Temperature electrophoresis

Home-made electrophoresis machines have been designed for special applications that are beyond the operational range of commercial instruments. A high-temperature electrophoresis apparatuses is described in [259-262]. Illustrations of home-made apparatuses for measurements of the electrophoretic mobility of gas bubbles can be found in [263,264]. 

Polymers have come a long way from parkesine, celluloid and bakelite they have become functional as well as structural materials. Indeed, they have become both at the same time one novel use for polymers depends upon precision micro-embossing of polymers, with precise pressure and temperature control, for replicating electronic chips containing microchannels for capillary electrophoresis and for microfluidics devices or micro-optical components. 

A computer program was compiled to work out the ray-tracing of UV detector of high performance capillary electrophoresis at the investigation of 5 and 6 (98MI59). The capacity factor of 5 at different temperature and at different mobile phase compositions was experimentally determined in bonded-phase chromatography with ion suppression (98MI15). 

Small-angle X-ray scattering (SAXS), circular dichroism (CD), and UV spectroscopy at different temperatures were used to investigate the nature of calf-thymus DNA in aqueous solution, in the presence of [Me Sn] " (n = 1-3) species. The results demonstrate that the [MeSn(IV)] moiety does not influence the structure and conformation of the DNA double helix, and does not degrade DNA, as indicated by agarose gel electrophoresis. Inter alia, the radii of gyration, Rg, of the cross section of native calf-thymus DNA, determined by SAXS in aqueous solution in the presence of [Me Sn] " (n = 1-3) species are constant and independent of the nature and concentration of the [Me Sn] species. 

Figure 3. SDS-PAGE and in situ pectinase activity on pectin and polygalacturonic acid-agarose overlays of culture filtrates of Aspergillus niger N-402 (upper panel) and Aspergillus FP-180 (lower panel) at 2.5, 3.5, 5.5 and 6.5 pHi (Lanes a, b, c, and d, respectively). Electrophoresis on 10% acrylamide slab gel (14 X 8 cm) in the presence of SDS was according to Laemmli (6), run at 30 mA constant current for 2 hours. Crude cell-free samples were concentrated by lyophilization, dialyzed, boiled with sample buffer by 60 sec. and applied to each well. Polyacrylamide gel and overlays were incubated overnight with 0.17 acetate buffer at room temperature.

Polyacrylamide gel electrophoresis results suggest that p-LG undergoes a greater conformational loss as a fimction of extrusion temperature than a-LA, presumably due to intermolecular disulfide bond formation. Atomic force microscopy indicates that texturization results in a loss of secondary structure of aroimd 15%, total loss of globular structure at 78 °C, and conversion to a random coil at 100 °C (Qi and Onwulata, 2011). Moisture has a small effect on whey protein texturization, whereas temperature has the largest effect. Extrusion at or above 75 °C leads to a uniform densely packed polymeric product with no secondary structural elements (mostly a-helix) remaining (Qi and Onwulata, 2011). 

Reciprocally, the growth on single C source significantly decreases the bacterial diversity. For example, in the rhizosphere soil of potato, a dramatic reduction in the number of ribotypes was found by temperature gradient gel electrophoresis (TGGE) after 48 h of incubation with single C source substrate in Biolog microplate wells (I46). 

G. Muyzer and K. Smalla, Application of denaturing gradient gel electrophoresis (DGGE) and temperature gradient gel electrophoresis (TGGE) in microbial ecology. Antonie Van Leeuwenhoek 73 127 (1998). 

M. E. Lacey, A. G. Webb, J. V. Sweedler 2000, (Monitoring temperature changes in capillary electrophoresis with nanoli-ter-volume NMR thermometry), Anal. Chem. 72(20), 4991. 

Nelson, R. J., Paulus, A., Cohen, A. S., Guttman, A., and Karger, B. L., Use of Peltier thermoelectric devices to control column temperature in high-performance capillary electrophoresis, /. Chromatogr., 480, 111, 1989. 

A. Gerstner, Z. Csapo, M. Sasvari-Szekely, and A. Guttman, Ultrathin sodium dodecyl sulfate gel electrophoresis of proteins Effect of gel composition and temperature on the separation of sodium dodecyl sulfate-protein complexes, Electrophoresis, 21, 834 (2000). 

FIGURE 16.2 Representative base peak electropherograms from CZE runs of RPLC fractions, (a) Fraction 15 (5 peptide identifications) and (b) fraction 20 (19 peptide identifications). Column, bare fused silica capillary, 60 cm x 180 pm ODx30pm i.d. separation voltage, 15 kV observed CZE current, 1.91 p.A running electrolyte, 200 mm acetic acid + 10% isopropanol temperature, 22°C injection time, 10 s at 2 psi ( 4 nL total injection volume) supplementary pressure, 2 psi flow rate, 25nL/min spray voltage, 1.5 kV (reprinted with permission from Electrophoresis). 

FIGURE 16.8 HPLC chromatogram of cytochrome c and myoglobin digest, using a 250 cm x 4.6 mm ODS C18 Vydac column and a linear mobile-phase gradient, 5-50% B, in 50 min. Buffer A was 0.1% TFA in water and buffer B was 0.1 TFA in acetonitrile. UV detection was carried out at 214 nm, at room temperature (reprinted with permission from Electrophoresis). 

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