A selective colorimetric chemosensor for Fe3
Min-Hsiu Kao1, Chin-Feng Wan2, An-Tai Wu1
1Department of Chemistry, National Changhua University of Education, Changhua, Taiwan.
Abstract:
Two simple colorimetric receptors PS and PP (thiophene and pyridine appended derivative) were prepared and their cation sensing properties were investigated. Receptors PS and PP displayed a selective colorimetric change (from colorless to orange) upon binding to Fe3+ in MeOH solution. The association constants for receptors PS-Fe3+ and PP-Fe3+ in MeOH were determined to be 1.15 × 106 and 4.31 × 106 M-1 , respectively, using Hill plots. The detection limits of PS and PP were 490.7 ppm and 393.7 ppm, respectively.
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