Functionalization of conjugated polymer nanoparticles for fluorescence photomodulation
Christian F Chamberlayne1, Elena A Lepekhina, Brooklynd D Saar
1Department of Chemistry, The College of William and Mary , Williamsburg, Virginia 23187-8795, United States.
Langmuir : the ACS Journal of Surfaces and Colloids
|November 19, 2014
Summary
Dye-doped conjugated polymer nanoparticles (CPNs) offer efficient fluorescence quenching for short-term use. Covalently functionalized CPNs provide better dye stability for long-term applications.
Area of Science:
- Materials Science
- Nanotechnology
- Photophysics
Background:
- Conjugated polymer nanoparticles (CPNs) are functionalized with dyes for tailored applications, often utilizing fluorescence resonance energy transfer (FRET).
- Various methods exist for dye functionalization, including noncovalent doping and covalent attachment.
Purpose of the Study:
- To establish guidelines for selecting appropriate dye functionalization methods for CPNs.
- To compare noncovalent doping versus covalent attachment strategies for CPNs functionalized with photochromic spirooxazines.
Main Methods:
- Four functionalization methods were employed: simple doping, amphiphilic polymer doping, pre-CPN formation covalent functionalization, and post-CPN formation covalent functionalization.
- Evaluation of CPNs focused on fluorescence photomodulation properties to assess CPN-dye photophysical interactions.
- Aging studies were conducted to determine the long-term stability of the functionalized dyes.
Main Results:
- Noncovalent doping resulted in more efficient quenching of CPN emission due to shorter donor-acceptor distances.
- Doped CPNs exhibited significantly greater degradation of photochromic dyes over time compared to covalently functionalized CPNs.
- Covalent functionalization ensured superior dye stability during extended experimental periods.
Conclusions:
- Dye-doped CPNs are suitable for short-term experiments requiring high FRET efficiency.
- Covalent dye functionalization is the preferred method for long-term experiments demanding dye stability.
