Spend more of your time getting results... and less time getting ready.

NEW MALLIMCKRODT CHROMATOGRAPHIC PRODUCTS CUT TIME-WASTING "KITCHEN WORK" If you think chromatography is fast now, wait until you try the new Mallinckrodt products. They all come from the same silicic acid production stream that brings you Mallinckrodt Silicic Acid AR 100—the classic sorbent for column chromatography. But our new products are specialists. They offer you wide choices of physical, chemical and pH characteristics. They can eliminate platemaking, acid treating, sifting, mixing and other preparatory steps. For column chromatography, there are four new Mallinckrodt SilicAR™ sorbents classified by particle size.

Two fine-mesh sorbents for maximum Two coarser sorbents for the fast flow resolution in small columns. rates you want in large columns.

Notice the sharp bands. They result from close control of particle size and other physical properties. The sorbents are clear and white, too, because Mallinckrodt controls organic and inorganic impurities to the highest standards generally available in commercial sorbents. For TLC, try newv ready-to-use CHROMAR™ plates.

These are glass plates, just like the ones you make yourself. But CHROMAR plates are better, because they're more uniform. They'll take all standard sample sizes and methods of visualization. (If you still want to be a hold-out and make your own plates, choose one of the many Mallinckrodt SilicAR™ TLC sorbents. SilicARs

keep your chromatograms free of greyness on charred plates, contamination at the solvent front and other common troubles. They also have a bright white phosphor for sharper uv visualization.) For preliminary experiments in thin layer techniques, get the $39.75 CHROMAR kit.

The CHROMAR kit gets you into business fast. It has everything you need, except the solvent, to make plates and chromatograms; and it does the work of equipment costing seven times as much.

We've wrapped all these products (plus our new AluminAR™ activated alumina sorbent) into a new Mallinckrodt chromatography catalog. Send for your copy. Or call your Mallinckrodt distributor.

ν Write Dept. TLC

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