Abstract
A bacterial polysaccharide, gellan gum, was deposited on highly oriented pyrolytic graphite and was studied by means of scanning tunneling microscopy. The sample was prepared in the presence of cations to make double helices of gellan associate into cation-mediated aggregates. This study is the first direct confirmation of the helix structure of gellan in the real space. An image of a cross-linking domain, observed in the ambient condition, showed that half a pitch of the double helix was ca 2.6nm and that the separation of strands was ca 2.3nm. The effect of co-existing cations on the strength of macroscopic gels was discussed in relation to the microscopic structures observed by STM. The difference of cations mainly influenced the length of strands of gellan.
| Original language | English |
|---|---|
| Pages (from-to) | 77-81 |
| Number of pages | 5 |
| Journal | Carbohydrate Polymers |
| Volume | 30 |
| Issue number | 2-3 |
| DOIs | |
| Publication status | Published - 1996 Jan 1 |
ASJC Scopus subject areas
- Organic Chemistry
- Polymers and Plastics
- Materials Chemistry