5 years ago

Higher Energy Gap Control of Fluorescence in Conjugated Polymers: Turn-On Amplifying Chemosensor for Hydrogen Sulfide

Higher Energy Gap Control of Fluorescence in Conjugated Polymers: Turn-On Amplifying Chemosensor for Hydrogen Sulfide
Chien-Hung Chiang, Evgueni E. Nesterov, Deepa Pangeni
The significance of conjugated polymers for sensing applications stems from the intrinsic amplification of analyte binding events which is related to the efficient excitation energy migration in the polymers. Within the framework of conventional design of amplifying sensory polymers, interaction with an analyte creates a lower energy gap site within the conjugated backbone which acts as a trap for randomly migrating excitons typically producing a fluorescence quenching effect (turn-off sensors). Herein, we describe an alternative “higher energy gap” paradigm, a general design concept surprisingly overlooked so far. Within this paradigm, reaction with an analyte generates a higher energy gap site in the conjugated backbone. This higher energy gap site diminishes exciton migration length and causes pronounced enhancement of the polymer fluorescence (turn-on response). This effect benefits from the signal amplification and therefore can be used universally to design a wide range of fluorescent sensors. To demonstrate the practical utility of the “higher energy gap” concept, we used it to develop an efficient turn-on amplifying fluorescent sensor for hydrogen sulfide—an important industrial and biomedical analytical target. From a fundamental standpoint, the “higher energy gap” paradigm demonstrates the importance of the through-bond (Dexter-type) mechanism for intramolecular energy transfer in conjugated polymers—still a widely debatable issue.

Publisher URL: http://dx.doi.org/10.1021/acs.macromol.7b01706

DOI: 10.1021/acs.macromol.7b01706

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.