Fast and sensitive visual detection of Fe2+ using silver nanoparticles modified with 3,3',5,5'-tetramethylbenzidine
Qian Wang1, Xiaoyun Li1, Haiyan Zhang1
1Department of Physical and Chemical Inspection, Center for Disease Control and Prevention of Yancheng, Yancheng, 224000, Jiangsu, China. 1059452181@qq.com.
None:
In this work, a novel sensitive colorimetric sensor was constructed for the determination of iron(II) (Fe2+) via modifying 3,3',5,5'-tetramethylbenzidine and 3-mercaptopropionic acid on the surface of silver nanoparticles. In the presence of Fe2+, the modifying groups interacted with Fe2+, which caused the color of the solution to change, and the absorption peak at 395 nm decreased, while a new absorption peak appeared at 525 nm. This method exhibited good selectivity and sensitivity for the determination of Fe2+ which was found by observing the color of the system with the naked eye and calculating the ratio of A525 and A404, and the linear range was from 0.5 × 10-6 M to 1.00 × 10-5 M and the limit of visual colorimetric detection was 500 nM. This method has great potential for the rapid detection of iron(II) in environmental samples, including successful applications in tap water and lake water analysis.
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