Fluorescence probe with a pH-sensitive trigger.

Amit K Galande; Ralph Weissleder; Ching-Hsuan Tung

doi:10.1021/bc050330e

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Fluorescence probe with a pH-sensitive trigger.

Amit K Galande·Ralph Weissleder·Ching-Hsuan Tung

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Abstract

Acid-catalyzed hydrolysis was used as the mechanism to design a new type of environmentally sensitive fluorescence probe. A mild and selective periodate oxidation of the 2-amino alcohol of serine in the presence of a disulfide bond was developed to prepare dialdehyde peptides. Two identical fluorochrome hydrazide derivatives were then linked to the dialdehyde peptide forming an acid-labile hydrazone linkage. This self-quenched probe is weakly fluorescent at a physiological pH of 7.4 but shows more than 3-fold fluorescence enhancement at pH 4.5.

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Amino Acid Sequence Carbocyanines Fluorescent Dyes Hydrogen-Ion Concentration Molecular Structure Oligopeptides Peptides Journal Article Research Support, N.I.H., Extramural

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Amit K Galande, Ralph Weissleder, Ching-Hsuan Tung. Fluorescence probe with a pH-sensitive trigger.. https://doi.org/10.1021/bc050330e

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