Nolan’s Notes: Our Spotlight on North America
Global Sourcing Spotlight: Building a Supply Chain That Bends, Not Breaks
Smart Automation: The Journey of a Component Through an SMT Factory
New Laws of Attraction: Scientists Print Magnetic Liquid Droplets
July 22, 2019 | Berkeley LabEstimated reading time: 6 minutes
All magnets, no matter how big or small, have a north pole and a south pole. Opposite poles are attracted to each other, while the same poles repel each other.
Through magnetometry measurements, the scientists found that when they placed a magnetic field by a droplet, all of the nanoparticles’ north-south poles, from the 70 billion iron-oxide nanoparticles floating around in the droplet to the 1 billion nanoparticles on the droplet’s surface, responded in unison, just like a solid magnet.
Key to this finding were the iron-oxide nanoparticles jamming tightly together at the droplet’s surface. With just 8 nanometers between each of the billion nanoparticles, together they created a solid surface around each liquid droplet.
Somehow, when the jammed nanoparticles on the surface are magnetized, they transfer this magnetic orientation to the particles swimming around in the core, and the entire droplet becomes permanently magnetic—just like a solid, Russell and Liu explained.
The researchers also found that the droplet’s magnetic properties were preserved even if they divided a droplet into smaller, thinner droplets about the size of a human hair, added Russell.
Among the magnetic droplets’ many amazing qualities, what stands out even more, Russell noted, is that they change shape to adapt to their surroundings. They morph from a sphere to a cylinder to a pancake, or a tube as thin as a strand of hair, or even to the shape of an octopus—all without losing their magnetic properties.
The droplets can also be tuned to switch between a magnetic mode and a nonmagnetic mode. And when their magnetic mode is switched on, their movements can be remotely controlled as directed by an external magnet, Russell added.
Liu and Russell plan to continue research at Berkeley Lab and other national labs to develop even more complex 3D-printed magnetic liquid structures, such as a liquid-printed artificial cell, or miniature robotics that move like a tiny propeller for noninvasive yet targeted delivery of drug therapies to diseased cells.
“What began as a curious observation ended up opening a new area of science,” said Liu. “It’s something all young researchers dream of, and I was lucky to have the chance to work with a great group of scientists supported by Berkeley Lab’s world-class user facilities to make it a reality,” said Liu.
Also contributing to the study were researchers from UC Santa Cruz, UC Berkeley, the WPI–Advanced Institute for Materials Research (WPI-AIMR) at Tohoku University, and Beijing University of Chemical Technology.
The magnetometry measurements were taken with assistance from Berkeley Lab Materials Sciences Division co-authors Peter Fischer, senior staff scientist; Frances Hellman, senior faculty scientist and professor of physics at UC Berkeley; Robert Streubel, postdoctoral fellow; Noah Kent, graduate student researcher and doctoral student at UC Santa Cruz; and Alejandro Ceballos, Berkeley Lab graduate student researcher and doctoral student at UC Berkeley.
Other co-authors are staff scientists Paul Ashby and Brett Helms, and postdoctoral researchers Yu Chai and Paul Kim, with Berkeley Lab’s Molecular Foundry; Yufeng Jiang, graduate student researcher in Berkeley Lab’s Materials Sciences Division; and Shaowei Shi and Dong Wang of Beijing University of Chemical Technology.
This work was supported by the DOE Office of Science and included research at the Molecular Foundry, a DOE Office of Science User Facility that specializes in nanoscale science.
Scientists at Berkeley Lab have made a new material that is both liquid and magnetic, opening the door to a new area of science in magnetic soft matter. Their findings could lead to a revolutionary class of printable liquid devices for a variety of applications from artificial cells that deliver targeted cancer therapies to flexible liquid robots that can change their shape to adapt to their surroundings. (Video credit: Marilyn Chung/Berkeley Lab; footage of droplets courtesy of Xubo Liu and Tom Russell/Berkeley Lab)
Share on:
Testimonial
"The I-Connect007 team is outstanding—kind, responsive, and a true marketing partner. Their design team created fresh, eye-catching ads, and their editorial support polished our content to let our brand shine. Thank you all! "
Sweeney Ng - CEE PCBSuggested Items
I-Connect007 Editor’s Choice: Five Must-Reads for the Week
05/01/2026 | Michelle Te, I-Connect007If it feels like the PCB industry is accelerating faster than ever, you’re not imagining it. From advanced materials driven by AI applications to renewed investment in domestic manufacturing—and the next generation stepping into critical roles—there’s a lot shifting at once. My selections for this week highlight where the pressure points are forming, and where the opportunities are emerging.
Electronics Manufacturing Needs Your Voice: Global Sentiment Survey Now Live
04/30/2026 | Global Electronics AssociationThe latest monthly Global Sentiment Survey from the Global Electronics Association is now open. At a time when demand uncertainty, policy shifts, energy costs, and supply chain recalibration are pulling the industry in multiple directions, the survey captures something macroeconomic data often misses: how manufacturers are actually experiencing conditions on the ground.
From Backbone to Breakthroughs: I-Connect007 Wraps PCB Materials Series with Focus on Innovation
05/04/2026 | I-Connect007I-Connect007 wraps up its six-part podcast series, PCB Materials: The Backbone and Future of Electronics, with Episode 6 and a discussion focusing on innovation. In Episode 6, Marcy LaRont speaks with Isola CTO Kirk Thompson about a critical turning point for the PCB industry as innovation accelerates. As data rates climb and demands from AI infrastructure, power density, flexible electronics, photonics, and chiplet integration intensify, traditional material assumptions are no longer sufficient.
Jiva Soluboard Getting the Attention It Deserves
04/30/2026 | Marcy LaRont, I-Connect007 MagazineJiva is a newer company that bridges the divide between PCB fabrication and product circularity or sustainability. Jiva Soluboard is the first fully recyclable laminate material ever created for PCB fabrication, and it's not going unnoticed. Stephen Driver, CEO of Jiva, gave us an update at APEX EXPO, including an exciting certification achievement in February.
Driving Innovation: Selecting the Right Laser Source
04/28/2026 | Simon Khesin -- Column: Driving InnovationWhen I first joined Schmoll Maschinen, I brought experience from almost every PCB process, except for laser. As I immersed myself in laser processing, I realized why it can seem so daunting to a newcomer. The complexity arises from three intersecting factors: A vast variety of laser sources: CO2, UV-nano, green-pico, UV-pico, IR-pico, and others; a diverse range of applications: Drilling, cutting, ablation, and more; and an extensive list of materials: These have vastly different absorption rates. Choosing the right machine or laser source is rarely trivial. Even for experienced engineers, answering "Which source is best?" requires examining the business's specific goals.