+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Effect of initial voltage ramp on separation efficiency in non-aqueous capillary electrophoresis with ethanol as background electrolyte solvent

, : Effect of initial voltage ramp on separation efficiency in non-aqueous capillary electrophoresis with ethanol as background electrolyte solvent. Journal of Chromatography. A 1068(1): 107-114

Band broadening at high electric field strengths in capillary electrophoresis (CE), especially in wide capillaries, is often attributed to radial temperature gradients in the interior of the capillary caused by Joule heating. In some cases, however, a major cause of the lower separation efficiency could be the abrupt application of high electric field strength. We show that, with ethanol as background electrolyte solvent, initial abrupt voltage application introduces band broadening, which is especially pronounced in wider capillaries at high electric field and ionic strengths. With an appropriate initial voltage ramp this effect can be avoided. The effect of different voltage ramp up times on the separation efficiency of some anionic analytes was investigated with 50, 75 and 100 microm I.D. capillaries at field strengths of 1000-2000 V cm(-1). The results suggest that the band broadening associated with abrupt voltage application is of thermal origin and probably related to thermal volume expansion of the sample and background electrolyte solutions. The plate numbers calculated with a plate height model were in good agreement with the experimental values when a sufficiently long voltage ramp was employed. The dispersion due to axial temperature gradients was found to be very small under the experimental conditions used.


PMID: 15844548

Other references

Lanyon J.W., 1979: The wood anatomy of 3 proteaceous timbers placospermum coriaceum dilobeia thouarsii and garnieria spathulaefolia. A study was made of the wood anatomy of 3 unusual members of the Proteaceae, i.e., P. coriaceum, D. thouarsii and G. spathulaefolia. The anatomy of each is described and their relationship with other members of the family is discussed.

Wang, W-Qun.; Robertson, C.; Dhalla, A.K.; Belardinelli, L., 2008: Antitorsadogenic effects of ({+/-})-N-(2,6-dimethyl-phenyl)-(4[2-hydroxy-3-(2-methoxyphenoxy)propyl]-1-piperazine (ranolazine) in anesthetized rabbits. Ranolazine [Ranexa; (+/-)-N-(2,6-dimethyl-phenyl)-(4[2-hydroxy-3-(2-methoxyphenoxy)propyl]-1-piperazine] is novel anti-ischemic agent that has been shown to inhibit late I(Na) and I(Kr) and to have antiarrhythmic effects in various preclinical in...

Mio, K.; Csoka, A.B.; Maibach, H.I.; Stern, R., 1999: Inter-alpha-inhibitor, identified as a serum inhibitor of hyaluronidase, is also an acute phase substance. Molecular Biology of the Cell 10(SUPPL ): 151a, Nov

Solum, T.; Sjöberg, N.O., 1980: Antenatal cardiotocography and intrauterine death. The purpose of the present study was to elucidate the reliability of antenatal cardiotocography (CTG) in predicting fetal death. During a 4-year period, 1 455 patients eith risk pregnancies have been routinely monitored with antenatal CTG. The tot...

Fytizas ; E. ; Mourikis, P.A., 1972: Some observations on the survival of Dacus oleae Gmel. in the adult stage. Laboratory studies in Greece showed that adults of Dacus oleae (Gmel.) given a diet of sugar, hydrolysed yeast and water lived considerably longer than did those deprived of the yeast. Survival among adults of both sexes caged together was lower t...

Fulk, G.W.; Cyert, L.A.; Parker, D.E., 1999: A clinical trial of bifocals in children Myopia progression after two years. IOVS 40(4): S694, March 15

Shackley, S.E.; King, P.E., 1977: The reproductive cycle and its control; frequency of spawning and fecundity in Blennius pholis L. Spawning in Blennius pholis L. is seasonal occurring from March to July in the population of the South Gower beaches. There is evidence that both temperature and daylength regulate the reproductive cycle. Cyclical changes in the ovary during the r...

Mittendorf, W.F., 1887: Transmitted Pulsation at the Fundus Oculi. Transactions of the American Ophthalmological Society 4: 491-494

Matty, J.M.; Tomson, M.B., 1988: Effect of multiple precipitation inhibitors on calcium carbonate nucleation. Understanding the factors which affect the precipitation of calcium carbonate is important to the study of most natural waters. The effect of blends of precipitation inhibitors on calcium carbonate nucleation is investigated via a new test apparat...

Massaad, J.; Crawford, K., 2008: Double aortic arch and nasogastric tubes: a fatal combination. Double aortic arch is a common form of complete vascular ring that encircles both the trachea and the esophagus, and presents with various respiratory and esophageal symptoms, usually in the pediatric population. We present a case of double aortic...