Kromasil® HPLC Bulk Packing Materials

Restek – Your One Source for Kromasil® Bulk Packing Materials

• The Kromasil® HPLC products you know and trust – available from Restek!
• Perfectly spherical, totally porous bulk silica products.
• Wide range of bonded phases and particle sizes.

HPLC grade silica materials differ greatly from one manufacturer to another. Factors that affect the selectivity of a silica substrate include the surface area and chemical purity of the substrate, the pore structure, and the pore diameter distribution. Kromasil® HPLC silica products consist of highly spherical, porous particles in sizes from 3.5µm to 16µm and larger. The surface properties of the silica have been optimized, including a narrow pore size distribution and well-defined pore structure. For chromatographic separations, this ensures higher efficiencies, smaller pressure drops, and excellent lot-to-lot reproducibility.

Kromasil® spherical silicas are produced using a sol-gel technique, which yields a mechanically strong particle with a large surface area (330m2/g for 100Å silica). Metal impurities are carefully monitored, as trace metals in the silica structure increase the surface acidity and can lead to tailing peaks for basic or chelating compounds. Typical metal content for Kromasil® silicas is shown in Table 1.

Table 1  Typical chemical purity for Kromasil® spherical silicas.
Metal	Content (ppm)
Na	<25
Al	<10
Fe	<10
Based on AAS or ICP measurements.

Kromasil® bulk packings are available from Restek in a wide range of particle sizes and bonded phases. For more information, please contact Restek technical service at support@restek.com, or by phone at 800-356-1688 or 814-353-1300, ext. 4.

Kromasil® Bulk Packings