Size-exclusion chromatographic

Several wide-porous affinity and size-exclusion chromatographic supports were prepared by Ivanov, Zubov et al. by means of acylation of aminopropyl-glass supports by copolymers of N-vinyl pyrrolidone (N-VP,1) and acryloyl chloride (AC,2), M = 7700 and 35000 respectively [50, 51]. The copolymers prepared by free radical copolymerization contain their units almost in equimolar proportion, with high tendency to alternation expected from the copolymerization parameters (rj = 0.035, r2 = 0.15 [52]). Residual carbonyl chloride groups of the chemisorbed copolymer could be transformed to 2-hydroxyethylamides which were solely... 

Anionic pol5Tnerizations make the molecular weight standards that are used to calibrate size-exclusion chromatographs. Equation (13.38) predicts PD = 1.001 at In = 1000. Actual measurements give about 1.05. The difference is attributed to impurities in the feed that cause terminations and thus short chains. Also, the chromatograph has internal dispersion so that a truly monodisperse sample would show some spread. Even so, a PD of E05 is extremely narrow by pol5Tner standards. This does not mean it is narrow in an... 

The validity of a practical method of direct viscosity calculation from size exclusion chromatographic analysis is demonstrated. The method is convenient to use and is not limited by the availability of narrow MWD standards. It is possible to accurately measure polymer Mark-Houwink constants using the suggested broad standard SEC-[n] and SEC-MW calibration procedure. 

Herman, D. P, Field, L. R., and Abbott, S., The size-exclusion chromatographic behavior of synthetic water-soluble polymers on diol bonded phase supports, /. Chromatogr. Sci., 19, 470, 1981. 

Brown, R. S., Hausler, D. W., Taylor, L. T., and Carter, R. C., Fourier transform infrared spectrometric detection in size-exclusion chromatographic separation of polar synfuel material, Anal. Chem., 53, 197, 1981. 

Wyatt, P. J., Hicks, D. L., Jackson, C., and Wyatt, G. K., Absolute gel permeation chromatographic determination of molecular weight and sizes. Part 2. Incorporation of gel permeation chromatography-size exclusion chromatographic measurements, Am. Lab., 20, 108, 1988. 

Viel, G.T., Yang, Q., Lundahl, P, Ensing, K., and de Zeeuw, R. A., Size-exclusion chromatographic reconstitution of the bovine brain benzodiazepine receptor. Effects of lipid environment on the binding characteristics, /. Chromatogr. A, 776, 101, 1997... 

Vander Heyden, Y., Hartmann, C., Massart, D.L., Hollands, A.M.J., Nuyten, P. and Schoenmakers, R, Ruggedness testing of a size-exclusion chromatographic assay for low molecular-mass polymers, /. Chromatogr. A, 756,89,1996. 

Inverse Size Exclusion Chromatographic (ISEC) Analysis of Solvent Wetted Polymer Supports... 

Figure 3 shows typical size exclusion chromatographs (SEC) of PMMA-/)-PS-/)-PMMA and multiblock copolymer (PMMA-Z)-PS)n.[35] The polydispersity index (Mw/Mn) of the two... 

When a size-exclusion chromatograph is calibrated correctly, one can know the molecular weight of a polymer just based on the time it takes to pass, or elute... 

A New Stand-Alone Capillary Viscometer Used as a Continuous Size Exclusion Chromatographic Detector... 

The automation of the SEC/Viscometer detector system is achieved by interfacing the DRI and viscosity detectors to a microcomputer for real time data acquisition. The raw data subsequently are transferred to a minicomputer (DEC PDP-11/44) for storage and data reduction. The automated data acquisition and analysis system for the size exclusion chromatograph with multiple detectors used in this study have been described previously.(23)... 

On-line size exclusion chromatographic (SEC) analyses were performed with a Waters Model 401 differential refractometer (DR), a Waters Model 480 ultraviolet (UV) variable wavelength spectrophotometer and a Foxboro Miran lA infrared (IR) photometer, equipped with a zinc selenide ultramicro flowcell of 1.5 mm nominal pathlength and 4.5 /xl volume, purchased from the same supplier. A set of ten Mycrostyra-gel (Waters Associates) columns, regenerated by Analytical Sciences Inc. (ASI) and of nominal porosities 100, 500 (two) 10 (two), 10 (three), 10 and lO X, in the order given and a mobile phase flow rate of 1 ml/min was used. The column set had a specific resolution of 19.7 in 1,4-dioxane, as determined by the method of Yau(2). 

Although the mechanism of SEC separation is controlled by linear molecular size as well as other parameters, the separation pattern is very reproducible. Considering all the molecular parameters responsible for the size exclusion chromatographic separation pattern and the known separation patterns of a number of compounds, it is possible to predict the retention volume of a compound of known strucure. Based on the same principle the retention volume gives information on the structure of the molecule. 

High-Performance Size-Exclusion Chromatographic Separations... 

Nonier, M.F. et al., Application of off-line size-exclusion chromatographic fractionation-matrix assisted laser desorption ionization time of flight mass spectrometry for proanthocyanidin characterization, J. Chromatogr. A, 1033, 291, 2004. 

This harmonious outcome from a simple procedure has far-reaching implications. That the species appearing at the void volume in aqueous 35% dioxane from Sephadex LH20 are associated is readily confirmed by the corresponding size-exclusion chromatographic profiles from a 106A pore-size... 

Yau et al.f used polystyrene samples of known molecular weight in tetrahydrofuran to calibrate the retention volume of a size-exclusion chromatograph. They obtained the following results ... 

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