Rapid determinations of saccharides in high-energy drinks by short-capillary electrophoresis with contactless conductivity detection.
The methodology for separations of saccharides in standard electrophoretic systems has been transferred to the short-capillary electrophoresis format. The laboratory-designed apparatus used employs a quartz capillary with an internal diameter of 10 μm, a total length of 10 cm, and an effective length of 4 cm, in combination with contactless conductivity detection. It has been applied to separations of neutral mono- and disaccharides. The saccharides are separated in the anionic form, in solutions of alkali hydroxides, namely, KOH, NaOH, and LiOH. The separation of a model mixture of five saccharides (sucrose, lactose, glucose, fructose, and ribose) takes less than 1 min, the LOD equaling 15, 35, 19, 17, and 24 mg L(-1) and the LOQ equaling 52, 117, 63, 53, and 79 mg L(-1) for sucrose, lactose, glucose, fructose, and ribose, respectively. The technique developed has been used to determine sucrose, glucose and fructose in high-energy drinks. The separation is finished within less than 50 s; the saccharide contents determined are identical with the declared values within the reliability interval in most cases, the RSD value being mostly less than 2%. In general, the separation system developed is very convenient for rapid analyses of large sets of similar samples, e.g., in product quality control or environmental monitoring.
Faculty of Science, Department of Analytical Chemistry, Charles University in Prague, Prague, Czech Republic.
Blanka
B
Vochyánová
František
F
Opekar
Petr
P
Tůma
Karel
K
Štulík
D004553:Electric Conductivity; D019075:Electrophoresis, Capillary / Q000191:economics / Q000295:instrumentation*; D061215:Energy Drinks / Q000032:analysis*; D004867:Equipment Design; D057230:Limit of Detection; D009005:Monosaccharides / Q000032:analysis* / Q000302:isolation & purification; D013395:Sucrose / Q000032:analysis* / Q000302:isolation & purification; D013997:Time Factors
D009005:Monosaccharides; D013395:Sucrose