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PH-Dependent Fluorescent Probe That Can Be Tuned for Cysteine or Homocysteine.

ABSTRACT: The very close structural similarities between cysteine and homocysteine present a great challenge to achieve their selective detection using regular fluorescent probes, limiting the biological and pathological studies of these two amino thiols. A coumarin-based fluorescent probe was designed featuring pH-promoted distinct turn-on followed by ratiometric fluorescence responses for Cys and turn-on fluorescence response for Hcy through two different reaction paths. These specific responses demonstrate the activity differences between Cys and Hcy qualitatively for the first time. The probe could also be used for Cys and Hcy imaging in living cells.

SUBMITTER: Yue Y

PROVIDER: S-EPMC5570466 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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pH-Dependent Fluorescent Probe That Can Be Tuned for Cysteine or Homocysteine.

Yue Yongkang Y Huo Fangjun F Li Xiaoqi X Wen Ying Y Yi Tao T Salamanca James J Escobedo Jorge O JO Strongin Robert M RM Yin Caixia C

Organic letters 20161220 1

The very close structural similarities between cysteine and homocysteine present a great challenge to achieve their selective detection using regular fluorescent probes, limiting the biological and pathological studies of these two amino thiols. A coumarin-based fluorescent probe was designed featuring pH-promoted distinct turn-on followed by ratiometric fluorescence responses for Cys and turn-on fluorescence response for Hcy through two different reaction paths. These specific responses demonst ...[more]

PMID: 27995792

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