Sensing of polymeric sensor-based rhodamine B derivative for metal cations in complete aqueous solution

The water-soluble polymeric chemosensor poly(AM-GRBD) has been synthesized by precipitation copolymerization with the functional monomer, GRBD, which was made of N \(^{\boldsymbol {\prime \prime }}\) -(rhodamine B-yl) diethylenetriamine and glycidyl methacrylate (GMA) and a hydrophilic co-monomer acrylamide (AM). The chemical sensor behaved as a fluorescent and chromogenic sensor towards various heavy metal cations and transition metal cations; particularly, Cr 3+ , Fe 3+ and Hg 2+ ions in completely aqueous media. The fluorescence of poly(AM-GRBD) was enhanced by Cr 3+ , Fe 3+ and Hg 2+ metal ions. Moreover, during titration of Cr 3+ , Hg 2+ or Fe 3+ to the aqueous solution of poly(AM-GRBD), the visual colour changed from colourless to pink or brown yellow under visible light.