Beads
Sephadex®
EXTEND THE USEFULNESS OF GEL FILTRATION IN ANALYTICAL AND PREPARATIVE OPERATIONS Effluent delivery rates increased full order of magnitude Improvements in the production of SEPHADEX now permit this useful cross-linked dextran material to be supplied in the form of spherical beads. Substitution of the new beads for the irregularly shaped particles in which SEPHADEX was heretofore available (see Figure 1 ) results in far more uniform hydrodynamic condi tions within SEPHADEX columns. Tangible results? Flow rates are greatly improved with remaining good resolution. One of the most significant results of the introduction of the new beads is the extension of SEPHADEX gel filtra tion to production-scale preparative operations. As can be calculated from the lowest curve in Figure 2, a 10 cm. diameter column of coarse grade SEPHADEX G-25 under a head of 60
PHARMACIA LEADING IN DEXTRAN CHEMISTRY
cm. of water can deliver almost 19 liters/hour of effluent. We strongly suggest that laboratory workers acquaint their colleagues in semiworks and production engineer ing with the new beads of SEPHADEX. The use of the spherical particles could open entirely new avenues in unit operations.
Figure 2. The curves above depict pressuredrop/flow-rate functions for columns using a 50 cm bed of SEPHADEX G-25. For given hy drostatic heads, note that the new spherical beads give up to tenfold greater effluent de liveries. Analytical procedures are hastened and preparative operations are put within economically practical engineering ranges.
Available forms of new SEPHADEX beads Bed SEPHADEX Exclusion Limit (MW) Type
Figure 1. SEPHADEX was formerly supplied in the form of irregularly shaped particles as shown in top photograph. Now available in spherical beads as shown below, SEPHADEX facilitates packing of columns and greatly increases speed of operations.
For full informa tion on the use of SEPHADEX in gel filtration, send the coupon with your letterhead. (Inquiries outside the Western Hemisphere should be directed to PHARMACIA, Uppsala, Sweden.)
Grade
Size (microns)
Volume ml/g
*G-25
5,000
coarse fine
100-300 20-80
5
G-50
10,000
coarse fine
100-300 20-80
10
»G-75
50,000
one grade
40-120
12-15
G-100
100,000
one grade
40-120
15-20
G-200
200,000
one grade
40-120
30-40
*SEPHADEX G-25 (fine) and G-75 will not be available before October, 1963.
PHARMACIA FINE CHEMICALS, INC.
AC-12
D e p a r t m e n t BD, 501 Fifth A v e n u e , N e w York 17, N e w York I I "SEPHADEX": A Unique | | "SEPHADEX in Gel Fil- Γ~] C Gel Filtration L — '-"•* Substance for Modern ' t r a t i o n " : Theory and '""•"' L'iterature Chromatography Experimental Technique Abstract Cards Name Company Address
Circle No. 80 on Readers' Service Card
VOL. 35, NO. 13, DECEMBER 1963
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