Grafted poly(1→4-β-glucan) strands on silica: A comparative study of surface reactivity as a function of grafting density

Oz M. Gazit, Alexander Katz

Research output: Contribution to journalArticlepeer-review

Abstract

Grafted poly(β-glucan) (β-glu) strands on the surface of silica are synthesized with varying degrees of grafting density, and display an amorphous-like environment via 13C CP/MAS NMR spectroscopy. Thermal gravimetric analysis of these materials under oxidative conditions shows increased β-glu thermal stability with higher degrees of grafting density. The range of temperature stability between the most and least hydrogen-bound grafted β-glu strands spans 321 to 260 °C. This range is bound by the combustion temperature previously measured for crystalline and amorphous cellulose, with the former having greater oxidative stability, and is likely controlled by the extent of hydrogen bonding of a grafted β-glu strand with the underlying silica surface. When using these materials as reactants for glycosidic bond hydrolysis, the total number of reducing ends formed during reaction is quantified using a BCA colorimetric assay. Results demonstrate that the material with greatest interaction with silica surface silanols undergoes hydrolysis at an initial rate that is 6-fold higher than the material with the lowest degree of such interaction. The role of the surface as a reactive interface that can endow oxidative stability and promote hydrolysis activity has broad implications for surface-catalyzed processes dealing with biomass-derived polymers.

Original languageEnglish
Pages (from-to)431-437
Number of pages7
JournalLangmuir
Volume28
Issue number1
DOIs
StatePublished - 10 Jan 2012
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Spectroscopy
  • General Materials Science
  • Surfaces and Interfaces
  • Electrochemistry

Fingerprint

Dive into the research topics of 'Grafted poly(1→4-β-glucan) strands on silica: A comparative study of surface reactivity as a function of grafting density'. Together they form a unique fingerprint.

Cite this