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Tuberculosis is a devastating contagious disease caused by Mycobacterium tuberculosis. This is the first report describing the development of novel capillary electrophoresis methods to detect lipoarabinomannans shed into the blood circulation by replicating bacteria. The novelty of the methods is the detection without derivatization. The lipoarabinomannan is detected owing to the ionization of the diverse functional groups of the structure, such as the multibranched mannan domain or the phosphatidyl group. Four alkaline solutions were used; normal polarity in three of them and reversed polarity in one. Urinary lipoarabinomannans by saccharide domains were identified with direct absorbance detection. The accuracy and the analytical sensitivity were then validated with cello-, manno- and xylooligosaccharides. Lipoarabinomannan detection was feasible within 20 min (RSD 2.1%). This method worked at the dynamic range of 0.1-10 μg/mL. With reversed polarity, indirect absorbance detection, and pH 9.0 electrolyte were used, the analytes migrated already within 5 min (RSD 0.01%). Inorganic nonabsorbing ions were used for this method optimization. This improvement resulted in the detection limit of 1 pg/mL in water and in the linear dynamic range of 1 pg/mL to 10 ng/mL. In conclusion, the described method has great potential as a point-of-care assay for clinical use.

Tuberculosis is a devastating contagious disease caused by Mycobacterium tuberculosis. This is the first report describing the development of novel capillary electrophoresis methods to detect lipoarabinomannans shed into the blood circulation by replicating bacteria. The novelty of the methods is the detection without derivatization. The lipoarabinomannan is detected owing to the ionization of the diverse functional groups of the structure, such as the multibranched mannan domain or the phosphatidyl group. Four alkaline solutions were used; normal polarity in three of them and reversed polarity in one. Urinary lipoarabinomannans by saccharide domains were identified with direct absorbance detection. The accuracy and the analytical sensitivity were then validated with cello-, manno- and xylooligosaccharides. Lipoarabinomannan detection was feasible within 20 min (RSD 2.1%). This method worked at the dynamic range of 0.1-10 μg/mL. With reversed polarity, indirect absorbance detection, and pH 9.0 electrolyte were used, the analytes migrated already within 5 min (RSD 0.01%). Inorganic nonabsorbing ions were used for this method optimization. This improvement resulted in the detection limit of 1 pg/mL in water and in the linear dynamic range of 1 pg/mL to 10 ng/mL. In conclusion, the described method has great potential as a point-of-care assay for clinical use.

This paper demonstrates the use of the first on-line capillary electrophoresis instrument with continuously flowing electrolyte solutions and sequentially applied sample introduction. The system was used in on-line determination of chloride, sulphate and carbonate concentrations of process waters at a pulp mill. The module constructed for on-line feedings of the solvents is described. Separations were performed in a pyromellitic acid-hexamethonium hydroxide-triethanol amine mixture at pH 7.7 with indirect-UV detection at 254 nm. Two standard mixtures were used to show the repeatability of the analysis and to estimate the accuracy of the on-line system. The analytes could be separated within 240 s. Sampling from a pulp machine could be accomplished on-line at 6 minute intervals. On-line tests gave a limit of detection and a limit of determination in the low mg/L range.

Until now, partial filling micellar EKC-ESI-MS (PF-MEKC-ESI-MS) has seldom been applied for human biomolecules. In this study, determination of three electrically neutral endogenous steroid hormones, namely androstenedione, testosterone, and epitestosterone, by PF-MEKC-ESI-MS was investigated. Since ESI-MS and ESI-MS/MS behaviors of testosterone and epitestosterone proved to be nearly identical, efficient separation of the two compounds was required to obtain reliable identification. The chemical conditions as well as the instrumental parameters affecting the PF-MEKC-ESI-MS analysis were researched. In optimal conditions, ESI-MS showed excellent selectivity, and all the steroids could be identified using SIM. LODs were 0.75-5 microg/mL. The results obtained by PF-MEKC-ESI-MS were compared with those obtained by corresponding PF-MEKC-UV. PF-MEKC-UV provided better resolution, repeatability, and more than ten-fold higher sensitivity, in terms of LODs, than PF-MEKC-ESI-MS. The reasons for this were carefully examined. In comparison with PF-MEKC-UV, PF-MEKC-ESI-MS suffered from greater band broadening owing to the sheath-liquid interface. Resolution was also decreased owing to the elevated capillary temperature. Finally, we discovered that in the analysis of electrically neutral compounds, in-capillary sample concentration by micellar sweeping could be more efficiently utilized in PF-MEKC-UV than in PF-MEKC-ESI-MS.