Magnetic Separation in immunoassays

products-servicesNordic BioSite AB
June 8th 2015

 

Overview

Magnetic particle technology provides a powerful tool for the simple and efficient enrichment or depletion of specific cell populations. Nordic BioSite can supply a range of magnetic particles that are ideally adapted to the needs of immunoassay researchers.

Magnetic Separation in immunoassays

Immunoassays require highly specific and sensitive analytical techniques, largely due to the unique features of biomedical research antibodies that specifically target the analytes or antigens.

Biomedical researchers have increasingly turned to magnetic particle technology, using microscopic beads that are prepared by coating a layer of iron oxide and polystyrene onto polystyrene core particles. These particles measure between 1.0 µm and 10 µm.

Magnetic nanoparticles are even smaller (down to 200 nm or less) and they are excellent for immunoassays applications.

Their application in immunoassays facilitates techniques such as automation and development of simple, near-patient, diagnostic devices.

Nordic BioSite offers a range of magnetic particles coated with specific monoclonal antibodies for specific isolation of targeted analytes. They can also be coated with avidin, biotin, Protein A or other conjugates to suit the researcher’s experimental set-up.

Magnetic particle advantages

Use of Nordic BioSite’s specifically coated magnetic beads in immunoassays deliver clear benefits for researchers.

Specificity:
In most biological samples there is almost no magnetic material that could interfere with the measurements.
Speed:
The use of external magnets can radically speed up assays by bringing antibody‐coated particles to reaction surfaces in as few as four steps (see below). Further, simple, one step (or homogeneous), immunoassays are possible.
Purity:
External magnets can be used to remove excess label.
Replication:
Magnetic materials do not readily degrade so samples can be archived and re‐measured later.

Using Nordic BioSite magnetic particles

Magnetic particles can bind specific analytes, allowing researchers to work more easily with a sample that contains other analytes, besides the one that is of particular interest.

The technique can be used not only for proteins and smaller molecules, but also to separate out cells of interest in a crude sample, without using harsh methods such as lysis reagents.

A simple workflow for a common immunoassay separation exploiting the advantages of Nordic BioSite’s coated magnetic particles could have as few as four steps:

Step 1: Add coated magnetic particles to the sample containing a mixture of proteins, cells and molecules (depicted as green, yellow and star-shaped figures in the illustration). There is no need for pre-purification.

Step 2: The specificity of the particles via the coated antibody or protein means that the only component that will be bound to the particle is the analyte of interest (star-shaped figures).

Step 3: When the sample tube wall is subjected to magnetic force, only the magnetic beads and their attached analyte will be attracted. After some minutes, the accumulation of beans will be visible on the wall of the tube.

Step 4 (Wash Stage): Keeping the magnetic force applied, it is possible to pipette off or decant the residual sample (green and yellow figures) leaving only the analyte of interest in the tube.

Resources

Click on Magnetic Separation in immunoassays for more information.
Click on Nordic Biosite to contact the company directly.

Schematic of four-step analyte magnetic separation

Schematic of four-step analyte magnetic separation


Supplier Information
Supplier: Nordic Biosite
Address: Propellervägen 4A, 183 62 Täby, Sweden
Tel: +46 (0)8 544 433 40
Fax: +46 (0)8 756 94 90
Website: www.nordicbiosite.com