Preparation of efficient magnetic biosorbents by clicking carbohydrates onto graphene oxide

Abstract

In this work, hydrophilic graphene nanosheets (GNS) and the related magnetic nanocomposites were prepared by first tethering alkyne-functionalized graphene oxide (GO) with azide-modified glucose followed by deposition of Fe 3 O 4 nanoparticles on the functionalized GNS. For the preparation of nanohybrids, two approaches were designed: in the first one, after chlorination of GO with thionyl chloride, GO was reacted with propargyl alcohol and subsequently clicked with azideglucoside. The resulted sweet GNS were easily dispersed in water and stable for 2 weeks. In the second approach, GO was functionalized with 3,4,5-tris(prop-2-yn-1-yloxy)benzoic acid via hydroxyl groups on its basal plane and finally treated with azide-glucoside. The obtained hydrophilic GNS were stable in water for 3 weeks. The results showed that both glucose-grafted GO sheets were reduced by sodium ascorbate during click-coupling reaction; this is one of the many advantages of click reaction. Finally, Fe 3 O 4 nanoparticles were deposited on the sweet GNS and were superparamagnetic, responded quickly to an external magnetic field and exhibited efficient adsorption towards methylene blue, as a cationic dye. No leaching was observed even after a week of placing a magnet close to the vial containing the dispersion of magnetic sweet GNS.

Reduced graphene oxide composites with water soluble copolymers having tailored lower critical solution temperatures and unique tube-like structure

“…We have reported carbohydrate and magnetic nanoparticles attachment onto GO via click-reaction3335. To our knowledge, there are not many reports on using ‘grafting from’ method, RAFT-polymerization and click reaction together to prepare graphene nanocomposites.…”

Monochlorotriazinyl‐β‐cyclodextrin Grafted on Graphene Oxide as an Attractive Green Heterogeneous Nanoreactor for Selective Oxidation Reaction with NBS in Water

“…It is possible that functionalization of GO with MCT‐β‐CD could have led to the formation of graphite‐like platelets. Compared with GO, the XRD pattern of the GO‐MCT‐β‐CD showed some new peaks at 2θ=32° and 45.5°, corresponding to MCT‐β‐CD pattern and indicating that the attachment of MCT‐β‐CD occurred to the GO support …”

Click Chemistry Enabling Covalent and Non-Covalent Modifications of Graphene with (Poly)saccharides

“…The same research group later on reported on an extension of their first work on “sweet-graphene” in which they employed two different CuAAC click-reactions in order to achieve basal plane and edges functionalization of GO with glucose. (see Figure 8 ) [ 56 ]. In a similar fashion as before, this required the pre-alkyne modification of GO at the edge -COOH entities or at the -OH basal plane entities ( Figure 8 ).…”