Reaction-based AIEE-active conjugated polymer as fluorescent turn on probe for mercury ions with good sensing performance

Based on Hg2+-promoted deprotection reaction of thioketal, a type of thioketal decorated conjugated polymer (PTS) with the feature of aggregation induced emission enhancement (AIEE) was successfully synthesized as fluorescent turn on probe for Hg2+. With the introduction of trace aqueous Hg2+, fluorescence of PTS in THF-H2O mixture (water fraction of 98%) exhibited significant enhancement. The response was very fast with good selectivity towards Hg2+ due to the specific chemical reaction. Other common metal ions (Ag+, Cr3+, Al3+, Fe3+, Ca2+, Ni2+, Co2+, Pb2+, Cu2+, Zn2+, Mg2+, Fe2+, Mn2+, Cd2+, Ba2+, Li+, Na+ and K+) gave nearly no disturbance to the sensing process. Furthermore, the detection limit of Hg2+ reached 2.3 × 10−7 mol L−1 for this sensing system.