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Title: Fluorogenic atom transfer radical polymerization in aqueous media as a strategy for detection
The development of novel approaches to signal amplification in aqueous media could enable new diagnostic platforms for the detection of water-soluble analytes, including biomolecules. This paper describes a fluorogenic polymerization approach to amplify initiator signal by the detection of visible fluorescence upon polymerization in real-time. Fluorogenic monomers were synthesized and co-polymerized by atom transfer radical polymerization (ATRP) in water to reveal increasing polymer fluorescence as a function of both reaction time and initiator concentration. Optimization of the fluorogenic ATRP reaction conditions allowed for the quantitative detection of a small-molecule initiator as a model analyte over a broad linear concentration range (pM to mM). Raising the reaction temperature from 30 °C to 60 °C facilitated sensitive initiator detection at sub-picomolar concentrations in as little as 1 h of polymerization. This method was then applied to the detection of streptavidin as a model biological analyte by fluorogenic polymerization from a designed biotinylated ATRP initiator. Taken together, these studies represent the first example of a fluorogenic ATRP reaction and establish fluorogenic polymerization as a promising approach for the direct detection of aqueous analytes and biomolecular recognition events.  more » « less
Award ID(s):
1726441
PAR ID:
10105260
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Chemical Science
Volume:
10
Issue:
4
ISSN:
2041-6520
Page Range / eLocation ID:
1017 to 1022
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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