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Capillary electrophoresis electropherogram

Electropherograms of a urine sample (8 ml) spiked with non-steroidal anti-inflammatory drugs (10 p-g/ml each) after direct CE analysis (b) and at-line SPE-CE (c). Peak identification is as follows I, ibuprofen N, naproxen K, ketoprofen P, flurbiprofen. Reprinted from Journal of Chromatography, 6 719, J. R. Veraait et al., At-line solid-phase exti action for capillary electrophoresis application to negatively charged solutes, pp. 199-208, copyright 1998, with permission from Elsevier Science. [Pg.287]

Capillary electrophoresis offers several useful methods for (i) fast, highly efficient separations of ionic species (ii) fast separations of macromolecules (biopolymers) and (iii) development of small volume separations-based sensors. The very low-solvent flow (l-10nL min-1) CE technique, which is capable of providing exceptional separation efficiencies, places great demands on injection, detection and the other processes involved. The total volume of the capillaries typically used in CE is a few microlitres. CE instrumentation must deliver nL volumes reproducibly every time. The peak width of an analyte obtained from an electropherogram depends not only on the bandwidth of the analyte in the capillary but also on the migration rate of the analyte. [Pg.273]

Muddiman D.C., Rockwood A.L., Gao Q., Severs J.C., Udseth H.R., and Smith R.D. (1995), Application of sequential paired covariance to capillary electrophoresis electrospray ionization time-of-flightmass spectrometry unraveling the signal from the noise in the electropherogram, Anal. Chem. 67, 4371. [Pg.271]

Figure 5. Presentation of the change in levels of several beef proteins identified by capillary electrophoresis (CE). Electropherograms are shown in the insert. Numbers refer to the identification or name assigned to each peak. Figure 5. Presentation of the change in levels of several beef proteins identified by capillary electrophoresis (CE). Electropherograms are shown in the insert. Numbers refer to the identification or name assigned to each peak.
Fig. 5.4.12a-d Electropherograms of pure standards containing nine BA conjugates at a concentration of 50 nmol/ml (a), a blank serum sample from a healthy subject (b), the same serum sample spiked with 50 nmol/ml of nine different BAs (c) and serum sample from a patient with chronic hepatitis infection (d) analyzed by the capillary electrophoresis technique. Ultraviolet absorbance detection at 195 nm (reprinted from [30])... [Pg.638]

Figure 26-29 (a) Amperometric detection with macroscopic working electrode at the outlet of the capillary, (b) Electropherogram of sugars separated in 0.1 M NaOH, in which OH groups are partially ionized, thereby turning the molecules into anions. [From J. Ye and R. P Baldwin, Amperometric Detection In CapHary Electrophoresis with Normal Size Bectrodes," Anal. Chem. 1993,65,3525.]... [Pg.614]

A capillary electrophoresis system is comparatively simple. The basic components (Fig. 6.1) include the power supply which provides the high voltage necessary for the separation, the capillary in which the separation takes place, the detector which determines the sensitivity of the separation, and the data acquisition system which records the electropherogram. Some instruments also perform fraction collection. The final electropherogram looks similar to a chromatogram obtained from HPLC. [Pg.185]

Replicate capillary electrophoresis runs were made in which a standard solution of s P-labeled ATP was injected Into the capillary. The results are shown in Tables IV, V, and VI. These tables list the migration time, peak area, residence time, and detector efficiency. Representative electropherograms corresponding to the three detector efficiency determinations and the conditions under which the separations were performed are shown in Figures 4,... [Pg.70]

Figure 15. Electropherogram illustrating the capillary electrophoresis separation of poly d(A) 40-60 mer sample, P-labeled at the 5 end. Detection was accomplished using the coincidence detector. The separation was accomplished using a polyacrylamide gel-filled capillary and a constant potential of 15 kV. The sample activity in this example was approximately 4800 DPM/nL. Figure 15. Electropherogram illustrating the capillary electrophoresis separation of poly d(A) 40-60 mer sample, P-labeled at the 5 end. Detection was accomplished using the coincidence detector. The separation was accomplished using a polyacrylamide gel-filled capillary and a constant potential of 15 kV. The sample activity in this example was approximately 4800 DPM/nL.
Capillary electrophoresis is a powerful separation technique. Hinton and Ames162 subjected BSA (1 mM) to capillary electrophoresis, incubating it alone or with gly-oxal (25 mM) in phosphate buffer (pH 7.5) at 37 °C for 14 d. Electropherograms of the < 5 kDa fractions from tryptic digests exhibited > 70 peaks with some unique to each sample. [Pg.50]

