Microvehicles to Navigate Blood Vessels Upstream

Researchers led by ETH Zurich Professors Daniel Ahmed and Brad Nelson recently developed microvehicles that are small enough to navigate our blood vessels and can be propelled against a fluid flow using ultrasound. To achieve this, the researchers used magnetic beads made of iron oxide and a polymer with a diameter of 3 micrometers, and studied their behavior in a thin glasstube, which was similar in size to blood vessels in a tumor. The team then employed a magnetic field to induce the particles to cluster into a swarm, before using ultrasound to guide the cluster close to the wall of the tube. Finally, the researchers switched to a rotating magnetic field to propel the microbeads against the flow. Future applications include microsurgery, precisely delivering cancer drugs to tumors and transferring drugs from blood vessels into the tissues of the brain.

Check out the details here, with movie:  https://www.nature.com/articles/s42256-020-00275-x

Ultrafast Terahertz Magnetometry Could Enable Heat-Free Magnetism Control

Physicists have precisely measured the ultrafast change in a magnetic state in materials by observing the emission of terahertz (THz) radiation that accompanies such a change in magnetization. An international research team that included scientists from Bielefeld University, Uppsala University, the University of Strasbourg, the University of Shanghai for Science and Technology, Max Planck Institute for Polymer Research, ETH Zürich, and the Free University Berlin developed and tested the ultrafast magnetometry method.

The work could pave the way for spintronic research and technologies based on a purely acoustic and, where possible, heat-free, ultrafast control of magnetism. 

This principle states that a change in the magnetization of a material must result in an emission of electromagnetic radiation that will contain complete information on this change. If the magnetization in a material changes on a picosecond timescale, the emitted radiation will belong to the THz frequency range. This radiation, known as magnetic dipole emission, is weak and can be easily obscured by light emission that has originated elsewhere.

For more information, go here.

Special JMMM Issue Available - Scientific and Clinical Applications of Magnetic Carriers

While the 2020 meeting could not take place, you still had the opportunity of submitting a magnetic particle related article for a special JMMM issue, as we have done after all recent meetings. Twenty-five original articles are now available at this link. Get a coffee and some cake, and look through these interesting articles, they are well worth it!

And thank you Silvio Dutz and Maciej Zborowski for being the editor for this special issue.

www.sciencedirect.com/journal/journal-of-magnetism-and-magnetic-materials/special-issue/10L1Q3Q882M

European School on Magnetism (ESM) Open for Enrollment

The next session of the European School on Magnetism (ESM) is scheduled to take place in Cluj-Napoca, Romania, 6-17 Sep 2021. It will be organized in a mixed format, on-site and on-line. This shall allow all to participate whatever their wish or ability to travel at the time, and also beyond the onsite hosting capabilities for the waiting list. Nevertheless, we feel ready to turn it fully on-line if sanitary conditions requested it.

As with previous sessions of ESM, the 2021 School aims at providing a thorough insight into magnetism through a broad series of fundamental lectures, and to address a specific topic of current interest in more detail. The topic chosen for the 2021 School is: “From fundamental properties of matter to magnetic materials and applications”. We intend to cover modern aspects of bulk and layered materials, both about their fundamentals and their applications.

The School is addressed mainly at PhD students and post-docs, both experimentalists and theoreticians. It will consist of approximately 40 hours of lectures, student projects conducted in small groups, practicals and tutorials, open question sessions (5-10h), and free access to a library on magnetism. Attendees will be able to present their own work during poster sessions. The detailed program is available from the web site: http://magnetism.eu/school/2021/program.

Request for participation to the school opens today. Potential attendees are expected to provide, along with their application form, a motivation letter and, for PhD students and post-docs, a recommendation letter from their supervisor.  For more details, check out this flyer here.  

