《A chitosan-based fluorescent hydrogel for selective detection of Fe2+ ions in gel-to-sol mode and turn-off fluorescence mode》 was published in Polymer Chemistry in 2019. These research results belong to Fan, Kaiqi; Wang, Xiaobo; Yu, Shuyan; Han, Guanglu; Xu, Die; Zhou, Liming; Song, Jian. Product Details of 112881-51-3 The article mentions the following:
A novel chitosan-based fluorescent hydrogel has been synthesized by chem. bonding terpyridine-bearing aldehydes onto chitosan via an acid condensation reaction. More interestingly, such a hydrogel works as a dual-mode chemosensor for selective, rapid, gel-to-sol, and turn-off fluorescence sensing of Fe2+ ions. In the gel-to-sol mode, the detection limit for Fe2+ ions is 0.28 ppm, and in the turn-off fluorescence mode, the detection limit is 3.8 ppb. Such hydrogel-based fluorescent chemosensors are potentially suitable for the monitoring of Fe2+ in biol. and environmental applications. In the part of experimental materials, we found many familiar compounds, such as 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3Product Details of 112881-51-3)
4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. Product Details of 112881-51-3 Pyridine has a conjugated system of six π electrons that are delocalized over the ring.