Importance of having low-density functional groups for generating high-performance semiconducting polymer dots
2012 (English)In: ACS Nano, ISSN 1936-0851, Vol. 6, no 6, 5429-5439 p.Article in journal (Refereed) Published
Semiconducting polymers with low-density side-chain carboxylic acid groups were synthesized to form stable, functionalized, and highly fluorescent polymer dots (Pdots). The influence of the molar fraction of hydrophilic side-chains on Pdot properties and performance was systematically investigated. Our results show that the density of side-chain carboxylic acid groups significantly affects Pdot stability, internal structure, fluorescence brightness, and nonspecific binding in cellular labeling. Fluorescence spectroscopy, single-particle imaging, and a dye-doping method were employed to investigate the fluorescence brightness and the internal structure of the Pdots. The results of these experiments indicate that semiconducting polymers with low density of side-chain functional groups can form stable, compact, and highly bright Pdots as compared to those with high density of hydrophilic side-chains. The functionalized polymer dots were conjugated to streptavidin (SA) by carbodiimide-catalyzed coupling and the Pdot-SA probes effectively and specifically labeled the cancer cell-surface marker Her2 in human breast cancer cells. The carboxylate-functionalized polymer could also be covalently modified with small functional molecules to generate Pdot probes for click chemistry-based bio-orthogonal labeling. This study presents a promising approach for further developing functional Pdot probes for biological applications.
Place, publisher, year, edition, pages
American Chemical Society (ACS), 2012. Vol. 6, no 6, 5429-5439 p.
Semiconducting polymer dots, specific cellular targeting
IdentifiersURN: urn:nbn:se:liu:diva-90562DOI: 10.1021/nn301308wOAI: oai:DiVA.org:liu-90562DiVA: diva2:613820