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Anion exchange columns

strong and weak anion exchange

Suitable for biomolecules like proteins, peptides, DNA, RNA

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Product information

Ion exchange chromatography is an analytical method relying on the interaction of ion-charges between the surface of proteins and the surface of the packing material. Packing materials with a positive surface charge are called “anion exchangers” and those with a negative surface charge are called “cation exchangers”.

A strong anion exchange resin with a quaternary ammonium functional group is packed into the IEC QA-825 column. This columncan be used at a wider pH range because the pKa of the ion exchange base is 11.7.

IEC QA-825

  • Suitable for analyzing relatively high molecular weight compounds: proteins, peptides, DNA, and RNA

  • Usable in a wide pH range from pH 2 to 12

  • QA-825 fulfills USP L23 requirements

 

A weak anion exchange resin with a diethylaminoethyl (DEAE) functional group is packed into IEC DEAE-825 and Asahipak ES-502N columns. These columns are suitable for the separation of acidic proteins because the pKa of the ion exchanger is about 7.8.

IEC DEAE-825

  • Suitable for analyzing relatively high molecular weight compounds: proteins, peptides, DNA, and RNA

  • Usable in a wide pH range from pH 2 to 12

 

Asahipak ES-502N 7C

  • Suitable for analyzing relatively high molecular weight compounds: proteins, peptides, DNA, and RNA

  • Usable in a wide pH range from pH 2 to 12

  • Compared to IEC series columns, polyvinyl alcohol is used as base material and this offers different separation pattern

  • Low hydrophobic interaction of proteins allows analysis under mild conditions

 


Obtaining some information about the isoelectric point (pI) of proteins is useful for selecting suitable analytical conditions. Proteins consist of amino acids, and are amphoteric compounds, so there is pH at which the total sum of electrical charges becomes zero in the solution. That pH is called isoelectric point (pI). Around the pI, the electrical charge on the surface of proteins is neutralized and such proteins cannot easily adsorb on the surface of the packing material. In some cases, proteins precipitate around the pI, a phenomenon known as “isoelectric precipitation”. In order to adsorb the target protein, the pH of the eluent must be adjusted at more than 1.0 pH unit from pI. When the pH is more acidic than the pI, a cation exchanger should be used, and when the pH is more alkaline than the pI, an anion exchanger should be selected.

Product overview

Product code
Product name
Separation
Functional group
Gel material
Plates per column
Particle size
Pore size
Size (ID x length)
Housing material
F6110011
IEC QA-825
Ion Exchange
Quaternary ammonium
Polyhydroxy-methacrylate
≥ 2,000
12 µm