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Updated: Jan 10, 2026

Synthetic Methodology for Asymmetric Ferrocene Derived Bio-conjugate Systems via Solid Phase Resin-based Methodology
Published on: March 12, 2015
Catalytically controlled formation of coumarin-based hydrogelator enables colorimetric ferrous ion detection in sol
Nikita Das1, Samir Mandal2, Sib Sankar Mal3
1(Organic)Materials and Engineering Laboratory, CNBT, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, 632014, India.
Abstract:
In-situ generation of a hydrogelator from non-assembling precursors offers an effective strategy for preparing supramolecular hydrogel materials with precise spatiotemporal control. These hydrogels hold broad potential for applications ranging from theranostics to chemical sensing. Herein, we report a method for the in-situ formation of a coumarin-based supramolecular hydrogelator by simply mixing aqueous solutions of two non-assembling precursors under ambient conditions. The formation of the hydrogelator, its subsequent self-assembly into a hydrogel network, and the resulting material properties can all be modulated via acid catalysis. The hydrogelator exhibits excellent selectivity toward Fe(II) ions, providing a distinct colorimetric response with a linear correlation and a notable detection limit. Additionally, the hydrogel material can be easily applied to disposable paper strips, enabling convenient and portable detection of Fe(II) ions. This system demonstrates strong potential for addressing key challenges in Fe(II) ion sensing in both aqueous environments and self-assembled hydrogel states.
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