Biotechnological and Biomedical Applications of Magnetically Stabilized and Fluidized Beds - Porous Media: Applications in Biological Systems and Biotechnology - page 474

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FIGURE 12.8
Experimental setup of a enzyme immobilized MSFB: 1—MSFB column, 2—
Recirculation tank, 3—Pump, 4—Rotameters, 5—Distributor, 6—Enzyme
immobilized magnetic particle bed, 7—Power supply, 8—Magnetic coil. (From
Webb et al. 1996.)

mainly due to the great eciency of another well-known competitive method:
anity chromatography. However, in situations where particulate solids are
present (mainly in the early stages of the separation/purification processes)
MSFB is the most effective existing method.
Protein purification/adsorption by MSFB depends on the possibility to
create porous nanomagnetic beads that are capable to adsorb the target
protein. These nanomagnetic beads may have a large spectrum of different
compositions, and more details of these types of particles, and how they are
manufactured and functionalized are given by Safarik and Safarikova (2004).
As previously stated, these nanomagnetic beads are formed by a ferromagnetic
core covered with a polymeric layer, which is then functionalized (polymers
possess a large variety of surface functional groups, which can be tailored to
be used in different kinds of applications [Turkmen et al. 2006]). Polymer
chains are then attached to the surface of the polymeric layer of the porous
nanomagnetic beads to form tentacle-type supports that enhance the protein
adsorption capability (Turkmen et al. 2006). These magnetic adsorbents are
then inserted in a MSFB setup, as in the example shown in Figure 12.9.
Several proteins are and have been purified by this method, as detailed by
Safarik and Safarikova (2004). As typical examples we may refer: cytochrome- c
adsorption (Turkmen et al. 2006), lysozyme adsorption (with the kind of beads
described above, or with dye-anity mPHEMA beads) (Tong and Sun 2003;
Basar et al. 2007), bovine serum albumin adsorption (Tanyolac and Ozdural
2000; Ding and Sun 2005), and horsehearth myoglobin (Seibert et al. 1998).

12.5.2.3 MSFB Chromatography

A technique called MSFB chromatography was initiated several decades ago
and it has recently reached a high eciency level. More recently, a novel