Conformational Analysis of Xanthan and Welan Using Electron Microscopy
Electron microscopy of xanthan indicates that this biopolymer can exist as a single- or double-stranded or partly dissociated double-stranded structure depending on the ionic strength prior to preparation for electron microscopy. Welan appears as a uniform thick, convoluted structure with contour length varying from molecule to molecule. The two-dimensional spatial correlation of the tangent direction indicates that the persistence length of double-stranded xanthan in 100mM ammonium acetate is 150 nm; the persistence length of single-stranded xanthan in 2 mM ammonium acetate is observed to be 60 nm and the persistence length of welan in 100 mM ammonium acetate is observed to be 80 nm.
KeywordsAmmonium Acetate Intrinsic Viscosity Tangent Direction Flocon 4800 Persistence Length
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