Other Thematic Submissions Requested About Applications of Magnetic Particles

Collection of Paper Submissions: Applications of magnetic particles in biomedical imaging, diagnostics and therapies

In recent years, great strides have been made in the fabrication of inorganic nanoparticles of desired size, shape and crystal structure. This synthetic control enables researchers to precisely manipulate the physical and chemical properties of nanomaterials, opening up new technological opportunities. As a result, inorganic nanoparticles are now being extensively explored for applications including precision imaging, diagnostics and biomedical therapies. Magnetic nanoparticles have unique practical opportunities in this regard. They can be manipulated by external fields to move, and to generate heat as well as being used as tracer materials for imaging and sensing.

Submit papers here: https://www.nature.com/collections/dhahfijacf

Deadline for submission: December 31, 2025

This special collection is edited by Anna Bakenecker, Inge Herrmann & Jing Zhong.

Report from the European School on Magnetism (ESM) 2025

The European School on Magnetism (ESM) 2025 took place from 30 June to 11 July 2025 in Liege, Belgium. The focus was on "Topology for Low-Energy Spintronics". As in previous years, the school's mission was to train and connect around 100 young scientists and engineers in magnetism, primarily PhD students and early-career researchers.

Drawing on experience with hybrid formats, ESM 2025 combined shorter lectures with extended tutorials and practical sessions, allowing participants to personalize their learning experience. This new approach was very well received, with participants highlighting the value of hands-on sessions and increased interaction with lecturers.

Social aspects also made a strong contribution to the success of ESM 2025:

• The ice-breaking evening and room-sharing arrangements facilitated networking and integration among participants.

• The Discord platform was praised for its ease of use and efficiency in coordinating social and academic activities.

Visit the EMA website for more information and recordings of ESM 2025 lectures. Slides from all previous schools (recordings since 2020) are available in ESM repository.

The next ESM 2026 will be held in Uppsala, Sweden. ESM 2026 will be chaired locally by Prof. Biplab Sanyal and Dr. Heike Herper.

Magnetic Particles Can Fight Stubborn Biofilms

When bacteria infect our bodies, they sometimes form sticky mats of sugars and proteins called biofilms to protect themselves. This viscous layer makes it difficult for antibiotics and immune cells to reach the invading microbes, rendering usual therapies less effective. Researchers, led by Li Zhang at the Chinese University of Hong Kong and Ben Wang at Shenzhen University, demonstrated that magnet-driven, light-activated microrobots can cut through this goo and fight biofilms in the sinuses of animals (Sci. Robot. 2025, DOI: 10.1126/scirobotics.adt0720).

Other scientists have previously proposed using microrobots, which are smaller than 1 mm, to target and disrupt biofilm formations, either mechanically or by delivering chemicals that kill bacteria. But biofilms in the sinuses present a unique challenge for microrobots because our natural immune response to a sinus infection produces a viscous pus that’s hard to get through.

The researchers got around this sinus buildup problem by designing their bots to stir up the goo. External magnets placed near the sinuses guide the robots to align into chains and form spinning swarms that create a mechanical force to break up both thick sinus fluids and biofilms.

The microrobots themselves have a magnetic core and a shell of copper-doped bismuth oxoiodide (BiOI), a light-sensitive material. When exposed to visible light delivered by an optical fiber guided magnetically into the sinuses, electrons in the BiOI jump to a higher energy level, leaving behind positively charged holes. In this electron-hole pair, the excited electrons can react with oxygen to form superoxide radicals, while the holes react with water to produce hydroxyl radicals—both species are toxic to bacteria.

When the BiOI absorbs light, it also heats up, which further breaks down mucus and biofilms.

In live rabbit sinuses, the robots cut through thick mucus and destroyed bacterial biofilms without damaging healthy tissue. In pig sinus tissue, which is more anatomically like human sinus tissue, the microrobots also destroyed biofilms, with only 3% of bacteria surviving the treatment.

New Nanomedicine: Microflowers Map Capillaries

Tiny, flower-shaped devices made of copper phosphate were coated with iron nanoparticles and a fluorescent dye, then introduced into the fine vasculature of mice ears. This enabled a team from ETH Zurich to steer the microflowers using magnets and to track them with a combination of light and ultrasound. “It enables us to visualise small blood vessels in detail”, says Daniil Nozdriukhin, the lead author. In future, these flowers could also be used to deliver drugs precisely to their target.

D. Nozdriukhin et al.: Multifunctional Microflowers for Precise Optoacoustic Localization and Intravascular Magnetic Actuation In Vivo. Advanced Healthcare Materials (2025)

Permanent Magnets Explained

A recent Chemical and Engineering News "Periodic Graphics" explained permanent magnets. Just as a refresher, have a  look at it here, where chemical educator and compound interest blogger Andy Brunning explores the materials science of permanent magnets: https://cen.acs.org/materials/Periodic-Graphics-Permanent-magnets-explained/103/web/2025/0

Cancellation of the "Frontiers in Magnetic Particles Conference 2025"

Regrettably, Jenny Andrew and Thompson Mefford had to cancel the 2025 "Frontiers in Magnetic Particles" conference in Telluride, Colorado, due to unforeseen circumstances, including ongoing travel restrictions and disruptions in funding.

The organizers appreciate the interest and enthusiasm shown by the potential attendees, sponsors, and speakers. They will be exploring alternative options for sharing the knowledge and insights that were planned for this event.

If you have already registered, the Telluride Science and Research Center will be reaching out shortly regarding next steps on processing refunds.

Magnetic Nanoparticles Transport Drugs Deep Into Tumors With Magnet's Help

Drugs and other treatments can be quite effective at killing cancer cells, yet many fall short as they struggle to penetrate deep into solid tumors due to physical barriers within the tissue. But in a recent study published in ACS Nano, Andrew Tsourkas, Zhiliang Cheng et al. may have found a way to pull them through.

This team of bioengineers at the University of Pennsylvania transported therapeutic magnetic nanoparticles into the depths of tumors by tugging at them with an external magnetic device, based on 8 Halbach arrays. Working in a mouse model of triple-negative breast cancer, the researchers used their approach to slow tumor growth far more than treatment with nanoparticles not exposed to a magnetic field. In addition, the nanoparticles contained a Ce6 coating which could be activated with a red laser. The authors tracked the growth of the tumors over 16 days and then, at the end of the experiment, placed tumors under a microscope to search for the particles. They reported that tumors treated with the new system contained 3.7 times as many particles, which penetrated 3.5 times deeper, compared with tumors treated with the previous device, which ultimately slowed their growth significantly compared to all other groups.

Review About Dual--Frequency Magnetic Particle Spectroscopy

Hans-Jochim Krause and Ulrich Engelmann wrote a new review published in Advanced Science (https://doi.org/10.1002/advs.202416838). The fundamentals of frequency mixing magnetic detection (FMMD) as a special case of magnetic particle spectroscopy (MPS) are reviewed, elaborating its functional principle that enables a large dynamic range of detection of MNP. The latest applications of FMMD in nanomaterials characterization as well as diagnostic and therapeutic biomedicine are highlighted: analysis of the phase of the FMMD signal characterizes the magnetic relaxation of MNP, allowing to determine hydrodynamic size and binding state. Variation of excitation amplitudes or magnetic offset fields enables determining the size distribution of the particles’ magnetic cores. This permits multiplex detection of polydisperse MNP in magnetic immunoassays, realized successfully for various biomolecular targets such as viruses, bacteria, proteins, and toxins. A portable magnetic reader enables portable immunodetection at point-of-care. Future applications toward theranostics are summarized and elaborated.