Maleimide-Functionalized Thiol Reactive Copolymer Brushes: Fabrication and Post-Polymerization Modification

Abstract

Polymer brushes that present side chain functional reactive groups are attractive platforms for the development of functional surface coatings. From the wide spectrum of possible postpolymerization modification reactions, thiol-based conjugation chemistries are particularly appealing as they can be performed reagent-less under mild conditions and can allow the site-selective conjugation of biomolecules. This manuscript reports a direct approach for the preparation of maleimide-functionalized polymer brushes. These brushes were obtained by surface-initiated atom transfer radical copolymerization of poly(ethylene glycol) methacrylate and a furan-protected, maleimide containing monomer, followed by a thermally induced retro Diels−Alder reaction to unmask the maleimide groups. The feasibility of these brushes to serve as a platform for postpolymerization functionalization was explored in a series of model experiments using a variety of low molecular weight thiols, including a fluorescent dye and a thiol-modified biotin-derivative. The biotinylated brushes were subsequently used for the immobilization of streptavidin-coated quantum-dots. The copolymer brushes presented in this manuscript are attractive since they combine the nonbiofouling properties of the poly(ethylene glycol) methacrylate monomer with the chemoselective reactivity of the maleimide containing monomer, which makes them an attractive platform, e.g., for the immobilization of biomolecules.

Fabrication of Thiol–Ene “Clickable” Copolymer-Brush Nanostructures on Polymeric Substrates via Extreme Ultraviolet Interference Lithography

“…This reaction step is expected to be nearly quantitative. 55 It could be detected as a minor shift in the ATR-IR spectra of the imide CO vibration of the conjugated amide rDA product (Supporting Information Figure S4) and the appearance of strong bands at 830 and 696 cm −1 for cisconjugated sp 2 CH vibrations, respectively (Supporting Information Figure S5). …”

“…54 Maleimide-containing polymer brushes were fabricated on silicon oxide surfaces using copper-mediated atom transfer radical polymerization (ATRP). 55 This approach entails immobilization of specific radical initiators on the siliconbased substrate, followed by metal-mediated polymerization. Needless to say, development of a universal method for fabrication of thiol-reactive brushes on polymeric substrates will expand their versatility.…”

Maleimide-Functionalized PEI600 Grafted Polyurethane: Synthesis, Nano-Complex Formation with DNA and Thiol-Conjugation of the Complexes for Dual DNA Transfection

“…To obtain conjugates of PU-PEI 600 -maleimide/DNA complexes, these two different PU-PEI 600 -maleimide/DNA complexes were reacted with 1.6-hexanedithiol dissolved in HEPES buffer via a reaction between maleimide and SH [11,12]. The thiol-conjugated reaction was conducted for 30 min at room temperature and the condition (as an optimal molar ratio of PU-PEI 600 -maleimide/dithiol) for preparation of the conjugates was studied.…”

Maleimidophenyl isocyanates as postpolymerization modification agents and their applications in the synthesis of block copolymers

“…Functional polymers with reactive sites are widely used as components for smart materials. Maleimides are highly reactive, exemplified by their thiol–ene click reactions with thiol reagents, reversible Diels–Alder reactions with furans, alternating copolymerization reactions with vinyl monomers such as styrene, and photoactivated reactions . Due to their high and selective reactivity, maleimides have been extensively studied, whereby growing interest has been focused on the application of maleimides in polymer chemistry for the development of well‐designed functional materials.…”