Dual effect of aminobutyric acid group and “molecular wire effect” of conjugated polymer enables ultra-trace detection of Cr 2 O 7 2− in fruits

Food health and safety has always been the top priority of the people’s concern. Accurate and convenient methods for rapid detection of Cr(VI), an internationally recognized carcinogenic heavy metal ion, are becoming more and more important and meaningful in crops. In this work, we proposed a molecular design strategy to explore highly selective and sensitive Cr 2 O 7 2− fluorescent sensors. Fluorescent conjugated polymer ( P(Fmoc-GABA-OH)) had been prepared via electrochemical polymerization. Dual effect of aminobutyric acid group and “molecular wire effect” of conjugated polymer enables ultra-trace detection of Cr 2 O 7 2− and the limit of detection was 16.6 fM. This approach could be applied for monitoring the Cr 2 O 7 2− concentrations in farmland water, soil, tangerine, orange, and grapefruit samples. The present finding will not only extend the scope of conjugated polymers-based sensors but also provide a new strategy for the ultra-trace detection of Cr 2 O 7 2−.