Ding Chenxu

Separation of Derivatized Carbohydrates by Capillary Zone Electrophoresis

Abstract A simple and rapid method was developed for the separation of the labeled carbohydrates using 1-naphthyl-3-methyl-5- pyrazolone (NMP) as the derivatization reagent by capillary zone electrophoresis. A 58.5 cm × 50 μm i.d. (50 cm effective length) untreated fused-silica capillary is used. To optimize the conditions, the buffer solution concentration, pH, column temperature, voltage and other factors are evaluated. The results indicate that the buffer concentration and pH value exhibit a significant impact on the separation, but no obvious influences of the temperature, voltage and additives on resolution are observed. On the basis of the optimization, the optimal separation conditions are as follows: 55 mM borate buffer (pH 9.46), voltage of 22 kV, column temperature of 20 °C and DAD detection of 254 nm. The samples are introduced atmospherically with an injection time of 10 s. The results indicate that nine NMP-labeled carbohydrates can be separated with a good baseline resolution within 18 min under the conditions proposed. The Tangutoium Nitratia sample is also analyzed under the optimum conditions. The separation is efficient and rapid with satisfactory results.