Size exclusion chromatography standard

Standard enthalpy change in interaction chromatography Standard enthalpy change in size exclusion chromatography Standard entropy change... 

A series of polyvinylpyridine standards of different molecular weight were analyzed by size-exclusion chromatography, yielding the following results. 

DESIGN, PROPERTIES, AND TESTING OF POLYMER STANDARDS SERVICE SIZE EXCLUSION CHROMATOGRAPHY (SEC) COLUMNS AND OPTIMIZATION OF SEC SEPARATIONS... 

Size exclusion chromatography (SEC, also known as GPC and GFC) has become a very well accepted separation method since its introduction in the late-1950s by works of Porath and Flodin (1) and Moore (2). Polymers Standards Service (PSS) packings for SEC/SEC columns share this long-standing tradition as universal and stable sorbents for all types of polymer applications. In general, PSS SEC columns are filled with spherical, macroporous cross-linked, pressure-stable, and pH-resistant polymeric gels. 

Peptides are much more difficult to run by size exclusion chromatography than proteins because their solubilities differ greatly. Their shapes also vary from linear to semidefined. For a three peptide standard, Mant and Hodges... 

Generally, size exclusion chromatography is carried out using columns with an internal diameter of 7.8 mm. However, some SEC applications require the use of expensive solvents. For this purpose, size exclusion columns with a smaller internal diameter (4.6 mm) have been developed. Of course one should use proportionally lower flow rates with narrow-bore columns. If the standard column size uses a flow rate of 1 ml/min, then the smaller 4.6-mm columns should be used at a flow rate of 0.35 ml/min. This provides the same linear velocity as 1 ml/min on 7.8-mm columns. The decreased flow rate reduces solvent consumption and solvent disposal cost. The performance of the smaller diameter columns is not compromised if properly optimized instrumentation is used. 

This section discusses in detail the column types that are available for the size exclusion chromatography of both polar and nonpolar analytes. It first discusses the various columns available for standard nonaqueous size exclusion chromatography. It then reviews the columns available for general size exclusion chromatography using aqueous mobile phases. Finally, it examines the columns designed for size exclusion chromatography of proteins and peptides. 

Styragel columns are compatible with most solvents commonly used in size exclusion chromatography. Exceptions are found on both sides of the polarity scale the use of standard general-purpose Styragel columns with aliphatic hydrocarbons or with alcohols (except hexafluoroisopropanol) and water is generally not recommended. However, it is possible to pack columns in special solvents for special-purpose applications. The interested user should contact Waters for additional information. 

ASTM D 5296 - 92 (1994). Standard Test Method for Molecular Weight Averages and Moleeular Weight Distribution of Polystyrene by High Performance Size-Exclusion Chromatography. Annual Book of ASTM Standards, Vol.08.03, pp. 419-431. 

B. Broad Standard Size Exclusion Chromatography (SEC) Calibration... 

COMPARISON OF FOUR COMMERCIAL LINEAR AQUEOUS SIZE EXCLUSION COLUMNS AND FOUR SETS OF COMMERCIAL POLYETHYLENE OXIDE (PEO) STANDARDS FOR AQUEOUS SIZE EXCLUSION CHROMATOGRAPHY OF POLYVINYLPYRROLIDONE AND PEO... 

Gel permeation chromatography (GPC) or size exclusion chromatography (SEC) has been routinely used to estimate die molecular weight of die polymers. The molecular weight measured by GPC is relative to a polymer standard, typically polystyrene GPC is dius a relative method rather than an absolute one. For those polymers whose structure is very different from polystyrene, GPC molecular weight values could significantly differ from the real ones. In those cases, GPC values should only be regarded as a reference. 

The programs are described at length in the NBS publication NBS-IR 87-3669, System of Hardware and Software Developed for Size Exclusion Chromatography by B. Dickens and F.L. McCrackln, National Bureau of Standards, 1987, and available from NTIS under order number 88153697. Host of that report is concerned with interactive operation of the programs. 

At end, it is important to mention that calcium pectate gel beads were compared with calcium alginates gel beads for all entrapment uses [65, 66] in this work, the authors determined the pore size of the beads by size exclusion chromatography using dextran standards and other solutes. 

Figure 1. Size exclusion chromatography of Ru3(C0)i2 catalyzed polymerization of MeNH-[H2SiNMe]x-H as a function of time. Polystyrene standards used for calibration.

Determined by size exclusion chromatography with polystyrene standard in 1,2,4-trichlorobenzene dBranching density per 1000 carbons determined by H NMR... 

Molecular weight measurements were determined by size exclusion chromatography on a high pressure liquid chromatograph equipped with a differential refracto-meter. A Waters Styragel HR 5 i column set (106 104 500 A) was employed and calibrated with PS standards. THF was used as solvent at a flow rate of 1 ml/min. 

Novolac molecular weights were measured in THF at 35°C by high pressure size exclusion chromatography using a Waters Model 510 pump (flow rate=1.0 ml/min), 401 differential viscometer detector and a set of Dupont PSM 60 silanized columns. A universal calibration curve was obtained with a kit of 10 narrow molecular weight distribution, linear polystyrene standards from Toya Soda Company. Data acquisition and analysis were performed on an AT T 6312 computer using ASYST Unical 3.02 software supplied with the Viscotek instrument. 

Size-based analysis by CE provides similar information and comparable limits of detection to analysis by SDS-PAGE with Coomassie blue staining.120 129 The performance of both electrophoretic techniques for the analysis of polypeptides is far superior to size exclusion chromatography. Figure 9.7 shows the separation of SDS-complexed recombinant protein standards by CE. 

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