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Differences in heterocycle basicity distinguish homocysteine from cysteine using aldehyde-bearing fluorophores.

ABSTRACT: We report the detection of homocysteine over cysteine based upon characteristic differences between 5- and 6-membered heterocyclic amines formed upon reaction with aldehyde-bearing compounds. Homocysteine-derived thiazinane-4-carboxylic acids are more basic than cysteine-derived thiazolidines-4-carboxylic acids. Fluorescence enhancement in response to homocysteine is achieved by tuning pH and excitation wavelength.

SUBMITTER: Barve A

PROVIDER: S-EPMC4116490 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Differences in heterocycle basicity distinguish homocysteine from cysteine using aldehyde-bearing fluorophores.

Barve Aabha A Lowry Mark M Escobedo Jorge O JO Huynh Katherine T KT Hakuna Lovemore L Strongin Robert M RM

Chemical communications (Cambridge, England) 20140801 60

We report the detection of homocysteine over cysteine based upon characteristic differences between 5- and 6-membered heterocyclic amines formed upon reaction with aldehyde-bearing compounds. Homocysteine-derived thiazinane-4-carboxylic acids are more basic than cysteine-derived thiazolidines-4-carboxylic acids. Fluorescence enhancement in response to homocysteine is achieved by tuning pH and excitation wavelength. ...[more]

PMID: 24930401

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