Electrophoretic profile

CE is applied to two major categories of quality release testing identity and impurity testing. Identification assays are intended to ensure the unique identity of an analyte in the sample. This is normally achieved by comparison of a property of the sample (e.g., spectrum, chromatographic behavior, chemical reactivity, etc.) to that of a reference standard. As shown in Figure 9, CZE can be used to determine identity for monoclonal antibodies and proteins based on their unique electrophoretic profile. 

Figure 1. Electrophoretic profiles ofglucan synthase fractions purified from red beet. Proteins were transferred to nitrocellulose and stained by colloidal gold followed by silver overlay. Lane 1, solubilized enzyme (CSGS) Lane 2, reconstituted glucan synthase (RCGS).

Figure 2. Electrophoretic profiles of glucan synthase fractions purified from celery. Proteins were transferred to nitrocellulose and stained by colloidal gold. Symbols PM, plasma membranes SOL, CHAPS-solubilized RC, reconstituted glucan synthase preparations. Plasma membranes were isolated by two-phase partitioning. Specific activities of the three membrane preparations were 398, 1355, and 626 nmol/min/mg, respectively. The low specific activity of RC relative to SOL may be a reflection of enzyme instability following the gel filtration step.

Major proteins of globule and serum membranes are immunochemi-cally identical (Nielsen and Bjerrum 1977), and electrophoretic profiles of the proteins from either membrane are similar (Kitchen 1974). The major quantitative difference is the presence of higher amounts of a protein of Mr 85,000 in serum membrane fractions. In summary, the information suggests that milk serum membranes are related, but not identical, to milk lipid globule and plasma membranes. 

The difficulty in establishing surrogate endpoints because in vitro tests often fail to correlate with meaningful clinical outcomes (e.g., a chromatograph or electrophoretic profile of a protein does not assure stability, reactivity or specificity of an immune globulin) ... 

Xu, B., etal. (2005). Two-dimensional electrophoretic profiling of normal human kidney glomerulus proteome and construction of an extensible markup language (XML)-based database. Proteomics 5, 1083-1096. 

A simple CZE method, using a borate buffer at pH 9.5 and UVD at 280 nm, was applied for analysis of Spanish red wines. Although the electrophoretic profile was similar for different wines, the quantitative analysis varied much between them. The following phenolic components were identified (—)-epicatechin (2), (+)-catechin (3), (—)-epigallocatechin (74), syringic acid (70), vanillic acid (38), gallic acid (8), protocatechuic... 

The simultaneous concurrence of equality in spectral and electrophoretic profiles, that is, each component is described by a unique dyad of vectors, leads to the so-called trilinearity. TrUinear data offer excellent possibilities for... 

Alternating Least Square Optimization. The optimization process starts the iterative calculations from the initial estimates (spectral or electrophoretic profiles) of species to be modeled. If spectra are used as an input, the conjugated peak profile contributions C can be calculated as follows ... 

Figure 4. Electrophoretic profile of supercoiled (S) and nicked (N) SV40 DNA incubated with trans-DDP (top) and cis-DDP (bottom) both at [DDP/DNA(N)]incubatcd = 10 for various times at 25 °C. The outermost lanes contain control (C) SV40 DNA after incubation for 0 min (left) and 24 h (right). Lanes 2-13 contain DNA reacted with trans-DDP or cis-DDP for times (left to right) of 0, 3, 10, 20, 30, 50, and 85 min and 2, 3, 6, 12, and 24 h. (Reproduced with permission from Ref. 15. Copyright 1982, Academic Press.)...

FIGURE 7 CaD-Sepharose affinity chromatography of heavy meromyosin. HMM (1.5 mg) was applied to a CaD affinity column equilibrated with buffer containing 20 mM Tris (pH 7.5), 0.5 mM DTT, 40 mM NaCl, and 0.2 mM CaC. The column was washed with the buffer, and at the point indicated by the arrow the bound protein was eluted with the same buffer containing 0.5 M NaCl. The inset shows the SDS gel electrophoretic profile of control HMM (lane 1) and HMM eluted from the column with 0.5 M NaCl (lane 2). Reprinted with permission from Biochemistry (32). Copyright 1993 American Chemical Society. 

Figure 7 Soy protein phosphorylation using cAMPdPK as a function of time (A) electrophoretic profile of the protein subunits (B) autoradiogram of the electrophoretic profile. (From Ref. 85. Reprinted by permission.)...

A variation of the above method is crossed immunoelectrophoresis with an intermediate gel. The first electrophoretic steps including plate preparations, running buffer and sample application are the same as with the conventional procedure of Laurell s. The modification with the intermediate gel has been worked out to find out which of the peaks appearing on the complex electrophoretic profile of serum... 

During preservation, even under optimum conditions, certain enzymes change their electrophoretic profile. It is possible that this results from interactions between the sulfydryl groups (SH) of some cysteine residues and the glutathione accumulated over the storage period. This effect may be... 

M., Bermejo, E., Zapardiel, A., and Chicharro, M. (2014) Classification of Spanish white wines using their electrophoretic profiles obtained by capillary zone electrophoresis with amperometric detection. Electrophoresis, 35, 1693-1700. 

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