Magnetic Particles

Coated Polystyrene Magnetic Particles
These magnetic particles are prepared by coating a layer of iron oxid and polystyrene onto the core of the particles. They are relativly uniform in size, spherical in shape and paramagnetic in nature. The paramagnetic nature of the particles allows them to be separated by using a magnet but the particles will resuspend easily when removed from the magnet. They will not retain any significant magnetism even after repeat exposure to strong magnetic field.These magnetic particles can be used for cell separation, affinity purification, DNA probe assays, magnetic particle EIA etc. The coated magnetic particles are prepared by covalent coupling, concentration is around 2 x 108 particles/ml, 0,02% sodium azide added..The Particles are supplied monodisperse in the described range, the actual size is depending on current lot.nr.

Magnetizable Nanoparticles and magnetizable microparticles, Dextran based
The magnetite content of the plain 20 nm, 50 nm and 100 nm magnetic particles is 35% (w/w).The magnetite content of 20 nm, 50 nm and 100 nm functionalized magnetic particles lies in the range of 55-85% (w/w) in dependence on the particle diameter and surface functionalization.The magnetic (crosslinked dextran) particles with a diameter of 300 nm and 500 nm have a magnetite content of 80-90% (w/w).20 nm, 50nm and 100nm particles can due to their small size only be separated by a "High Gradient magnetic Field" device ( HGMF ).

Magnetic Polystyrene Particles

Magnetizable Fluorescent Polystyrene Microparticles, supplied as 10mg/ml suspension

Magnetic Polystyrene Particles with terminal PEG- groups
These beads consists of magnetite in a polystyrene copolymerisate as organic matrix (density 1.2g/cm³). They include a final coating with terminal PEG-COOH or PEG-NH2 groups, which can be used for nonspecific or covalent binding of proteins, antibodies, DNA etc.The particles are monodisperse with low SD and a CV of less than 6%. The magnetisation is 3.0 emu/g beads (H=1.000 Oe)They are stable in aqueous buffers, methanol, ethanol, DMSO and are supplied as aqueous suspension.This type of magnetic beads can also be offered with coatings of avididin, streptavidin, protein A and albumin on request.

VariMag Separation Rack for Tubes
The VariMag Separator accomodates tubes from 1,5ml to 200 ml tissue culture bottle. It uses interchangable tube holders to secure different tube and bottle sizes. A set of three tube holders, smal-medium-large is included:smal: 4 x 1,5 ml and 4 x 10/12 x 75 mm tubes, 8 in totalmedium:two 15 ml or two 16 x 100 mm tubes, 4 in totallarge:two 200 ml tissue culture bottles directly without adapter.VaryMag-S is designed for smal scale use. It holds up to eight 1,5ml tubes, 5 ml cryo vials or 10/12 x 75mm tubes.

Magnetic Separation Racks for Microplates
The UltraMag and UltraMag-DW separator are designed to facilitate the washing of magnetic beads in the magnetic Particles Enzyme Immunoassay (MPEIA) using 96-well plates. The magnetic pegs of the separator fit between the wells underneath the 96-well plateIf the separator is loaded with the microplate into an appropriate reader, the particles stay out of the light beam passing through the bottom of the well and corresponding holes in the UltraMag separator.The difference in the magnetic plates is that MR-96 has the magnet located underneath the 96 well plate( see picture at right) while the MR-96-DW, has the magnets in between the wells of a 96 deep well plate.See picture below:
MR-96-DW
The MicroMag Separator is designed to fit to 96-well microplate with round-, flat or V-bottom. The magnetic strips on the separator will pull the particles to a corner of the well to facilicate the aspiration of supernatant during the washing

Magnetic Silica Particels, 6 µ mean diameter
These magnetic microparticels have a cluster size of 3-10 m with a mean diameter of 6 µ. They show a homogeneous distribution of magnetite in the silica matrix. They can be separated easily also in high viscous media by standard permanent magnets.
• Density is 2,25 g/ ccm
• Magnetisation is 6.0 emu/g particels (H= 1000 Oe)
• The beads are very stabel in aqueous buffers > 3.0, in organic solvents and can widestand high temperatures
• They are not stabel in hydrofluoric acid and strong basic media, e.g. 6 M NaOH
• The plain beads have a binding capacity of 5 -10 µg plasmid-DNA ( after 1 - 1,15 ml overnight bacteria culture)

The beads are also availabel in fluorescent green and red to combine separation and detection.
• Fluorescent green: Excitation 485 nm, Emission 510 nm
• Fluorescent red: Excitation 569 nm, Emission 585 nm

Magnetic Silica particles - a fast method for DNA/RNA purification and Protein separation
Separation techniques are goinig to be more and more important in biotechnology, to get on cost efective, simple, reproducable ways and by using automatisation systems. The large surface area of 50m2/g provides a high capacity to bind cells, bacteria, DNA/RNA, proteines or antibodies.These paramagnetic uniform non porous silica particles are with 80% magnetit content allow simple magnet separation. The are supolied in double destilled H2O, but can be offered in powder form on request.

main applications of the chemical modifications:
Silanol:DNA & RNA techniques, purification of genomic DNA, plasmid DNA, viral DNA or PCR products.
DNA/RNA bind to the silica beads under high salt conditions as 4 mol NaL or 5 mol GuSNC.
Silanol-ROB: especially developed for use of DNA/RNA separation in robotic systems.
Carboxyl: binding of bioactive substances by the Carbodiimide methode
Amino:binding of bioactive substances by the Carbodiimide methode
Cyanuric replaces Chloromethyl due to better binding characteristics
Streptavidin: biotin labeled molecules
Biotin:avidin/streptavidin labeled molecules

available on request: magnetic silica beads with Protein A andG, Oligo(dt), calf tymus DNA, Albumin and GaM (Fc).

Magnetic Silica particles - 1,5µ with different surfaces