Electrophoretic apparatus

Fig. B.3 SDS-PAGE. (A) Different parts of the electrophoretic apparatus. (B) Running the SDS-PAGE.

The foregoing expression applies only to ions at a concentration approaching 0 and in a nonconductive solvent. Polyionic molecules are surrounded by a cloud of counterions that alter the effective electric field applied on the ions to be separated. This renders the previous expression a poor approximation of what really happens in an electrophoretic apparatus. 

The demand for these methods in peptide and protein separations in micro-quantity will increase. A new device which combines electrophoretic apparatus and a mass spectrometer or a sequencer may be developed in the near future. 

Gently fill the upper reservoir and connect the electrodes to the electrophoretic apparatus. Be sure that the anode is at the bottom. 6-33. Energize the power supply and adjust it to an output of 3 to 4 mA per gel tube (i.e., 21-28 mA total for a total of 7 tubes). DO NOT TOUCH THE SYSTEM BECAUSE A FATAL ELECTRICAL SHOCK MAY RESULT. Allow the system to operate in this manner for 15 to 20... 

Electrophoretic apparatus (Sub-Cell GT Agarose Gel Electrophoresis Systems, Bio-Rad) and power supply (PowerPac Basic Power Supply, Bio-Rad). 

The adsorption of natural polyelectrolytes (serum albumin-BSA) on kaolin suspensions as well as the complex formation with Na-chondroitin-6-sulfate (Na2Chs) was studied by Shimabayashi et al. by means of a microscope electrophoretic apparatus [11]. The iep of kaolin after covering with BSA was determined to be lower than that of BSA itself the zeta potential was positive at pH lower than 4.2. When the pH became higher than the iep, the zeta potential was reversed to negative values and decreased with pH. 

The photopolymerization of the spacer gel is effected, the comb is carefully removed (in order not to destroy the surface of the wells), the plates are mounted into the electrophoretic apparatus, and samples are placed in the wells. After having filled the electrode vessels with buffer the electrophoretic separation can be started. Diffusion staining and destaining of the gel is done after disassembling the plates. 

Fig. 6.28. (A) Preparative gel electrophoresis apparatus with step-wise elution. 1, Gel column 2, dialysis bag 3, 4, capillary tubes 5, 6, platinum electrodes 7, pump 8, monitoring system (UV). (B) Principle of the electrophoretic apparatus with intermittent elution.

Except for the electronic componentsr the electrophoretic apparatus was housed in a constant-temperature chamberr held at 37 C 1 with glove ports and windows through which the eyepieces of... 

The most successful method for separating enantiomers is to exploit the differential interactions that can take place as a result of their unique spatial orientation with those of a third enantiomer, which is introduced into the system to induct specific selectivity. The use of the special spatial arrangement of an enantiomer, to specifically interact with an enantiomeric reagent, and thus cause it to be selectively retained in a chromatographic or electrophoretic system, is currently the most direct and technically viable way to achieve the resolution of a wide variety of optical isomers. The extremely high efficiencies available from modern chromatographic and electrophoretic apparatus makes this approach by far the most effective for analytical purposes. The precise mechanism responsible for the selective retention of a specific enantiomer is very complex, but, nevertheless, can be explained on a rational basis and will be the subject of discussion in subsequent chapters. 

Figure 2 Cross-sectional view of an electrophoretic apparatus. A, Furnace B, electrophoresis chamber C, capillary D, tube supporting the capillary E, screw to adjust the height of the tube F, electrophoretic support medium G, heat-resistant glass plate H and H graphite electrodes I and I, reservoirs L, thermal couple M, heating wire, and N, insulating jacket. (Reproduced with permission from Alberti G, Allulli A, and Modugno G (1964) Journal of Chromatography 5 420-429.)...

Stock solutions were made either in pure deuterated methanol or in methanol containing 1% of cyclohexane (internal NMR reference). Various sample solutions ere then mixed in the NMR sample tube. The spectra were obtained using a Varian A-60 spectrometer (Varian Associates, Palo Alto, Calif.). Dioxane (8%) in benzene v as used as an external standard. The chemical shift is expressed cycles per second (cps) downfield. Electrophoresis experiments were measured in a Perkin-Elmer Model 238 electrophoretic apparatus. Both ascending and descending boundaries were observed. 

This case has acquired a great significance in the hands of A Tiselius S whose electrophoretic apparatus is now widely used to follow the electrophoresis of proteins in pure preparation and in mixtures (see below 7d) ... 

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