Synthesis Of Fluorescent Polyacrylamide Based On DansylChloride [5-Dimethylaminonaphthalene-1-SulfonylChloride]Author(s): Enayatollah Mottaghinejad, Seyed Hossein Hosseini, Maryam Pakzad Masoleh
During the past decades, research on fluorescent polymers has become an interesting area due to their versatile applications as luminescent probes in various fields. The assembling of many fluorophores onto a polymer chain affords the polymer high brightness under conventional microscope. In general, there are two ways to synthesize such fluorophore-enriched polymers. One of them is the polymerization of a polymerizable fluorescent monomer with some common monomers; the other is the chemical modification of polymers by fluorescent molecules or fluorescent oligomers. Fluorescent polymers with different polarity and functionalization are synthesized for various applications. We found that polyacrylamide can react by a nucleophilic substitution mechanism with dansyl chloride [5-Dimethylaminonaphthalene-1-sulfonyl chloride]. This reaction takes places under dilute sodium hydroxide in water/methanol or dimethylsulfoxide solvent system to afford fluorescent dansylated polyacrylamide in good yield. The fluorescent property of the polymer is well established by different methods such as spectrofolurimetry, visualization under uv-lamp, preparation of fluorescent strips of filter paper by dipping into the polymer solution and other methods. Spectroscopic data such as H-NMR, FT-IR and UV-Visible are well correspond with the bond formation of the polymer amide nitrogen to the dansyl moiety.