{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T09:51:35Z","timestamp":1786960295192,"version":"build-2736575974"},"reference-count":36,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2024,7,5]],"date-time":"2024-07-05T00:00:00Z","timestamp":1720137600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001602","name":"Science Foundation Ireland","doi-asserted-by":"publisher","award":["12\/RC\/2275\/P2 12\/RI\/2346\/SOF 16\/RI\/3399"],"award-info":[{"award-number":["12\/RC\/2275\/P2 12\/RI\/2346\/SOF 16\/RI\/3399"]}],"id":[{"id":"10.13039\/501100001602","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Chem."],"abstract":"<jats:p>The development of selective and sensitive probes for monitoring caspase-3 activity\u2013a critical enzyme involved in apoptosis\u2013remains an area of significant interest in biomedical research. Herein, we report the synthesis and characterisation of a novel ratiometric fluorescent probe, Ac-DEVD-PABC-Naph, designed to detect caspase-3 activity. The probe utilises a 1,8-naphthalimide fluorophore covalently linked to a peptide sequence via a self-immolative <jats:italic>p<\/jats:italic>-aminobenzyl alcohol (PABA) linker. Upon enzymatic cleavage by caspase-3, the probe undergoes spontaneous degradation, releasing the free naphthalimide fluorophore, resulting in a ratiometric change in fluorescence emission. Spectroscopic studies revealed a time-dependent ratiometric fluorescent response, demonstrating the probe\u2019s ability to visualise caspase-3 activity with high sensitivity. Enzyme kinetics such as <jats:italic>K<\/jats:italic><jats:sub><jats:italic>m<\/jats:italic><\/jats:sub> (Michaelis constant), <jats:italic>k<\/jats:italic><jats:sub><jats:italic>cat<\/jats:italic><\/jats:sub> (turnover number), and <jats:italic>LOD<\/jats:italic> (Limit of Detection) were obtained, suggesting that the probe possesses comparable kinetic data to other probes in literature, but with the added benefits of ratiometric detection. Selectivity studies also demonstrated the probe\u2019s specificity for caspase-3 over other endogenous species and enzymes. Ac-DEVD-PABC-Naph may be a promising tool for the quantitative detection and fluorescent visualisation of caspase-3 activity in biological systems, with potential applications in apoptosis research and drug development.<\/jats:p>","DOI":"10.3389\/fchem.2024.1418378","type":"journal-article","created":{"date-parts":[[2024,7,5]],"date-time":"2024-07-05T05:09:46Z","timestamp":1720156186000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":11,"title":["Utilising a 1,8-naphthalimide probe for the ratiometric fluorescent visualisation of caspase-3"],"prefix":"10.3389","volume":"12","author":[{"given":"Conor","family":"Wynne","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert B. 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