Sephadex fractionation ranges

Sephadex type Grade Dry bead diameter (/urn) Fractionation range peptides and proteins (g/mol) Fractionation range dextrans (g/mol) Swelling factor (ml/g dry Sephadex) Maximum operating pressure" (cm H,0) Permeability Ko Maximum linear velocity" (cm/hr) Swelling time (h) ... 

Dextrans of low molecular weight have also been fractionated by gel chromatography. Bremner and coworkers,67 in preparing (by alkaline degradation) dextrans of low molecular weight suitable for incorporation in the clinically important iron-dextran complex, fractionated their product on Sephadex G-50, with (O M sodium chloride as the eluant. Separate fractions, ranging in Mn (as determined by osmometry) from 1510 to 4860, were obtained in this way. 

Fractionation Range Sephadex G-50 has a fractionation range of 1500 to 30,000 daltons. Solute molecules within this range would be separated in a somewhat linear fashion. 

Equation 14.13 has been used to evaluate the hydrated radii of proteins by determining Km experimentally on three Sephadex gels, G-75 (fractionation range 3-80 kDa), G-100 (fractionation range 4-150 kDa) and G-200 (fractionation range 5-600 kDa). The results of these experiments are shown in Table 14.1. 

TABLE 2. Range of Sephadex and Sepharose Gels Manufactured by Pharmacia Showing Their Fractionation Range and Exclusion Limit... 

Sephadex Type Fractionation Range " for Peptides and Globular Proteins (MW) Bio-Gel Type Fractionation Range (MW)... 

Sephadex type Useftil fractionation range, mol wt in water, mL/g dry beads... 

Type Water regain (g/g dry Sephadex) delusion limit MoL Wt. Fraction range Mol. Wt. Limits... 

Procedure The chromatographic procedure may be carried out at room temperature using (a) a column (1 M x 25 mm) packed with a cross-linked dextran suitable for fractionation of globular proteins in the range of molecular weights from 5,000 to 350,000 (Sephadex G-150 is suitable), (b) mixed phosphate buffer pH 7.0 with azide as the mobile-phase with a flow rate of about 20 ml (4 ml per square centimetre) of column cross-sectional area) per hour, and (c) a detection wavelength of 280 nm. 

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