Various located urea and schiff-base bifunctional derivatives: Their gelation and Zn2+ sensing behaviors

The efficient combination of various moieties is helpful to develop organic functional molecules. Herein, three of urea and Schiff-base bifunctional derivatives (OG, MG and PG) were prepared from o/m/p-diaminobenzene respectively. Benefitting from the urea and Schiff-base, these derivatives revealed satisfactory gelation capacity. However, the various locations of urea and imine paved them markedly different assembly performances during the gel formation. Additionally, these functional molecules displayed obvious off-on fluorescence sensing behaviors towards Zn2+ in solution ascribing to the imine and neighbor phenolic hydroxyl, among which the MG displayed the best Zn2+ selectivity. Crucially, the MG also realized Zn2+ probing at cellular level and its gel gave a visual detection via the gel-sol transition.

Automated summary

The efficient combination of urea and Schiff-base bifunctional derivatives led to satisfactory gelation capacity and fluorescent sensing behaviors towards Zn2+. Among the derivatives, MG exhibited the best Zn2+ selectivity and enabled visual detection at cellular level via gel-sol transition. The assembly performances of these derivatives during gel formation were markedly different due to the various locations of urea and imine moieties.