Well‐Defined Glycopolymers via RAFT Polymerization: Stabilization of Gold Nanoparticles

Abstract

Well‐defined glycopolymers of poly(2‐{[(d‐glucosamin‐2‐N‐yl)carbonyl]oxy}ethyl meth(acry­late)) (PHEMAGl and PHEAGl, respectively) are first synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization in green solvents such as water and dimethyl sulfoxide (DMSO). The biomolecular recognition of the synthesized glycopolymers bearing glucose residues toward Concanavalin A lectin is confirmed by turbidimetric assays. Subsequently, HEMAGl glycopolymer is mixed with gold nanoparticles in the presence of sodium borohydride, which reduces the terminal groups to thiol and yields the preparation of synthetic carbohydrate polymer‐stabilized gold nanoparticles showing enhanced colloidal stability. The resulting glyco‐nanoparticles are characterized by dynamic light scattering (DLS) and field‐emission electron microscopy (FE‐SEM), whereas the molecular recognition abilities are investigated using UV–vis spectroscopy by analyzing the shift in the plasmon band as a consequence of the aggregation variation with the addition of Concanavalin A.

Plasmonic Properties of Colloidal Assemblies

“…In many cases such design benefits from multivalency effects, [ 90 ] since multiple recognition elements are expressed on the exterior of the consequently‐produced NP coating layer. [ 91,92 ] Recently, Gibson and co‐workers implemented dynamic features to this kind of colorimetric assay, by developing systems with externally triggerable recognition element representation. [ 93,94 ] Their concept builds on earlier work by Mirkin and co‐workers [ 95 ] and rests on thermoresponsive PN i PAAM, which was used to shield the recognition elements below its lower critical solution temperature (LCST) and expose them above its LCST, thereby “gating” the sensor capabilities.…”

Glycodendrimers and Modified ELISAs: Tools to Elucidate Multivalent Interactions of Galectins 1 and 3

“…Fluorescent binding assays can be expanded to a microarray format to analyze the influence of glycan valency, structure, and presentation on lectin binding [ 30 , 34 ]. Dynamic light scattering (DLS) is useful for studying the size of glycan/protein nanoparticles formed in solution [ 35 , 36 , 37 , 38 ]. This technique requires large amounts of sample and works best for relatively monodisperse nanoparticles.…”

Glycopolymer Brushes by Reversible Deactivation Radical Polymerization: Preparation, Applications, and Future Challenges

“…N-methyl-d-glucamine and different glucose-and glucosamine-based acrylamide or (meth)acrylate monomers [30,33,43,[45][46][47][48][49][50][51], (Figure 4), either in their linear or ring form, have been synthesized and used for the preparation of well-defined polymer brushes by RDRP methods. The resultant materials have been extensively studied mainly for the specific binding and recognition by lectins [22,24,25,38,39,41,48,49,[51][52][53][54][55][56][57][58]. Very hydrophilic poly(2′-acrylamidoethyl-α-ᴅ-mannopyranoside) (PAAEM), poly(2′acrylamidoethyl-β-ᴅ-galactopyranoside) (PAAEGal) and poly(2′-acrylamidoethyl-β-ᴅglucopyranoside) (PAAEGlc) brushes, prepared by SI-ATRP from silicon substrates in water, exhibited a 149-, 172-, and 500-fold reduction of the non-specific adsorption of bovine serum albumin (BSA), respectively, as well as a 52-, 115-, and 135-fold fibrinogen (Fb) adsorption, respectively, in comparison to uncoated silicone surface [38].…”