Highly sensitive dual-mode fluorescence detection of lead ion in water using aggregation-induced emissive polymers.

A series of fluorene-based conjugated polymers containing the aggregation-induced emissive (AIE)-active tetraphenylethene and dicarboxylate pseudocrown as a receptor exhibits a unique dual-mode sensing ability for selective detection of lead ion in water. Fluorescence turn-off and turn-on detections are realized in 80%-90% and 20% water in tetrahydrofuran (THF), respectively, for lead ion with a concentration as low as 10(-8) m.

Direct detection of ultralow trace amounts of isocyanates in air using a fluorescent conjugated polymer.

A fluorescence sensory polymer containing the pentiptycene and tetraphenylethylene units linked by acetylene was synthesized for direct detection of isocyanates in air. Eight industrially available aliphatic and aromatic isocyanates were tested. The polymer film shows a rapid fluorescence quenching response to any type of isocyanates with a ppt level of detection limit, which is much lower than the permissible exposure limit of 5 ppb.