":43,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,11]],"date-time":"2023-02-11T00:00:00Z","timestamp":1676073600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea (NRF)","doi-asserted-by":"publisher","award":["NRF-2020R1A2B5B01002392"],"award-info":[{"award-number":["NRF-2020R1A2B5B01002392"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>For surveilling human health, industries, and the environment, pH monitoring is important. Numerous studies on fluorescent probes have been conducted to monitor various pH ranges. However, fluorescent probes that are capable of sensing alkaline regions are rare. In this study, we propose turn-on-type fluorescent probes for detecting alkaline pHs using bis[2-(2\u2032-hydroxyphenyl)benzazole] (bis(HBX)) derivatives. These probes have high pKa values (from 9.7 to 10.8) and exhibit strong fluorescence intensity and color changes at alkaline pHs. Probes derived from bis(HBX) exhibit good photostability, reversibility, and anti-interference toward pH variations, which can be identified as a certain fluorescence change toward a basic pH. Therefore, compounds would be advantageous to use fluorescent probes for monitoring alkaline pH changes.<\/jats:p>","DOI":"10.3390\/s23042044","type":"journal-article","created":{"date-parts":[[2023,2,13]],"date-time":"2023-02-13T02:14:11Z","timestamp":1676254451000},"page":"2044","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Turn-On Fluorescent pH Probes for Monitoring Alkaline pHs Using Bis[2-(2\u2032-hydroxyphenyl)benzazole] Derivatives"],"prefix":"10.3390","volume":"23","author":[{"given":"Hyuna","family":"Lee","sequence":"first","affiliation":[{"name":"Department of Chemistry, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea"}]},{"given":"Suji","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9588-6980","authenticated-orcid":false,"given":"Min Su","family":"Han","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"117506","DOI":"10.1016\/j.saa.2019.117506","article-title":"Fluorescent probes based on benzothiazole-spiropyran derivatives for pH monitoring in vitro and in vivo","volume":"225","author":"Zhu","year":"2020","journal-title":"Spectroc. 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