Selective ligand-doped liquid crystal-based sensor for detection of ferric cation

A liquid crystal (LC) sensing platform was developed for detection of ferric ion (Fe3+) in aqueous solutions. In this platform, a N and S comprising ligand (2E)-2-(naphthylmethylene)hydrazinecarbothioamide (CTA) was doped in 4-cyano-4’-pentyl biphenyl (5CB) as the Fe3+ selective LCs. When the platform was submerged in the solution comprising Fe3+, the complex between Fe3+ and CTA formed, which disturbed the orientation of LC and cause a dim-to-light conversion of the picture of LCs. Based on previous studies, it has been suggested that 2:1 Fe3+: CTA complex were formed. The limit of detection of the platform for Fe3+ is 0.03 µM. This sensing platform did not respond to Ca2+, Cd2+, Mg2+, Cu2+, Na+, Zn2+, Pb2+ and Hg2+ metal ions. Furthermore, we also represented that this sensing platform is able to detecting Fe3+ in piped water. Due to the fact, the sign of this sensing platform is coloured under environmental light, which is easily comprehended by ordinary operators, it could be utilised as a mobile device to check the quality of water in any one place.