Fingerprinting polysaccharides with single-molecule atomic force microscopy.

Journal Article (Journal Article)

We report the use of an atomic force microscopy (AFM)-based force spectroscopy technique to identify, at the single-molecule level, the components of mixtures of polysaccharides. Previously, we showed that the elasticity of certain types of polysaccharides is governed by force-induced conformational transitions of the pyranose ring. These transitions produce atomic fingerprints in the force-extension spectrum that are characteristic of the ground-energy conformation of the pyranose ring and the type of glycosidic linkages. Using this approach we find that commercially available agarose and lambda-carrageenan contain molecules that, when stretched in an atomic force microscope, produce a force spectrum characteristic of alpha-(1-->4) d-glucans. We have identified these molecules as amylopectin or floridean starch, a storage polysaccharide in algae. Our methodology can identify individual polysaccharide molecules in solution, which is not possible by any other spectroscopic technique, and therefore is an important addition to the arsenal of analytical techniques used in carbohydrate research.

Full Text

Duke Authors

Cited Authors

  • Marszalek, PE; Li, H; Fernandez, JM

Published Date

  • March 2001

Published In

Volume / Issue

  • 19 / 3

Start / End Page

  • 258 - 262

PubMed ID

  • 11231560

Electronic International Standard Serial Number (EISSN)

  • 1546-1696

International Standard Serial Number (ISSN)

  • 1087-0156

Digital Object Identifier (DOI)

  • 10.1038/85712


  • eng