Light-Emitting Multifunctional Maleic Acid-<i>co</i>-2-(<i>N</i>-(hydroxymethyl)acrylamido)succinic Acid-<i>co</i>-<i>N</i>-(hydroxymethyl)acrylamide for Fe(III) Sensing, Removal, and Cell Imaging

Abstract

The intrinsically fluorescent highly hydrophilic multifunctional aliphatic terpolymer, maleic acid (MA)-<i>co</i>-2-(<i>N</i>-(hydroxymethyl)acrylamido)succinic acid (NHASA)-<i>co</i>-<i>N</i>-(hydroxymethyl)acrylamide (NHMA), that is, <b>1</b>, was designed and synthesized via C-C/N-C-coupled in situ allocation of a fluorophore monomer, that is, NHASA, composed of amido and carboxylic acid functionalities in the polymerization of two nonemissive MA and NHMA. The scalable and reusable intrinsically fluorescent biocompatible <b>1</b> was suitable for sensing and high-performance adsorptive exclusion of Fe(III), along with the imaging of Madin-Darby canine kidney cells. The structure of <b>1</b>, in situ fluorophore monomer, aggregation-induced enhanced emission, cell-imaging ability, and superadsorption mechanism were studied via microstructural analyses using ¹H/¹³C NMR, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, atomic absorption spectroscopy, ultraviolet-visible spectroscopy, thermogravimetric analysis, dynamic light scattering, high-resolution transmission electron microscopy, solid-state fluorescence, fluorescence lifetime, and fluorescence imaging, along with measuring kinetics, isotherms, and thermodynamic parameters. The location, electronic structures, and geometries of the fluorophore and absorption and emission properties of <b>1</b> were investigated using density functional theory and natural transition orbital analyses. The limit of detection and the maximum adsorption capacity were 2.45 × 10^-7 M and 542.81 mg g^-1, respectively.