Access to cross-linked chitosans by exploiting CO₂ and the double solvent-catalytic effect of ionic liquids

Abstract

Fist synthesis of ureido cross-linked chitosans employing the CO2–chitosan–ionic liquid three component system as a way to prepare new biomaterials.

Chiral ionic liquids supported on natural sporopollenin microcapsules

“…Then, an equimolar amount of concentrated H 2 SO 4 was carefully added dropwise at 0 C, and the mixture was stirred at room temperature for 1 hour. 4 ] ionic liquid and the mixture was heated to 160 C for 80 minutes under continuous stirring. The reaction was quenched by adding 100 mL of milliQ water.…”

“…In the last two decades, ionic liquids (ILs) have received increasing interest in the area of green chemistry, 1,2 where they can play an important role as alternative environmentally friendlier media with unique solvent properties, including the peculiar ability to dissolve biopolymers, 3,4 and/or as catalysts for several important reactions. 5,6 However, in contrast to what was generally thought only 10 years ago, it is well-known that ILs also present some drawbacks that need to be addressed: ILs can be more toxic that molecular solvents, their cost is oen higher than that of molecular solvents and they are generally based on petrol derived raw materials.…”

Gradient Chitosan Hydrogels Modified with Graphene Derivatives and Hydroxyapatite: Physiochemical Properties and Initial Cytocompatibility Evaluation

“…The degree of CS-based hydrogel cross-linking was estimated by ninhydrin assay [ 38 ]. 1.5 mg of freeze-dried sample was added to 1 mL of ninhydrin solution and heated in water bath (80 °C) for 20 min.…”

Ionic Liquids Catalysis for Carbon Dioxide Conversion With Nucleophiles

“…[BMIm][OAc] is found to promote the cross-link of chitosan by Guazzelli's group [Figure S13 ; (Mezzetta et al, 2017 )]. Two amino groups in different chitosan chains can react with CO 2 to form urea in [BMIm][OAc].…”