Black polyethylene paramagnetic microspheres are now available in wide selection of particle sizes ranging from 10 micron to 1.4 millimeters. The particles are supplied in dry powder form. No solvents are used in the manufacturing process. Black paramagnetic polymer microspheres have a strong response to magnetic fields and can be manipulated with a magnet. Highly opaque particles with maximum hiding power.
Paramagnetic microspheres have the ability to increase in magnetization with an applied magnetic field and loose their magnetism when the field is removed. Neither hysteresis nor residual magnetization is observed and that provides the end use two very practical advantages:
- When the filed is removed, the microspheres demagnetize and re-disperse easily. This property allows efficient washing steps, low background and good reproducibility.
- The behavior of the microspheres is always the same whatever the magnetization cycles may be. Such behavior is a key point for automated instrument.
According to Wikipedia, paramagnetic materials have a small, positive susceptibility to magnetic fields. These materials are slightly attracted by a magnetic field and the material does not retain the magnetic properties when the external field is removed. Paramagnetic properties are due to the presence of some unpaired electrons, and from the realignment of the electron paths caused by the external magnetic field.
Encyclopedia Britanica defines paramagnetism as a kind of magnetism characteristic of materials weakly attracted by a strong magnet, named and extensively investigated by the British scientist Michael Faraday beginning in 1845. Most elements and some compounds are paramagnetic. Strong paramagnetism (not to be confused with the ferromagnetism of the elements iron, cobalt, nickel, and other alloys) is exhibited by compounds containing iron, palladium, platinum, and the rare-earth elements.
Paramagnetic microparticles are used in numerous applications where they can be manipulated with a magnet, observed and cleaned-up for reuse.
- Solid Phase Immunoassays
- Bacteria Detection
- High Throughput screening
- Rapid Tests
- Cell Sorting
- Nucleic Acids Technology