Detection of cyanide ions in aqueous solutions using cost effective colorimetric sensor

P Madhusudhana Reddy; Shih-Rong Hsieh; Chi-Jung Chang; Jing-Yuan Kang

doi:10.1016/j.jhazmat.2017.04.001

Detection of cyanide ions in aqueous solutions using cost effective colorimetric sensor

J Hazard Mater. 2017 Jul 15:334:93-103. doi: 10.1016/j.jhazmat.2017.04.001. Epub 2017 Apr 3.

Authors

P Madhusudhana Reddy¹, Shih-Rong Hsieh², Chi-Jung Chang³, Jing-Yuan Kang¹

Affiliations

¹ Department of Chemical Engineering, Feng Chia University, 100, Wenhwa Road, Seatwen, Taichung 40724, Taiwan, ROC.
² Department of Surgery, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Section 4, Taichung 40705, Taiwan, ROC.
³ Department of Chemical Engineering, Feng Chia University, 100, Wenhwa Road, Seatwen, Taichung 40724, Taiwan, ROC. Electronic address: changcj@fcu.edu.tw.

PMID: 28402899
DOI: 10.1016/j.jhazmat.2017.04.001

Abstract

Cyanide (CN̄) is one of the most toxic material to the human and environment. It is very important to develop the diagnostic tools for the detection of CN̄ ions. Moreover, detection of the ions in an aqueous medium is a challenging task as water molecules interfere with the sensing mechanism. In this context, we prepared chemical sensor, S1, having anthraquinone as a signaling unit and thiourea as a binding site. This sensor exhibited distinct visual color and spectral changes in response to CN̄ ion over other testing anions in 50% aq. DMSO solution. However, in 20% aq. DMSO solution, S1 exhibited obvious spectral and color changes in response to CN̄, fluoride (F̄), acetate (Ac̄) and benzoate (Bz̄). Another sensor, S2, having a same signaling unit with that of S1, but a different binding site of urea group. In contrast to S1, S2 exhibited obvious spectral and color changes to F̄ in 2.5% aq. DMSO solution. NMR titration results suggested that the spectral and colorimetric responses were due to the formation of host-guest complex and deprotonation events. Finally, economically viable paper-based colorimetric "test stripes" of S1 were fabricated to detect the CN̄ ions in 100% aqueous solution.

Keywords: Colorimetric; Cyanide; Naked eye; Sensing; Test stripes.