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Ultrabright and Serum-Stable Squaraine Dyes.

ABSTRACT: Highly stable symmetric and asymmetric squaraine fluorophores have been synthesized featuring an internal salt bridge between a quaternary ammonium cation and the central oxycyclobutenolate ring of the chromophore. Some of our newly synthesized symmetric and asymmetric compounds display increased molar absorptivity, quantum yield in serum, and thermal/photochemical stability over previously reported squaraine-based dyes. Consequently, both classes show great promise in resurfacing the normal environment-labile squaraine dyes as novel imaging agents and scaffolds for fluorescence sensing. Furthermore, incorporating a covalent attachment point away from the conjugated system allows for biological tagging applications without disturbing the optimum optical characteristics of the newly designed fluorophore.

SUBMITTER: Yadav Y

PROVIDER: S-EPMC8428814 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Ultrabright and Serum-Stable Squaraine Dyes.

Yadav Yogesh Y Owens Eric E Nomura Shinsuke S Fukuda Takeshi T Baek Yoonji Y Kashiwagi Satoshi S Choi Hak Soo HS Henary Maged M

Journal of medicinal chemistry 20200819 17

Highly stable symmetric and asymmetric squaraine fluorophores have been synthesized featuring an internal salt bridge between a quaternary ammonium cation and the central oxycyclobutenolate ring of the chromophore. Some of our newly synthesized symmetric and asymmetric compounds display increased molar absorptivity, quantum yield in serum, and thermal/photochemical stability over previously reported squaraine-based dyes. Consequently, both classes show great promise in resurfacing the normal env ...[more]

PMID: 32787096

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