Fast determination of sugars in Coke and Diet Coke by miniaturized capillary electrophoresis with amperometric detection.
The fast separation capability of a novel miniaturized capillary electrophoresis with amperometric detection (CE-AD) system was demonstrated by determining sugar contents in Coke and diet Coke with an estimated separation efficiency of 60,000 TP/m. Factors influencing the separation and detection processes were examined and optimized. The end-capillary 300 microm Cu wire amperometric detector offers favorable signal-to-noise characteristics at a relatively low potential (+0.50 V vs. Ag/AgCl) for detecting sugars. Three sugars (sucrose, glucose, and fructose) have been separated within 330 s in a 8.5 cm length capillary at a separation voltage of 1000 V using a 50 mM NaOH running buffer (pH 12.7). Highly linear response is obtained for the above compounds over the range of 5.0 to 2.0 x 10(2) microg/mL with low detection limit, down to 0.8 microg/mL for glucose (S/N = 3). The injection-to-injection repeatability for analytes in peak current (RSD < 3.6%) and for migration times (RSD < 1.4%) was excellent. The new miniaturized CE-AD system should find a wide range of analytical applications involving assays of carbohydrates as an alternative to conventional CE and micro-CE.
Chu
Qingcui
Q
Department of Chemistry, East China Normal University, Shanghai 200062, PR China.
Fu
Liang
L
Guan
Yueqing
Y
Ye
Jiannong
J
D002241:Carbohydrates / Q000032:analysis* / Q000737:chemistry; D002253:Carbonated Beverages / Q000032:analysis*; D019075:Electrophoresis, Capillary / Q000379:methods*; D008832:Microchemistry / Q000379:methods*; D008904:Miniaturization; D013997:Time Factors
D002241:Carbohydrates