A fluorescent sensor based on quinazoline ketone derivatives for selectivity of Fe³⁺

Abstract

In this work, we provided a fluorescent sensor based on a compound containing fluorophore quinazoline ketone for detecting metal ions. 2-Methyl-4(3 H)-quinazoline thione was synthesised as a fluorescent probe for tervalent ferric ion (Fe³⁺) detection. Fluorescent determination of 2-methyl-4(3 H)-quinazoline thione indicated its maximum emission wavelength of 306.5 nm. The fluorescence interference and titration experiments have shown that the compound has a high selective fluorescence response to Fe³⁺. With an increase in the Fe³⁺ ion concentration, the fluorescence emission strength gradually weakened, and a slight red shift appeared. With Job’s method, 2-methyl-4(3 H)-quinazoline thione was proved to form a 1:2 complex with Fe³⁺. The results revealed that 2-methyl-4(3 H)-quinazoline thione could be used as a fluorescent probe for the recognition of Fe³⁺ with high selectivity.

Keywords:

• fluorescent sensor
• quinazoline ketone
• 2-methyl-4(3H)-quinazoline thione
• emission wavelength
• fluorescence emission strength

Acknowledgement

We thank the fruitful inputs of the anonymous referees.

Additional information

Funding

This work was supported by Jiangsu Students’ Platform for the Innovation and Entrepreneurship Training Program [grant number 201413905006Y]; the General Program of the National Natural Science Foundation of China [grant number 51003047]; the Natural Science Foundation of Jiangsu Province [grant number 55129003] and Higher Education Institutions Natural Science Foundation of Jiangsu Educational Commission [grant number 09KJB540001], [grant number 10KJB540001].