Assembly of debranched xylan from solution and on nanocellulosic surfaces.
This study focused on the assembly characteristics of debranched xylan onto cellulose surfaces. A rye arabinoxylan polymer with an initial arabinose/xylose ratio of 0.53 was debranched with an oxalic acid treatment as a function of time. The resulting samples contained reduced arabinose/xylose ratios significantly affecting the molecular architecture and solution behavior of the biopolymer. With this treatment, an almost linear xylan with arabinose DS of only 0.04 was obtained. The removal of arabinose units resulted in the self-assembly of the debranched polymer in water into stable nanoparticle aggregates with a size around 300 nm with a gradual increase in crystallinity of the isolated xylan. Using quartz crystal microbalance with dissipation monitoring, the adsorption of xylan onto model cellulose surfaces was quantified. Compared to the nonmodified xylan, the adsorption of debranched xylan increased from 0.6 to 5.5 mg m(-2). Additionally, adsorption kinetics suggest that the nanoparticles rapidly adsorbed to the cellulose surfaces compared to the arabinoxylan. In summary, a control of the molecular structure of xylan influences its ability to form a new class of polysaccharide nanoparticles in aqueous suspensions and its interaction with nanocellulose surfaces.
Wallenberg Wood Science Center and ‡Biopolymer Technology, Department of Chemical and Biological Engineering, Chalmers University of Technology , Gothenburg 412 96, Sweden.
Toon J
TJ
Bosmans
Agnes M
AM
Stépán
Guillermo
G
Toriz
Scott
S
Renneckar
Erdem
E
Karabulut
Lars
L
Wågberg
Paul
P
Gatenholm
D000327:Adsorption; D001704:Biopolymers / Q000737:chemistry; D002482:Cellulose / Q000737:chemistry; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*; D058525:Quartz Crystal Microbalance Techniques; D012996:Solutions; D013499:Surface Properties; D014867:Water / Q000737:chemistry; D014990:Xylans / Q000737:chemistry*
D001704:Biopolymers; D011134:Polysaccharides; D012996:Solutions; D014990:Xylans; D014867:Water; D002482:Cellulose; C085118:arabinoxylan