A novel colorimetric chemosensor based on quinoline for the sequential detection of Fe3+ and PPi in aqueous solution

Abstract

A novel quinoline-functionalized Schiff-base derivative PY was designed and synthesized. Sensor PY displayed highly selective and sensitive fluorescence enhancement and naked-eye color change to Fe3+ in the presence of other competing cations. The mechanisms have been supported by Job’s plot evaluation, FT-MS and theoretical calculations. The in situ generated PY-Fe3+ complex solution exhibited a high selectivity toward PPi via Fe3+ displacement approach. The detection limits of sensor PY to Fe3+ and PY-Fe3+ complex to PPi were estimated to be 4.24×10−8M and 8.18×10−8M, respectively. This successive recognition feature of sensor PY makes it has a potential utility for Fe3+ and PPi detection in aqueous solution. A B3LYP/6-31G(d,p) basis set was employed for optimization of PY and PY-Fe3+ complex.