Determination of creatine and phosphocreatine in muscle biopsy samples by capillary electrophoresis with contactless conductivity detection.

A capillary electrophoresis method with contactless conductivity detection was evaluated as a new approach for quantification of creatine and phosphocreatine in human quadriceps femoris biopsy samples. The running buffers employed consisted of 1 M acetic acid at a pH of 2.3 for the determination of creatine and 50 mM 3-(N-morpholino)propanesulfonic acid/30 mM histidine at a pH of 6.

Capillary electrophoresis with contactless conductivity detection for the determination of carnitine and acylcarnitines in clinical samples.

A capillary electrophoresis method with contactless conductivity detection was developed for the quantification of carnitine and six acylcarnitines in plasma and urine samples. The running buffer employed consisted of 500 mmol/L acetic acid, 1.0 mmol/L hydroxypropyl-β-cyclodextrin and 0.

Quantification of plasma lactate concentrations using capillary electrophoresis with contactless conductivity detection.

The quantification of plasma lactate and evaluation of the lactate threshold by CE with capacitively coupled contactless conductivity is demonstrated. The only sample preparation needed was deproteinization with a ACN/methanol mixture. A solution of 10 mmol/L 2-morpholinoethanesulfonic acid monohydrate, 10 mmol/L DL-histidine, 70 μmol/L hexadecyltrimethylammonium bromide, pH 6.

Determination of carnitine in food and food supplements by capillary electrophoresis with contactless conductivity detection.

A CE method with capacitively coupled contactless conductivity detection was developed and tested for the quantification of carnitine in different types of foodstuffs, namely fruit juices, milk, yogurt, cheese, red meat and chicken meat. Sample preparation was minimal as chemical or enzymatic conversion of the analyte is not necessary with the non-UV-absorbing compound when conductivity detection is employed. A 500 mmol/L acetic acid solution at pH 2.

Determination of the enantiomers of alpha-hydroxy- and alpha-amino acids in capillary electrophoresis with contactless conductivity detection.

The enantiomers of the anions of five alpha-hydroxy acids, namely lactic acid, alpha-hydroxybutyric acid, 2-hydroxycaproic acid, 2-hydroxyoctanoic acid and 2-hydroxydecanoic acid, as well as the two alpha-amino acids aspartic acid and glutamic acid, were baseline separated and detected by CE with contactless conductivity detection. Vancomycin was employed as chiral selector and could be used with conductivity detection without having to resort to a partial filling protocol as needed when this reagent is used with UV absorbance measurements. The procedure was successfully applied to the determination of the lactic acid enantiomers in samples of milk and yogurt.

Capillary electrophoresis with contactless conductivity detection for uric acid determination in biological fluids.

The suitability of capillary electrophoresis (CE) with capacitively coupled contactless conductivity detection (C(4)D) for the direct determination of uric acid in human plasma and urine was investigated. It was found that a careful optimization of the buffer composition and pH was necessary to achieve selective determination in the complex sample matrices. An electrolyte solution consisting of 10mM 2-morpholinoethanesulfonic acid (MES), 10mM histidine and 0.