Spermidine induced aggregation of terphenyl derivative: An efficient probe for detection of spermidine in living cells

A terphenyl derivative 3 has been designed and synthesized which undergoes self-assembly in mixed aqueous media to form weakly emissive aggregates. Aggregates of derivative 3 selectively detect spermidine and exhibit spermidine-induced emission enhancement. The interactions between aggregates of derivative 3 and spermidine result in the formation of AIE- active Schiff base adduct 4. In principle, the formation of Schiff base adduct 4 through the reaction of aldehyde groups present on aggregates of probe 3 and amino groups on spermidine determines the selective recognition of spermidine over other amines examined. The detection limit of probe 3 for spermidine was found to be 46 nM. Additionally, the utility of probe 3 for detection of spermidine in artificial urine sample and imaging of live HeLa cells has been demonstrated.