Gomes, Liliana J.Carrilho, João P.Pereira, Pedro M.Moro, Artur J.2023-06-292023-06-292023-01-011424-8220PURE: 64805189PURE UUID: 45228e2f-79cd-4fbb-9e32-5d6535cb86f9Scopus: 85145972805WOS: 000911137700001PubMed: 36617069PubMedCentral: PMC9823994http://hdl.handle.net/10362/154610P.M.P acknowledges funding by: (1) a La Caixa Junior Leader Fellowship (LCF/BQ/PI20/11760012) financed by “la Caixa” Foundation (ID 100010434); Project LISBOA-01-0145-FEDER-007660 Microbiologia Molecular, Estrutural e Celular (ITQB-NOVA); LS4FUTURE—Associated Laboratory (LA/P/0087/2020). Publisher Copyright: © 2023 by the authors.A new Near InfraRed (NIR) fluorescent chemosensor for metal ions and anions is herein presented. The fluorophore is based on a styrylflavylium dye, a synthetic analogue of the natural anthocyanin family, with a di-(2-picolyl)amine (DPA) moiety as the metal chelating unit. The substitution pattern of the styrylflavylium core (with tertiary amines on positions 7 and 4′) shifts the optical properties of the dye towards the NIR region of the electronic spectra, due to a strong push-pull character over the π-conjugated system. The NIR chemosensor is highly sensitive to the presence of Zn2+, which induces a strong CHelation Enhanced Fluorescence (CHEF) effect upon binding to the DPA unit (2.7 fold increase). The strongest competing ion is Cu2+, with a complete fluorescence quenching, while other metals induce lower responses on the optical properties of the chemosensor. Subsequent anion screening of the Zn2+-chemosensor coordination compound has demonstrated a distinct selectivity towards adenosine 5′-triphosphate (ATP) and adenosine 5′-diphosphate (ADP), with high association constants (K ~ 106 M−1) and a strong CHEF effect (2.4 and 2.9 fold fluorescence increase for ATP and ADP, respectively). Intracellular studies with the Zn2+-complexed sensor showed strong luminescence in the cellular membrane of Gram– bacteria (E. coli) and mitochondrial membrane of mammalian cells (A659), which highlights its possible application for intracellular labelling.134308333engadenosine 5′-triphosphate detectiondi-(2-picolyl)amineNear InfraRed fluorescent sensorstyrylflavyliumzinc bindingAnalytical ChemistryInformation SystemsBiochemistryAtomic and Molecular Physics, and OpticsInstrumentationElectrical and Electronic Engineeringjournal article10.3390/s23010471https://www.scopus.com/pages/publications/85145972805