Processing Catalog - EMD Chemicals

New Robust Tentacle Media
Tentacle surface technology, based on the grafting
of functionally substituted acrylamides to
the surface of porous particles, has now been
transferred to a novel hydrophilic vinyl polymer
resin. The resulting Fractoprep® ion exchange
media show excellent protein binding capacities
at high flow rates, with much improved mechanical
and chemical stability. The resins are extremely
resistant to sodium hydroxide treatment,
the most important clean-in-place step in almost
every production process and, in addition, pro-
Ion Exchange Chromatography on Fractogel® EMD Tentacle Resins
In ion exchange chromatography, charged molecules
are separated on column materials that
carry an opposite charge. The ionic groups of ion
exchange resins are covalently bound to the gel
matrix and are partially neutralized by counter
ions present in the buffer. Because proteins are
multivalent anions or cations, at low salt concentrations
they will bind to stationary phases
that carry the opposite charge. The binding is
strongly influenced by the pH of the buffer. For
efficient use of ion exchange chromatography, it
is important to operate at pH values where the
exchangers are mostly ionised and the biopolymers
have a net charge (Table 1). Excessively
high salt concentrations, however, cause
shielding of the charges on the protein surface
and effective binding of protein to an exchanger
can no longer take place. Once bound to the
matrix, biomolecules are in turn displaced by an
increasing salt gradient or pH changes. Proteins
with different net charges can be separated.
Desorption of proteins from the column begins
only with increasing salt concentrations or pH
changes, when the protein no longer binds. The
compounds that have a higher charge density are
bound more firmly to the column while the
others elute more rapidly. In contrast to strong
ion exchangers, which can be used over a wide
pH range, weak ion exchangers have changing
degrees of ionization depending on the pH. Thus,
the pH range over which you can use the ion
exchangers is limited by these properties., e.g.
Fractogel® EMD COO - can be used above pH 5,
Fractogel® EMD DEAE below pH 8.5. The weak
vide other features essential for application in
bio-pharmaceutical production. Due to their
excellent mechanical rigidity, Fractoprep® media
are easy to handle and can be packed in large
production columns without any problems. For a
complete list of references citing tentacle media
products, please visit our web-page. This list of
references includes papers using all the different
types of Fractogel® EMD and Fractoprep® media.
ion exchangers are used, in general, in situations
where the pH of the load is consistent and doesn't
change from run to run. Strong ion exchangers
that are charged regardless of pH are generally
used in production were the feed streams
sometimes change.
Recently, a new generation of Fractoprep®
tentacle media was launched. Fractoprep® beads
have a particle size range between 30 and 150 µm
and were designed for capture steps. The new
Fractoprep® ion exchangers provide high productivity
especially in the capture step. Large
pores enable a free diffusion of proteins into the
beads and allow high throughput at very low
back pressure. Three different types of ion
exchangers, Fractoprep® DEAE, Fractoprep®
TMAE and Fractoprep® SO 3 - , extend the product
range of the well-known Fractogel® tentacle
resins.
Product Operating range Capacity
Fractogel® EMD TMAE BSA 100 mg/ml
Fractogel® EMD TMAE Hicap pH 6-10 BSA 180 mg/ml
Fractoprep® TMAE BSA 130 mg/ml
Fractogel® EMD DEAE BSA 100 mg/ml
pH 6-8.5
Fractoprep® DEAE
BSA 130 mg/ml
Fractogel® EMD DMAE pH 6-8.5 BSA 100 mg/ml
–
Fractogel® EMD SO3
Lysozyme 130 mg/ml
Fractogel® EMD SE Hicap pH 4-8 Lysozyme 160 mg/ml
–
Fractoprep® SO3
Lysozyme 100 mg/ml
Fractogel® EMD COO –
Table 1
pH 5-8 Lysozyme 100 mg/ml
Amino Acids
Buffers
Benzonase®
Biochromatography
Process and Production
Chromatography
Preparative Columns
Biochemicals
Enzymes
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