{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T21:12:15Z","timestamp":1778274735015,"version":"3.51.4"},"reference-count":75,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2013,12,5]],"date-time":"2013-12-05T00:00:00Z","timestamp":1386201600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Fluorescent proteins have been extensively used for engineering genetically encoded sensors that can monitor levels of ions, enzyme activities, redox potential, and metabolites. Certain fluorescent proteins possess specific pH-dependent spectroscopic features, and thus can be used as indicators of intracellular pH. Moreover, concatenated pH-sensitive proteins with target proteins pin the pH sensors to a definite location within the cell, compartment, or tissue. This study provides an overview of the continually expanding family of pH-sensitive fluorescent proteins that have become essential tools for studies of pH homeostasis and cell physiology. We describe and discuss the design of intensity-based and ratiometric pH sensors, their spectral properties and pH-dependency, as well as their performance. Finally, we illustrate some examples of the applications of pH sensors targeted at different subcellular compartments.<\/jats:p>","DOI":"10.3390\/s131216736","type":"journal-article","created":{"date-parts":[[2013,12,5]],"date-time":"2013-12-05T11:35:30Z","timestamp":1386243330000},"page":"16736-16758","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":114,"title":["Illumination of the Spatial Order of Intracellular pH by Genetically Encoded pH-Sensitive Sensors"],"prefix":"10.3390","volume":"13","author":[{"given":"Mojca","family":"Ben\u010dina","sequence":"first","affiliation":[{"name":"Laboratory of Biotechnology, National Institute of Chemistry, 1000 Ljubljana, Slovenia"},{"name":"Center of Excellence EN-FIST, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2013,12,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1038\/nrm2820","article-title":"Sensors and regulators of intracellular pH","volume":"11","author":"Casey","year":"2010","journal-title":"Nat. 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