Today,our product portfolio of SuperParaMagnetic Microspheres is very large in terms of size, surface and ferrite content, and based on the well-renowned Estapor® Microspheres.
Our SuperParaMagnetic Microspheres provide powerful tools that help our customers in their success. Our Magnetic Microspheres have the appearance of a dark brown liquid. 

The Estapor® Magnetic Microspheres are, in fact, superparamagnetic materials. As shown in figure 1, the magnetization of the microspheres increases with the applied magnetic field and falls back to zero when the field is removed.

Neither hysteresis nor residual magnetization is observed and that has for the user two very pratical advantages:  

• When the filed is removed, the microspheres demagnetize and redisperse easily. This property allows efficient washing steps, low background and good reproducibility.
• The behaviour of the microspheres is always the same whatever he magnetization cycles may be. Such behaviour is a key point or automated ent.

 

 

Regular SuperParamagnetic Microspheres

 

Estapor® "M" microspheres, also called "Classical", are super-paramagnetic material, colloidally stable in the absence of amagnetic field. Exposed to a magnetic field, a total separation of the microspheres is achieved rapidly and completely. The iron oxide material is uniformly distributed in the polystyrene matrix. Our magnetic microspheres are currently used in various immunoassays including those running on automated immuno-analysers. They are also widely used in many biotechnological applications such as cell separation, nucleic acid purification or bacterial capture. Covalent coupling on the carboxyl or amino groups as well as passive adsorption can be carried out easily.

 

 

The main applications for Estapor© Magnetic Microspheres are the following:
 

• Chemiluminescent ImmunoAssays , Radio-ImmunoAssays,
• Cell Separation, Protein Purification, Immuno- Precipitation, Bacteria Detection,
• Immuno-chromatographic Assays,
• BioSensors and BioChips

 

 

The main benefits of our Classical "M" microspheres are:

• High Binding Capacity,
• Fast magnetic response time,
• Good colloidal stability
• Fast recovery of dispersion after attraction.

 

Small SuperParamagnetic Microspheres

The Small COOH-Modified SuperParamagnetic Estapor® Microspheres represent powerful solid phase for either automated or manual detection systems. Due to their small size, Microspheres from 300 to 500nm offer a very large specific surface area. This is a key point for developing an ultra-sensitive Immuno-Assay or for improving cell separation.
Our Small COOH-Modified Superparamagnetic Estapor Microspheres have shown exceptional properties in cell separation (cell-Microspheres complexes are directly analyzed on a Scan Cytometer, with no release of the Microspheres), in Immuno-Assays and in Qualitative and Quantitative Lateral Flow Assays.

 

 

Encapsulated SuperParamagnetic Microspheres

 

Encapsulated SuperParaMagnetic "EM" microspheres represent the state-ofthe-art in the field of magnetic carriers. Developed in 1992 in our laboratories, they are characterized by a core-shell structure. Iron oxide material, encapsulated by a film of polymer, does not interfere with the surface components. Our Encapsulated Microspheres are well known for their:

• Low Non Specific Binding
• High Binding Capacity
• Fast magnetic response time (Fig.4)
• Improved colloidal stability
• Fast recovery of dispersion after attraction