Amino Acid-Functionalized Polyfluorenes: A Class of Ultra-Sensitive Fluorescent Sensors Favoring Cr₂O₇²⁻ 

Abstract

Conjugated polymers (CPs) are an intriguing material with which to build fluorescent Cr2O72− sensors with excellent sensitivity, but they often lack specific recognition groups. In this study, several typical amino acids with N and O atom-identifying groups were incorporated into fluorene, and then six polyfluorene derivatives were synthesized using electrochemical polymerization. Compared to other cations and anions, all of these amino acid-functionalized polyfluorenes have good selectivity towards Cr2O72− and enable ultra-trace responses with detection thresholds at pM or even fM level.

Keywords

• Cr₂O₇²⁻
• conjugated polymer
• polyfluorene
• amino acid
• fluorescent sensor