Polyaspartic Acid-coated Silica - 2µm Particle Diameter

PolyCAT A™ is polyaspartic acid-coated silica. It is a weak cation-exchange (WCX) material. PolyCAT A™ is made through a unique process for attaching poly(aspartic acid) covalently to silica. Proteins elute from this polypeptide coating in sharp peaks with little tailing. Binding capacity and recovery are high.

PolyCAT A™ for Protein & Peptide Analysis
▪ Protein variants involving deamidation, PEGylation, position of attachment, desialylation, etc.
▪ Hemoglobin variant analysis
▪ Proteins with pI above 6.0 (5.0 in special cases)
▪ Monoclonal antibodies
▪ Histones

Since PolyCAT A™ is a weak cation-exchange (WCX) material, it is used at pH values above 4. A gradient to unbuffered acetic acid will uncharge PolyCAT A™, permitting the elution of proteins in a volatile solvent.

Peptides can be run on PolyCAT A™ if they contain at least two excess positive charges above pH 4. More weakly basic peptides, such as tryptic fragments, are not reliably retained and should be run on PolySULFOETHYL A™ at pH = 2.7 - 3.0.

For proteins larger than 20 KDa, we recommend the use of pore diameters of at least 1000 Å for optimal selectivity and efficiency. Our 3-µm material with 1000- or 1500-Å pores is the finest cation-exchanger available for protein separations.

Please contact us at for specific academic pricing.