Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1242532 | Talanta | 2011 | 5 Pages |
Abstract
A novel long drop time mercury electrode has been constructed from common fused-silica capillary (50 μm I.D., 360 μm E.D.). Proposed device provides reproducible mercury drops with typical lifetime 40-120 s. The electrode was used for a set of electrocapillary measurements aimed at determination of critical micelle concentration of anionic surfactants by a convection controlled drop-time technique. A critical micelle concentration of sodium dodecyl sulfate 5.6 ± 0.4 mmol Lâ1 and 4.3 ± 0.4 mmol Lâ1 were obtained in 1 mmol Lâ1 and 5 mmol Lâ1 phosphate buffer (pH 7.0), respectively. The values were comparable to those obtained from conductometric measurements under the same conditions (7.0 ± 0.1 mmol Lâ1 and 5.2 ± 0.1 mmol Lâ1, respectively) and the difference was explained in accordance with theory of hemi-micelle formation.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Jitka SouÄková, Jana Skopalová, LukáÅ¡ Műller, Michaela VymÄtalÃková, Petr Barták,