Anthryl-doped conjugated polyelectrolytes as aggregation-based sensors for nonquenching multicationic analytes.
The fluorescence-based detection of nonquenching, multicationic small molecules has been demonstrated using a blue-emitting, polyanionic poly(p-phenylene ethynylene) (PPE) doped with green-emitting exciton traps (anthryl units). Multicationic amines (spermine, spermidine, and neomycin) were found to effectively induce the formation of tightly associated aggregates between the polymer chains in solution. This analyte-induced aggregation, which was accompanied by enhanced exciton migration in the PPE, ultimately led to a visually noticeable blue-to-green fluorescence color change in the solution. The aggregation-based sensor exhibited poor sensitivity toward dicationic and monocationic amines, demonstrating that a conjugated polyelectrolyte sensor relying on nonspecific, electrostatic interactions may still attain a certain level of selectivity.
Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Andrew
A
Satrijo
Timothy M
TM
Swager
D002412:Cations; D004573:Electrolytes / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D055672:Static Electricity
D002412:Cations; D004573:Electrolytes