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IEC
IEC
introduction to TSKgel iEC COLUMNS
Tosoh Bioscience offers a broad line of high efficiency col-
umns for analysis and isolation of biomolecules by anion
and cation exchange chromatography. In either mode of
IEC the product line contains methacrylate and silica based
columns. Most of the available chemistries are offered in
analytical as well as semi-preparative formats. Particle
sizes range from 2.5 µm for fast analysis to 20 µm for pre-
parative purposes. Proteins, peptides, oligonucleotides and
nucleic acids are typical samples that are analyzed or iso-
lated on TSKgel IEC columns.
PACKING MATERIALS AND CHEMISTRIES
Methacrylate, silica and polysterene are used as matrices
for the TSKgel line of ion exchange columns. The base resins
are derivatized either with diethylaminoethyl (DEAE), qua-
ternary ammonium (Q), sulfopropyl (SP) or carboxymehtyl
(CM) functionalities to provide weak anion, strong anion,
strong cation and weak cation exchangers, respectively.
Columns from the silica-based TSKgel SW series are typi-
cally used in the separation of low molecular weight com
pounds such as pharmaceuticals, nucleotides or small pep-
tides.
The methacrylate backbone chemistry provides a robust,
hydrophilic particle that is suitable as a support for high
performance analytical and preparative separations of bio-
molecules. The G5000 PW base resin of the TSKgel 5PW
series is a spherical particle with a mean pore size of 100
nanometer (1.000 Angström).
TSKgel BioAssist columns are also based on methacrylate
particles with larger pores (400 nanometer for BioAssist Q
and 130 nanometer for BioAssist S) providing better access
to the functional groups for large proteins.
The methacrylate chemistry also forms the backbone of
non-porous resin columns such as the TSKgel NPR and
STAT series. Since rate-limiting pore diffusion is eliminated
with nonporous particles, analysis time is often reduced by
as much as 80% without loss in resolution. Also, recoveries
are routinely greater than 90%.
TSKgel STAT columns are the latest addition to the IEC col-
umn line. An innovative bonding chemistry results in col-
umns that show a reasonable sample capacity while tra-
ditional non-porous resins usually show limited capacity
due to lower surface area. Specific application needs are
addressed by offering various column formats and particle
sizes.
For special applications polystyrene based columns are of-
fered as well. They are most suitable for analyzing small
molecular weight sugars, amino acids, individual nucleic
acids and small drug candidates. For detailed information
on these special columns please refer to the chromatogra-
phy catalog.
FEATURES
BENEFITS
BioAssist Columns
High capacity even for larger proteins (1 million Da)
Fewer runs to collect required sample amounts
Unique pore structure provides fast mass transfer
Sharper peaks improve analysis and isolation
Biocompatible PEEK column hardware
Less sample loss due to adsorption
Available in analytical and semi-prep formats
Easy scale-up
Polymer-Based Ion Exchange Columns
Methacrylate backbone
Mechanically and chemically stable (pH 2.0-12.0)
Withstands repeated cleaning with base, and use of
organic solvents, denaturants and surfactants
Large pore size (100 nm) (excl. limit for proteins ~
5,000,000 Da)
Use same column for most biopolymers
Non porous resin-based (STAT and NPR) columns
Fast QC analysis and process monitoring
Several columns available in 2 mm ID format
Reduced solvent consumption and analysis time
Silica-Based Ion Exchange Columns
Smaller pore size (2SW = 12.5 nm and 3SW = 25 nm)
Most suitable for analysing smaller MW samples such
as nucleotides, drug candidates, catecholamines and
small peptides or proteins
