Analysis of monosaccharides in the saffron corm glycoconjugate by capillary electrophoresis

The monosaccharides in the saffron corm glycoconjugate were separated by capillary electrophoresis (CE) coupled with pre-column derivatization. 4-Methoxyaniline was used as derivatization reagent. The derivatization and CE separation conditions were investigated. The ultraviolet detection wavelength was 234 nm. The maximum yield of this derivatization reaction was obtained under the presence of 9.5% (v/v) acetic acid at 80 °C for 2 h. An uncoated fused-silica capillary of 50 μm i.d. and 50/60 cm length (effective length/total length) was employed, and a pressure injection(3.4475 kPa, 5 s) was applied. The baseline separation of 11 monosaccharides and disaccharides (lyxose, xylose, ribose, glucose, mannose, galactose, rhamnose, cellobiose, maltose, lactose, fructose) was reached at 25 °C, 20 kV of separation voltage and with 350 mmol/L boric acid (pH 10.21) as running buffer. The developed method has been successfully applied to quantitatively determine the components of saffron corm glycoconjugate, and the results showed that the recovery of each monosaccharide was in the range of 94.3%-105.4%, the relative standard deviation was 3.3%-4.6%.