Figure 5 Ultrafast SNP analysis by primer extension and capillary electrophoresis. Upper panel electropherogram of the mutant homozygote (G-mutation) with the 19-mer primer peak and the 26-mer product Middle panel electropherogram of the wild type with the primer and the 35-mer product Lower panel electropherogram of the heterozygote with all three peaks (19-, 26-, and 35-mers). Conditions capillary, = 10 cm (effective) (L = 30 cm), i.d. 75 pm separation matrix and running buffer, 10% PVP (MW 1,300,000) in 1 xTBE applied voltage, 20 kV injection, 30 s/10 kV temperature, 30°C. (Reproduced with permission from Ref. 64.)... Figure 5 Ultrafast SNP analysis by primer extension and capillary electrophoresis. Upper panel electropherogram of the mutant homozygote (G-mutation) with the 19-mer primer peak and the 26-mer product Middle panel electropherogram of the wild type with the primer and the 35-mer product Lower panel electropherogram of the heterozygote with all three peaks (19-, 26-, and 35-mers). Conditions capillary, = 10 cm (effective) (L = 30 cm), i.d. 75 pm separation matrix and running buffer, 10% PVP (MW 1,300,000) in 1 xTBE applied voltage, 20 kV injection, 30 s/10 kV temperature, 30°C. (Reproduced with permission from Ref. 64.)...
Figure 13.9. Affinity capillary electrophoresis-UV-raass spectrometry of a 100-tetrapep-tide library screened for binding to vancomycin (104 fxM in the electrophoresis buffer), (a) The elution of peptides was monitored with UV absorbance during capillary electrophoresis, and the elution time irrieased with increasing affinity for vancomycin. (b) Positive ion electrospray mass spectrum with CID of the Tris adduct of the proton-ated peptide detected at —5 min in the electropherogram shown in a (Reproduced from Ref 52 by permission of the American Chemical ardety.)... Figure 13.9. Affinity capillary electrophoresis-UV-raass spectrometry of a 100-tetrapep-tide library screened for binding to vancomycin (104 fxM in the electrophoresis buffer), (a) The elution of peptides was monitored with UV absorbance during capillary electrophoresis, and the elution time irrieased with increasing affinity for vancomycin. (b) Positive ion electrospray mass spectrum with CID of the Tris adduct of the proton-ated peptide detected at —5 min in the electropherogram shown in a (Reproduced from Ref 52 by permission of the American Chemical ardety.)...
An off-line approach that is simple and useful for peptide/protein sequencing using 5-10 picomoles of material has been demonstrated. Peptide and protein samples were first separated by capillary electrophoresis. Selected peaks were fraction collected and analyzed by both nano-electrospray mass spectrometry and Edman sequencing. A standard peptide mixture, a tryptic-digested protein and intact proteins were used to illustrate this method. Successful fraction collection of each component required reproducible electropherograms, the ability to automatically switch the outlet buffer vessel and the ability to maintain electrophoretic integrity while eluting a peak of interest into a small outlet buffer... [Pg.45]

Fig. 15 Capillary electrophoresis-mass spectrometry profile of two peptides preconcentrated on-line prior to separation. (A) Electropherogram of neurotensin (1) and angiotensin (2), concentrated and purified by C-18 immobilized to porous beads and monitored at 195 nm after separation by CE. (B) Total ion-current electropherogram of the separated peptides. The experimental conditions were similar to those described in Ref. 120 for gonadotropin-releasing hormone. The limits of detection for the peptides were approximately 1 to 5 ng/mL, depending primarily on the quality of the analyte concentrator-microreactor. Fig. 15 Capillary electrophoresis-mass spectrometry profile of two peptides preconcentrated on-line prior to separation. (A) Electropherogram of neurotensin (1) and angiotensin (2), concentrated and purified by C-18 immobilized to porous beads and monitored at 195 nm after separation by CE. (B) Total ion-current electropherogram of the separated peptides. The experimental conditions were similar to those described in Ref. 120 for gonadotropin-releasing hormone. The limits of detection for the peptides were approximately 1 to 5 ng/mL, depending primarily on the quality of the analyte concentrator-microreactor.
The electropherogram shown in Figure 10.6 represent a separation of three peptides with corrected migration times on the x axis. The separation efficiencies averaged 10s plates per meter. Compared to capillary electrophoresis, lower field strength is employed in PMMA microchip to minimize the Joule heating effect. Nonetheless, separations still occurred in far less time on the chip because of the short channel and generated comparable separation efficiencies. [Pg.249]

Figure 3.33 Electropherogram (A) and chromatogram (B) corresponding to a fortified drinking water sample analysed with both SPE with NACE and SPE with HPLC methods (Eive hundred milliliters aliquot of sample fortified at 0.50 ig/L for each triazine and polar metabolite. Reprinted from Journal of Chromatography A. Carabias-Martinez, R, et ai, Comparison of a non-aqueous capillary electrophoresis method with high performance liquid chromatography for the determination of herbicides and metabolites in water samples, 22(l-2), 194-201, Copyright 2006 with permission from Eisevied ). Figure 3.33 Electropherogram (A) and chromatogram (B) corresponding to a fortified drinking water sample analysed with both SPE with NACE and SPE with HPLC methods (Eive hundred milliliters aliquot of sample fortified at 0.50 ig/L for each triazine and polar metabolite. Reprinted from Journal of Chromatography A. Carabias-Martinez, R, et ai, Comparison of a non-aqueous capillary electrophoresis method with high performance liquid chromatography for the determination of herbicides and metabolites in water samples, 22(l-2), 194-201, Copyright 2006 with permission from Eisevied ).
Figure 9.23 Electropherogram showing separation of alkali and alkaline earth metals and ammonium by capillary electrophoresis column and conditions as detailed in text. Peaks (1) NHj, (2) K+, (3) Ca +, (4) Na+, (5) Mg +, (6) Sr +, (7) Ba2+ and (8) Li+. (Reproduced by permission of Dionex UK Ltd.)... Figure 9.23 Electropherogram showing separation of alkali and alkaline earth metals and ammonium by capillary electrophoresis column and conditions as detailed in text. Peaks (1) NHj, (2) K+, (3) Ca +, (4) Na+, (5) Mg +, (6) Sr +, (7) Ba2+ and (8) Li+. (Reproduced by permission of Dionex UK Ltd.)...
The main challenge for CE detectors is the small diameter of the capillary and the small sample volumes encountered. Detection schemes employed for capillary electrophoresis include measurement of UV absorption, fluorescence and refractive index. Electrochemical signals and conductivity as well as radioactivity from radioisotopes have also been measured. The signals obtained are plotted against the migration time in the form of an electropherogram. In recent years, coupling of CE to a mass spectrometer (CE-MS) has been achieved. [Pg.73]


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