| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1200268 | Journal of Chromatography A | 2016 | 7 Pages |
•Simultaneous separation of carbohydrates in ionic liquid solutions was performed.•Statistical design of experiments was applied for the method optimization.•Experimentally formed cellooligomers were separated in ionic liquid samples.
An indirect capillary electrophoresis method for a quantitative determination of mono-, di- and oligosaccharides was developed to investigate biomass degradation, the isomerization of glucose into fructose and conversion of fructose to 5-hydroxymethylfurfural (5-HMF) in ionic liquids (ILs). Three chromophores, namely 2,6-pyridinedicarboxylic acid (PDC), maleic acid and phthalic acid, were used to perform indirect detection. The electroosmotic flow (EOF) was reversed to reduce analysis time, using 1-tetradecyl-3-methylimidazolium chloride (C14MImCl). The simultaneous separation of the underivatized mono-, di- and oligosaccharides was performed using four cellodextrin oligomers (cellotriose, cellotetraose, cellopentaose, cellohexaose), eight carbohydrates (xylose, fructose, glucose, galactose, lactose, cellobiose, raffinose, sucrose), two organic acids (acetic acid, levulinic acid) and 5-HMF. The best performance was obtained using background electrolyte (BGE) composed of 138.2 mM NaOH, 40 mM maleic acid and 5 mM C14MImCl, the applied voltage was −21.7 kV. The linear ranges for analyzed compounds were following: organic acids, raffinose and sucrose from 0.20 to 7 mM, cellodextrin oligomers from 0.25 to 5 mM, other analyzed carbohydrates from 0.25 to 7 mM and 5-HMF from 0.05 to 7 mM. The relative standard deviations (RSD) of peak areas varied from 3.47 to 9.62% during a 5-day analysis period and 0.58–5.29% during one day.
