Skip to main content
validation of biomagnetic separation processes, magnetic bead separation

The 2 ways you can demagnetize your Magnetic Bead Separation device

Since reproducibility over time is a highly desired trait when using biomagnetic separation, especially when used in the life sciences, it is important to consider all possible disruptions of consistency. Magnetic Bead separation devices use permanent magnets which maintain their properties over long periods of time.

Free PDF guide:  "Validation of Magnetic Bead Separation Processes" 

This post is about Magnetic Bead Separation and how to demagnetize Magnetic Bead Separation devices. If you are interested in this topic, and are willing to learn more about it, download our Free Guide The Starting Guide to Validate Magnetic Bead Separation Processes:

How can we demagnetize a moden Magnetic Bead Separation device?

Modern devices use a rare earth magnet: neodymium iron boron (NdFeB), because of its outstanding properties. While NdFeB magnets are considered permanent, (i.e. have constant and consistent properties), even these magnets have potential limitations over time and can very slowly lose their magnetic properties.

It is important to consider these potential limitations and learn how to minimize them.  Therefore, we have listed below the two major ways that human interaction can demagnetize a Magnetic Bead Separator so that these conditions can be avoided.

1- High magnetic fields

If your magnet is exposed to a magnetic field of greater than 1 Tesla (which is greater than 20,000 times the Earth’s magnetic field), this can demagnetize a neodymium iron boron magnet.

The only device in a life science setting that can do this sort of damage is a hospital grade MRI.

2- High temperatures

If one heats a magnet high enough, a point can be reached which causes thermal agitation to overcome magnetic interactions, thus demagnetizing the material. An NdFeB magnet heated at 80ºC or more, over a minimal period of 30 years will cause the magnet to lose 0.5% of its magnetic force.

Therefore, if you work with your samples at 20 – 40ºC, you are fine. You will not be doing any damage to your Magnetic Bead Separator. However, do not put your device into an autoclave! If you DO need to autoclave your Magnetic Bead Separator, there are other magnets you can use in your device that will survive higher temperatures.

Because of this, an NdFeB magnet is a highly stable magnet and should have highly desired consistent properties when reproducibility issues are at stake.

Magnetic bead separation devices can be demagnetized with high temperatures

If you found this article interesting and want to get a deeper insight in the topic of Magnetic Bead Separation, make sure to check these articles from our blog:

Dr. Lluís Martínez

New Call to action

Lluis M. Martínez | SEPMAG Chief Scientific Officer

Founder of SEPMAG, Lluis holds a PhD in Magnetic Materials by the UAB. He has conducted research at German and Spanish academic institutions. Having worked in companies in Ireland, USA and Spain, he has more than 20 years of experience applying magnetic materials and sensors to industrial products and processes. He has filed several international patents on the field and co-authored more than 20 scientific papers, most of them on the subject of magnetic particle movement.

Leave a Reply