highest purity means clean, sharp separations
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analytical filter papers special grades for chromatography and electrophoresis
Purity and sharpness of separation are two reasons why many laboratories specify S&S in chromatography work. The outstanding purity of product and extreme degree of uniformity re sponsible for such unusually clear and consistent results, come from using the finest raws obtainable, then processing with unusual skill and judgement. Add to this the quality control technicians who guard S&S quality and repu tation. Every single S&S batch is tested by actual analysis. Should there be even the slightest question as to ash content, or variation in physical or chemical properties, the batch is discarded. S&S Filter Papers for Chromatography A wide selection of specially selected grades for chromatography and elec trophoresis is available. Chemists may choose from a variety of character istics—as to absorption, thickness, wet-strength, etc. There are both ash low, as well as acid washed "ash free" grades which contain less than 0.007% ash. Selectacel® Ion Exchange Cellulose Powders* For use either in batch work or in chromatographic columns. Remarkable separations are produced with ionic and colloidal materials of high molecu lar weight, such as enzymes, proteins, hormones, lipids and nucleic acids. Even such presumably pure materials as hemoglobin can be separated into several fractions. Selectacel TLC Ion Exchange Cellulose Powders for Thin Layer Chromatography Superior, extremely sharp separations can be produced—even of closely related substances. This is possible because of narrow particle size dis tribution, and the exceptional uniformity of the Selectacel ion exchange celluloses themselves with respect to substitution by the functional ion exchanging groups. S&S markets a broad line of high quality analytical filter papers, filtration specialties, chromatographic materials, including TLC powders; and mem brane filters. For free technical literature just mail the coupon.
FREE D A T A - N O OBLIGATION—TEAR O U T C O U P O N A N D M A I L Carl Schleicher & Schuell Co., Keene, New Hampshire, Dept. INS For highest quality S&S Analytical known
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I would like to have free S&S informative bulletins about the following: D Membrane Filters Π Analytical Filter Papers D Chromatography and Electro Π Ion Exchange Celluloses phoresis Π Thin Layer Chromatography Π Sampler of Analytical Filter (including detailed instructions Papers (with chart of relative as to procedure) retention values) Name Company. Address... City
•Produced by Brown Company and exclusively packaged and [ distributed for laboratory use by Carl Schleicher & Schuell Co. ;
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Photographs courtesy of Parke, Davis and Company
