{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T03:47:30Z","timestamp":1785296850240,"version":"3.55.0"},"reference-count":47,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,2,6]],"date-time":"2025-02-06T00:00:00Z","timestamp":1738800000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Science Centre, Poland","award":["2018\/29\/N\/NZ7\/01918"],"award-info":[{"award-number":["2018\/29\/N\/NZ7\/01918"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Fluorescent labeling utilizing Cu(I)-catalyzed azide\u2013alkyne cycloaddition reactions (CuAAC) is among the leading applications of the \u201cclick\u201d chemistry strategy. Fluorescent probes for this approach can be constructed by linking an azide or alkyne group to a fluorophore, such as the recently developed Safirinium derivatives. These compounds are water-soluble, highly fluorescent heterocycles based on 1,2,4-triazolium, with significant potential for various labeling applications, although they have not yet been converted to azide or alkyne probes. Herein, we report the synthesis of Safirinium-based azide and alkyne functionalized molecular probes for \u201cclick\u201d chemistry labeling. We also describe their CuAAC reactions with model compounds, including a lipid mimetic long-chain azide, an azido sugar derivative, and azidothymidine, as well as two model alkynes. We demonstrate that the Safirinium-based probes and their derivatives are chemically stable, suitable for fluorescent microscopy observations, and safe to use. Most of these probes show no toxic effects on CHO-K1 and NIH-3T3 cells.<\/jats:p>","DOI":"10.3390\/molecules30030731","type":"journal-article","created":{"date-parts":[[2025,2,6]],"date-time":"2025-02-06T08:53:41Z","timestamp":1738832021000},"page":"731","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Safirinium Fluorescent \u201cClick\u201d Molecular Probes: Synthesis, CuAAC Reactions, and Microscopic Imaging"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2292-594X","authenticated-orcid":false,"given":"Patryk","family":"Kasza","sequence":"first","affiliation":[{"name":"Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Krak\u00f3w, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7014-809X","authenticated-orcid":false,"given":"Przemys\u0142aw W.","family":"Szafra\u0144ski","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Krak\u00f3w, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7524-9909","authenticated-orcid":false,"given":"Joanna","family":"Fedorowicz","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Medical University of Gda\u0144sk, Al. Gen. J. Hallera 107, 80-416 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Faustyna","family":"Krzysztofiak","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Krak\u00f3w, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1186-3085","authenticated-orcid":false,"given":"Krzysztof","family":"Pociecha","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Krak\u00f3w, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2477-5607","authenticated-orcid":false,"given":"Katarzyna","family":"W\u00f3jcik-Pszczo\u0142a","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Krak\u00f3w, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2939-224X","authenticated-orcid":false,"given":"Paulina","family":"Koczurkiewicz-Adamczyk","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Krak\u00f3w, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7304-6881","authenticated-orcid":false,"given":"Mariusz","family":"K\u0119pczynski","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Krak\u00f3w, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2966-7645","authenticated-orcid":false,"given":"Jaros\u0142aw","family":"S\u0105czewski","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Medical University of Gda\u0144sk, Al. Gen. J. Hallera 107, 80-416 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6192-8721","authenticated-orcid":false,"given":"Pawe\u0142","family":"Zajdel","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Krak\u00f3w, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marek","family":"Ceg\u0142a","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Krak\u00f3w, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"206","DOI":"10.1016\/j.chroma.2014.06.017","article-title":"Fluorescence Derivatization Method for Sensitive Chromatographic Determination of Zidovudine Based on the Huisgen Reaction","volume":"1355","author":"Maeda","year":"2014","journal-title":"J. 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