See all Posts
Illustration of magnet and 96-well plate beads for article on magnetic bead separation.
Published On: April 6th, 2021

Magnetic bead separation makes nucleic acid and protein purification more effective and easier to automate. With advancements in lab technology and reduced costs, magnetic separation has become a leading technique for sample purification. Read on below to know more about magnetic bead separators.

How Does a Magnetic Bead Separator Work?

A magnetic bead separator uses superparamagnetic beads or particles. They are made up of tiny particles of iron oxides ranging from 20 nm to a few µm with superparamagnetic properties, meaning that they exhibit magnetic properties only in the presence of an external magnetic field. Their small size enables them to stay separated when needed, along with any material they’re bound to.

When using magnetic beads for cell separation, the beads have a coating that can reversibly bind with nucleic acids by adjusting the buffer condition.

The magnetic bead separator then applies an external magnetic field to attract the beads to the tube’s outer edge containing the sample. This separates the beads from the suspension and immobilizes them with the target DNA.

The sample is then washed to remove the unwanted suspension, and an elution buffer is added to the tube. This elution buffer releases the DNA from the magnetic beads and is removed from the tube or microplate well by pipetting. This produces a purified DNA sample, ready for downstream assays or quantitation. Applications that benefit from using a magnetic bead separator include immunoprecipitation, cell isolation, nucleic acid isolation, and other downstream processes from PCR to ELISA.

Advantages of Using a Magnetic Bead Separator

There are numerous advantages of using a magnetic bead separator compared to other non-magnetic separation processes. Here are some of them.

  • It prevents sample loss. Since magnetic bead separation doesn’t involve centrifugation or filtration instead of a bead separation, you won’t lose any of the bound nucleic acids during the wash step. Therefore, you can ensure you get a consistent, high-purity sample, increasing reproducibility and accuracy.
  • It provides efficient extraction. Because they are non-porous, magnetic beads are suitable for cell separation. As the sample doesn’t enter the beads, there’s no sample wastage leading to an efficient extraction.
  • They have a high binding capacity. Magnetic beads have a small size which translates to a large surface area. This gives them a high binding capacity.
  • Magnetic bead separators are convenient to use. Setting up a magnetic bead separator is quick as you don’t need to perform pre-clearing and incubation for immunoprecipitation. This is possible as the beads are non-porous and are less prone to non-specific binding of undesired molecules. You also don’t need to perform centrifugation as the buffer can be safely removed without washing away the beads’ molecules.

Automating Magnetic Bead Separation in The Lab

Modern magnetic bead separator stations come in compact sizes that can be integrated with other lab instruments and robots to create a semi or fully automated system. Below are some components that you can integrate with your magnetic bead separator when designing an automated extraction system.

  • Liquid Handler. An automated pipettor like the SOLO Liquid Handler is essential in an automated magnetic bead separator to dispense reagents. To get the most out of your system, consider the number of pipette head tips and microplate configuration it supports.
  • Microplate Handling System. A microplate stacker or microplate handling robot allow you to automatically store and transport plates to instruments in your lab. These robots can simultaneously operate on multiple plates, ensuring optimum efficiency.
  • Thermocycler. PCR is an important process in many labs and integrating your magnetic bead separator, thermocycler, pipettor, and microplate handler can create a truly hands-off workflow in the lab.
  • Lab Automation Software. Lab automation software controls all instruments in an automated workcell. With it, you can program the workflows involving your magnetic bead separator down to the reagent volume and process times. Consider software that allows you to design custom protocols and is compatible with your instruments.

Magnetic bead separation is a quick and effective method of extracting DNA and other molecules. By integrating your magnetic bead separator with other instruments in an automated workcell, you can further increase your lab efficiency.

Contact Hudson Robotics to learn more about magnetic separation and our other solutions.