Journal
TALANTA
Volume 83, Issue 5, Pages 1695-1700Publisher
ELSEVIER
DOI: 10.1016/j.talanta.2010.11.072
Keywords
Hetarylazo; Colorimetric; Sensor; Copper ions; Internal charge-transfer
Categories
Funding
- CSIR, New Delhi [01(2265)/08-EMR (II)]
- UGC (SAP), New Delhi
Ask authors/readers for more resources
Although the high sensitivity, high selectivity and fast response make emission (fluorescence) based technique as one of the most promising tool for developing the chemosensors for metal ions, the past few years have witnessed a demand for the absorption based chemosensors for paramagnetic heavy metal ions, especially Cu2+. Being paramagnetic, Cu2+ leads to the low signal outputs (turn-off) caused by decreased emission which may sometimes give false positive response, rendering the emission based technique less reliable for analytical purposes. Herein, we report synthesis and characterization of a hetarylazo derivative, characterized by a strong charge-transfer band which gets attenuated convincingly in the presence of Cu2+ leading to distinct naked-eye color change (yellow to purple), and to a lesser extent in the presence of Cd2+, Zn2+, Co2+, Pb2+, Fe2+, Ni2+, Fe3+ and Hg2+ for which the naked eye sensitivity was comparatively (w.r.t. Cu2+) much less. No response was observed for the other metal ions including Li+, Na+, K+, Mg2+, Ca2+, Ba2+, Mn2+, Ag+, Zn2+, Cd2+, Pb2+, and lanthanides Ce3+, La3+, Pr3+, Eu3+, Nd3+, Lu3+, Yb3+, Tb3+, Sm3+, Gd3+. The proposed sensing mechanism has been ascribed to the stabilization of LUMO after complexation with Cu2+ and a 1:1 stoichiometry has been deduced. (C) 2010 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available