Carmellose (Carboxymethylcellulose) is used as a binder of tablets, disintegrators and stabilizers; it is widely used in cosmetics and foods. Carmellose is an anionic polysaccharide with carboxyl groups. Anionic samples may elute earlier due to ion exclusion interaction between the sample and packing materials hence leading to a larger than expected calculated molecular weight. Addition of salt to the eluent will decrease the ion exclusion interactions. The effect of increased salt concentration in the eluent is shown for the analysis of Carmellose. It was confirmed that peak shape stabilized at a concentration > 50 mM NaCl.


Sample : Carboxymethylcellulose (400-800 cP) 0.1 %, 50 μL

Columns      : Shodex OHpak SB-806M HQ (8.0 mm I.D. x 300 mm) x 2
Eluent       : H2O or NaCl aq.
Flow rate    : 1.0 mL/min
Detector     : RI
Column temp. : 40 °C