Asymmetric cellulose nanocrystals: thiolation of reducing end groups via NHS-EDC coupling

作者：Arcot Lokanathan R^*; Lundahl Meri; Rojas Orlando J; Laine Janne

来源：Cellulose, 2014, 21(6): 4209-4218.

DOI：10.1007/s10570-014-0426-9

• Cellulose nanocrystals
• Reducing end
• Thiolation
• Chemisorption

Cellulose nanocrystals (CNC) were functionalized in aqueous media at the reducing, aldehyde ends of cellulose. CNC oxidation to produce carboxyl groups was followed by carbodiimide-mediated reaction to install thiol groups. The selectivity and extent of thiolation at the reducing ends was qualitatively confirmed by imaging (transmission electron microscopy) silver nanoparticles that tagged the CNC termini and by X-ray photoelectron spectroscopy, respectively. The adsorption of thiolated CNC onto gold surfaces as well as the viscoelastic property of the formed adlayer was investigated by using quartz crystal microgravimetry. The thiolated CNC chemisorbed on the surfaces were further analyzed for surface density and distribution by using atomic force microscopy. Overall we introduce a facile, mild asymmetric thiolation procedure as an efficient alternative to conventional reductive amination.

• 出版日期2014-12