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Pentamethine sulfobenzoindocyanine dyes with low net charge states and high photostability.

ABSTRACT: A series of Cy5.5 dye analogs and targeted probes with net charges varied from -3 to 0 were synthesized by an optimized method, followed by comparing their spectral and photostability properties in saturated solutions of air, oxygen, and argon. The Cy5.5 analogs with reduced charge were relatively stable when irridated at their excitation maxima, with a trend of higher stability with lower net charge states. The photostability of dyes was markedly lower in pure oxygen and higher in inert argon relative to ambient atmospheric conditions. The stability of c(RGDyK) conjugates as models of targeted molecular imaging agents mirrored these results and demonstrated the practical utility of the new family of Cy5.5 fluorophores.

SUBMITTER: Dobson DE

PROVIDER: S-EPMC6980914 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Pentamethine sulfobenzoindocyanine dyes with low net charge states and high photostability.

Dobson Damien E DE Mahoney Emily R ER Mach Toan P TP LeTourneau Ryan J RJ Schmitthenner Hans F HF

Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology 20200101 1

A series of Cy5.5 dye analogs and targeted probes with net charges varied from -3 to 0 were synthesized by an optimized method, followed by comparing their spectral and photostability properties in saturated solutions of air, oxygen, and argon. The Cy5.5 analogs with reduced charge were relatively stable when irridated at their excitation maxima, with a trend of higher stability with lower net charge states. The photostability of dyes was markedly lower in pure oxygen and higher in inert argon r ...[more]

PMID: 31825058

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