Magnetic dextran nanoparticles ( -D and -D-spio)

are available with particle diameters of 130 nm, 250 nm and 500 nm for separation with a permanent magnet ( -D). Superparamagnetic dextran nanoparticles with particle diameters of 20 nm, 50 nm and 100 nm can not be separated with a conventional permanent magnet but in a high gradient magnetic field ( -D-spio).

Magnetic dextran nanoparticles ( -D):

  • are prepared via the core-shell method with a core of magnetite and a dextran shell,

  • consist of 75-80% (w/w) magnetite in a matrix of dextran (40.000 Da),

  • are designed with the surface functionalities OH (plain), NH2 and COOH for the covalent binding of proteins, antibodies or other molecules,

  • are available with covalently bound proteins (avidin, streptavidin, protein A, albumin) or other biomolecules (biotin, glutathion),

  • can be provided with covalently bound antibodies on request,

  • are offered with the nickel(II) chelator nitrilotriacetic acid (NTA) or ready to use with the corresponding nickel complex (Ni-NTA) for the binding of histidine labeled proteins,

  • are also suitable for the complexation of metal ions with covalently bound chelators on the particle surface (EDTA or DTPA),

  • are available with various hydrophilic surfaces (PEG 300, PEG-NH2 or PEG-COOH),

  • are available with negative surface potentials (e.g. COOH, SO3H).

Superparamagnetic dextran nanoparticles ( -D-spio):

  • are prepared by precipitation of iron oxide in the presence of dextran,

  • functionalized  -D-spio consist of about 55-85% (w/w) iron oxide in a matrix of dextran (40.000 Da) in dependence on the diameter and surface modification,

  • differ in the size of the iron oxide domains for different diameters,

  • are preferably applied for detection purposes in magnetic resonance imaging or in magneto-immuno assays,

  • show good specific power absorption rates for hyperthermia applications for a particle diameter of 100 nm,

  • are designed with the surface functionalities OH (plain), NH2 and COOH for the covalent binding of proteins, antibodies or other molecules,

  • are available with covalently bound proteins (avidin, streptavidin, protein A, albumin) or other biomolecules (e.g. biotin),

  • are available with various hydrophilic surfaces (PEG 300, PEG-NH2 or PEG-COOH),

  • are available with negative surface potentials (e.g. COOH, SO3H) - can be provided with covalently bound antibodies on request.