Hydrazides dextran modified

The ethylene diamine-dextran derivative may be used for the coupling of carboxylate-contain-ing molecules by the carbodiimide reaction, for the coupling of amine-reactive probes, or to modify further using heterobifunctional crosslinkers. The hydrazide-dextran derivative may be used to crosslink aldehyde-containing molecules, such as oxidized carbohydrates or glycoproteins. 

Figure 25.19 Polyaldehyde dextran may be modified with the hydrazide end of M2C2H to create a thiol-reactive polymer.

The technique is also used to introduce diene moieties, which enable the polymer for a highly efficient modification with dienophile components via Diels-Alder reaction [354], Therefore, methyl octa-4,6-dienoate is converted to octa-4,6-dienoic acid hydrazide, which is bound to dextran via reaction with BrCN. The maleimide-modified protein (albumin) is easily attached to the polymer backbone by Diels-Alder reaction (Fig. 50). 

Figure 8.7 Schematic representation of injectable hydrogels reinforced with cellulose nanocrystals (CNCs), prepared using a double-barrel inge. The crosslinking hydrogel components include hydrazide-fiinctionalized car-boxymethyl cellulose (CMC-NHNH2), aldehyde-functionalized dextran (dextran-CHO), and either unmodified CNCs or aldehyde-modified CNCs (CHO-CNCs).

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