Capillary electrophoresis equipment

Hilmi, A., J.H.T. Luong, and A.-L. Nguyen. 1999. Development of electrokinetic capillary electrophoresis equipped with amperometric detection for analysis of explosive compounds. Anal. Chem. 71 873-878. 

Santos, B., Simonet, B.M., Rios, A. and Valcarcel, M. (2006) Automatic sample preparation in commercial capillary-electrophoresis equipment. TRAC, 25 (10), 968-976. 

Almeda S, Nozal L, Arce L, Valcarcel M. Direct determination of chlorophenols present in liquid samples by using a supported liquid membrane coupled in-line with capillary electrophoresis equipment. A a/C/j/m Acta 2007 587 97-103. 

The coupling of an FI manifold to capillary electrophoresis equipment enables sample preparation prior to introduction into the capillary. FI preconcentration by liquid-solid steps, dialysis, and liquid-liquid separations have been developed in a precapillary position. 

Hilmi, A., et al. "Development of Electrokinetic Capillary Electrophoresis Equipped with Amperometric Detection for Analysis of Erqrlosive Compoimds." Analytical Chemistry 71 (1999), 873-879. 

We have developed the method for quantitative analysis of urinary albumin with CE. A capillary electrophoresis systems Nanophor 01 (Institute of Analytical Instmmentation, Russian Academy of Sciences, Saint-Petersburg) equipped with a UV-detector was used to determine analyte. Separation was achieved using 45 cmx30 p.m I.D. fused silica capillary column with UV-detection at 214 nm. 

A capillary electrophoresis systems CAPEE 103R ( Eumex Etd, Saint-Petersburg) equipped with a UV-detector was used to separate and quantify analytes. 

High performance capillary electrophoresis was introduced originally as an analytical tool. Now that instruments are equipped with automated fraction collection, however, capillary electrophoresis can be used for micropreparative collection of individual peaks separated from a mixture. Using the fraction collection feature, nanomolar amounts of solute such as proteins, peptides, oligonucleotides can be collected in amounts sufficient for microsequencing. An intersample washing procedure and use of well-formed capillaries aid in the prevention of artifacts.44... 

In the previously described electrophoretic methods, the capillary was filled with electrolytes only. Another mode of operation in capillary electrophoresis involves filling the capillary with gel or viscous polymer solutions. If desired, a column can be packed with particles and equipped with a frit.68 This mode of analysis has been favorably used for the size determination of biologically important polymers, such as DNA, proteins, and polysaccharides. The most frequently used polymers in capillary gel electrophoresis are cross-linked or linear polyacrylamide,69 cellulose derivatives,70-75 agarose,76 78 and polyethylene glycols. 

Miniaturized columns have provided a decisive advantage in speed. Uracil, phenol, and benzyl alcohol were separated in 20 seconds by CEC in an 18 mm column with a propyl reversed phase.29 A19 cm electrophoretic channel was etched into a glass wafer, filled with a y-cyclodextrin buffer, and used to resolve chiral amino acids from a meteorite in 4 minutes.30 A 6 cm channel equipped with a syringe pump to automate sample derivatization was used to separate amino acids modified with fluorescein isothiocyanate.31 Nanovials have been used to perform tryptic digests on the 15 nL scale for subsequent separation on capillary Electrophoresis.32 A microcolumn has also been used to generate fractions representing time-points of digestion from a 40 pL sample.33 A disposable nanoelectrospray emitter has been... 

The basic components of an LC-NMR system are some form of chromatographic instrument and an NMR spectrometer equipped with a flow-probe, as shown in Fig. 19.17. In terms of the chromatography of choice, there are many examples in the literature of a wide array of separation instruments employed, from SFC to capillary electrophoresis (CE) [87,88]. By far the most common method (not necessarily the best choice from a separation point of view) of achieving the desired separation is through HPLC. There are many commercial... 

Capillary electrophoresis with diode array detection. Ultraviolet spectra (190-350 nm) were recorded after separation of fractions III, IV, and V-2 by capillary electrophoresis with diode array detection (CE-DAD) in 30 mM phosphoric acid buffer pH 2.3 and pH 7.2. Separations were carried out with a Hewlett-Packard 3D GE equipped with a diode array detector. Samples were introduced under pressure (30 mbar, 10 sec) into a fused silica capillary (effecfive lengfh 8 cm, total 64.5 cm, ID 50 pm, OD 375 pm) followed by separafion af 30 kV. 

Capacity Another consideration is the capacity of the laboratory to handle the work involved in a given method. For example, a capillary electrophoresis method would not be chosen if the laboratory does not have the instrument. It is also important to look at such factors as other equipment needed, the supplies needed, etc., or whether the laboratory can follow the required health and safety regulations, etc. Sometimes there may not be enough manpower or equipment to handle the sample work load. In that case, storage and refrigeration can also be a problem. 

Every analyst who has access to CE equipment and ESI-MS may take this new alternative into consideration when appropriate. When is it appropriate If an analytical problem can be solved using affinity capillary electrophoresis and a more universal and specific detection or structural information is required than is accessible with the help of conventional UV diode array detectors, consider ACE/MS. 

For analytical equipment, qualification is broken down into four areas design qualification (DQ), installation qualification (IQ), operational qualification (OQ), and performance verification (PV) [2,3]. In this chapter we focus on the operational qualification of a capillary electrophoresis instrument. The tests used in the operational qualification are often used in the routine performance verification as... 

The method of complete electrolysis is also important in elucidating the mechanism of an electrode reaction. Usually, the substance under study is completely electrolyzed at a controlled potential and the products are identified and determined by appropriate methods, such as gas chromatography (GC), high-performance liquid chromatography (HPLC), and capillary electrophoresis. In the GC method, the products are often identified and determined by the standard addition method. If the standard addition method is not applicable, however, other identification/determination techniques such as GC-MS should be used. The HPLC method is convenient when the product is thermally unstable or difficult to vaporize. HPLC instruments equipped with a high-sensitivity UV detector are the most popular, but a more sophisticated system like LC-MS may also be employed. In some cases, the products are separated from the solvent-supporting electrolyte system by such processes as vaporization, extraction and precipitation. If the products need to be collected separately, a preparative chromatographic method is use-... 

Capillary electrophoresis is not used as much as liquid chromatography. Advantages of electrophoresis relative to chromatography include (1) higher resolution, (2) low waste production, and (3) generally simpler equipment. Drawbacks of electrophoresis include (1) higher limits of detection, (2) run-to-run irreproducibility of migration times, (3) insolubility of some analytes in common electrolyte solutions, and (4) inability to scale up to a preparative separation. 

Capillary electrophoresis is a commercially available technique, and has been integrated with most automated lab equipment such as autosamplers. 

Finally, equipment for assaying and analyzing the preparations is needed. Most such equipment is fairly standard in biochemical laboratories and includes spectrophotometers, scintillation counters, analytical gel and capillary electrophoresis apparatuses, immunoblot-ting materials, and immunochemical reagents. 

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