Embracing defects and disorder in magnetic nanoparticles: the emergence of defect-engineering as a new approach to optimize particle properties

To improve the performance of magnetic nanoparticles for biomedical applications, single-crystalline and defect-free nanoparticles have thus far been aspired. However, in several recent studies, defect-rich nanoparticles outperform their defect-free counterparts for example in magnetic hyperthermia and magnetic particle imaging. In the progress report “Embracing defects and disorder”, an overview on the state of the art of design and characterization of defects and resulting spin disorder in magnetic nanoparticles is presented with a focus on iron oxide nanoparticles.

The authors Aidin Lak, Sabrina Disch & Philipp Bender emphasize the beneficial impact of defects and disorder on intracellular magnetic hyperthermia performance of magnetic nanoparticles for drug delivery and cancer therapy. This report illustrates that defect-engineering in iron oxide nanoparticles emerges to become an alternative approach to tailor their magnetic properties for biomedicine, as it is already common practice in established systems such as semiconductors and emerging fields including perovskite solar cells. Additionally, the authors offer their perspectives and thoughts on how to deliberately induce defects in iron oxide nanoparticles and their potential implications for magnetic tracers to monitor cell therapy and immunotherapy by magnetic particle imaging.

This forward-looking progress report can be found on Lak, A., Disch, S., Bender, P., Embracing Defects and Disorder in Magnetic Nanoparticles. Adv. Sci. 2021, 2002682. https://doi.org/10.1002/advs.202002682

Info About the Next IWMPI Meeting

The International Workshop on Magnetic Particle Imaging, IWMPI, will be skipped in 2021 and held next in March 2022. The conference is currently planned as a face-to-face event. However, if the pandemic situation would not allow that, then it would again be a virtual meeting, as the IWMPI 2020.

The online meeting IWMPI 2020 had a total of almost 1000 participants who watched the livestream. The contributions in the Supplement to the International Journal of Magnetic Particle Imaging IJMPI (Vol 6 No 2 Suppl 1 (2020): Int J Mag Part Imag) are widely read and have good download numbers. Most talks were recorded and are included in the new MPI Media Library. While you have to register for the library, it is free of charge.

Magnetic hyperthermia therapy for glioblastoma

The Department of Neurosurgery at the Icahn School of Medicine at Mount Sinai has received at the beginning of 2020 more than $10 million in federal funding for several projects focusing on brain tumor research. Dr. Hadjipanayis is the lead investigator in the $3.4 million National Institutes of Health (NIH)-funded study to examine the effects of MHT when used in conjunction with chemoradiation to treat glioblastoma, a devastating brain cancer that almost always relapses because therapy-resistant cancer cells infiltrate the body at the tumor's margin. The study is expected to last five years and will be conducted in close partnership with Robert Ivkov, PhD, MSc, and his team at Johns Hopkins University, who developed the novel magnetic nanoparticles the studies will use. The grant involves a pilot study at Johns Hopkins treating dogs that have spontaneously developed glioblastoma tumors.

"These are powerful magnetic nanoparticles that we deliver directly into glioblastoma tumors by convection-enhanced delivery," said Dr. Hadjipanayis. "We then apply a safe, alternating external magnetic field that oscillates the nanoparticles, which generates heat that destroys the tumor. Multiple treatments can be performed since the nanoparticles persist in glioblastoma tumors. When used in conjunction with radiation and chemotherapy, we expect this treatment will lead to improved outcomes."

Robert Ivkov and co-workers published recently a cool study in this area, about the immunotherapy of cancer with magnetic nanoparticles. Check it out here.

Webinar by the Society for Thermal Medicine

On November 15, 2020, the Society for Thermal Medicine organized a webinar with 3 speakers. The theme was

Arousing Tumor and Systemic Immunity with Magnetic Nanomedicine.

If you want to check it out, go to the recorded session video HERE. Jeff Bulte gave a very nice overview and the history of in vivo Imaging of Dendritic Cells Using Magnetovaccination. Preethi Korangath from the Robert Ivkov lab followed and discussed how the systemic exposure of SPIOs stimulates immune resonses to inhibit tumor growth in mouse models of breast cancer. Excellent work.