In a groundbreaking advance that merges cutting-edge computational biochemistry with innovative biological experimentation, researchers have unveiled a promising acridine-derived small molecule capable of modulating vascular endothelial growth factor (VEGF) activity. This novel compound demonstrates a profound influence on angiogenesis, as evidenced by its remarkable capacity to reduce vascularization in the chick chorioallantoic membrane (CAM) model, a well-established in vivo system for studying blood vessel formation. The implications of this discovery ripple through the realms of cancer therapy, ocular diseases, and other pathological states driven by aberrant blood vessel growth.

VEGF holds a pivotal role as a signal protein that stimulates the formation of blood vessels during both normal physiological processes and pathological conditions such as tumor growth and retinopathies. Therapeutic strategies targeting VEGF have seen extensive development, yet limitations including drug resistance and side effects demand new molecular candidates. The recent study leverages sophisticated in silico methodologies—molecular docking, dynamic simulations, and binding affinity calculations—to identify and characterize a small molecule from the acridine chemical family that interacts intimately with VEGF, subtly altering its bioactivity.

The choice to explore acridine derivatives stems from their chemical versatility and known biological activities. These planar, heterocyclic compounds have historically been employed in medicinal chemistry, often displaying anti-cancer and anti-microbial properties. In the context of VEGF inhibition, the planar structure offers a potential to engage in pi-stacking and hydrogen bonding with amino acid residues critical for VEGF receptor binding, thereby competitively or allosterically modulating function.

In silico predictions yielded compelling data: molecular docking revealed a high-affinity binding site where the acridine derivative securely associates with VEGF, primarily through hydrophobic interactions augmented by selective hydrogen bonds. Such computational insights not only illuminate the structural basis of interaction but also guide the rational design of derivatives with enhanced specificity and potency.

Transitioning from computational work to biological relevance, the study employed the CAM assay to empirically evaluate the vascular inhibitory effects of the acridine molecule. The CAM, a highly vascularized extra-embryonic membrane of the developing chick embryo, serves as an indispensable model for angiogenesis owing to its accessibility, rapid growth, and close resemblance to mammalian vascular development. Application of the small molecule resulted in a discernible reduction of new blood vessel formation, validating the computational hypothesis and underscoring the therapeutic potential of the compound.

This synchronized approach—combining in silico modeling with in vivo CAM assays—represents a paradigm shift in drug discovery, optimizing resource efficiency while enhancing predictive accuracy. Moreover, the decrease in CAM vascularization indicates a direct functional impact on endothelial cells, potentially via inhibition of VEGF signaling pathways that govern endothelial proliferation, migration, and survival.

Understanding how this acridine-derived molecule impacts VEGF at the molecular level could redefine therapeutic strategies against diseases characterized by pathological angiogenesis. Tumors exploit VEGF-mediated angiogenesis to secure their nutrient supply, enabling metastasis and growth. Inhibitors that can selectively disrupt VEGF without off-target toxicity could offer a renaissance in anticancer treatment, overcoming resistance mechanisms that curtail current therapies.

In addition to oncology, proliferative diabetic retinopathy and age-related macular degeneration represent clinical arenas where VEGF modulation has transformed patient outcomes. Yet, current anti-VEGF agents often require frequent administration and pose risks including intraocular inflammation. A novel small molecule capable of sustained or enhanced efficacy may alleviate these burdens, improving patient compliance and safety profiles.

Furthermore, the pharmacokinetic properties intrinsic to acridine derivatives might facilitate advantageous drug delivery, including tissue penetration and cellular uptake, attributes vital for clinical translation. The planar aromaticity and modifiable side chains open avenues for chemical optimization, aiming to refine solubility, stability, and target selectivity.

The integration of advanced molecular simulations with experimental verification also sets a precedent for future small-molecule discovery. The ability to virtually screen vast compound libraries for VEGF interaction prior to costly biological assays accelerates the pipeline from concept to candidate. Such methodologies promise to expand the arsenal of antiangiogenic agents, potentially uncovering molecules that act synergistically or via novel mechanisms.

Notably, the research reinforces the significance of interdisciplinary collaboration, merging computational chemistry, molecular biology, pharmacology, and developmental biology. This multifaceted strategy enhances confidence in findings and facilitates a comprehensive understanding of small molecule–protein dynamics and their biological ramifications.

The study’s revelations extend an invitation to the broader scientific community to explore acridine derivatives’ potential beyond VEGF inhibition. With structural adaptability and diverse bioactivity profiles, these compounds may address other molecular targets implicated in inflammatory, infectious, or neurodegenerative diseases, where angiogenesis or protein–ligand interactions are pivotal.

As this acridine-based compound progresses towards clinical evaluation, it will be critical to scrutinize toxicological profiles, metabolic stability, off-target effects, and effective dosing regimens. The translational journey necessitates balancing efficacy with patient safety, a formidable yet attainable goal given the compound’s targeted action and promising preliminary data.

In conclusion, the synergistic study that couples in silico molecular modeling with the CAM assay sets a milestone in angiogenesis research. The identification of a small molecule that associates specifically with VEGF and demonstrates tangible reductions in vascularization heralds a new chapter in targeted therapeutic development. By refining our molecular toolbox against angiogenic diseases, this work not only expands scientific horizons but also holds promise for improving countless lives affected by disorders of vascular dysregulation.

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Subject of Research: Interaction of an acridine-derived small molecule with VEGF to inhibit angiogenesis.

Article Title: Acridine-derived small molecule associates with VEGF and is linked to reduced CAM vascularization: a combined in silico and CAM study.

Article References:
Karmakar, S., Moulik, S., Ghosh, S. et al. Acridine-derived small molecule associates with VEGF and is linked to reduced CAM vascularization: a combined in silico and CAM study. BMC Pharmacol Toxicol (2026). https://doi.org/10.1186/s40360-026-01148-6

Image Credits: AI Generated

A groundbreaking discovery has reshaped our understanding of one of the most enigmatic groups in the animal kingdom: bryozoans. These tiny, colonial filter-feeders, omnipresent in today’s oceans, have long baffled paleontologists due to their conspicuous absence from the Cambrian fossil record. While the Cambrian explosion, occurring around 530 million years ago, heralded the rapid emergence of nearly all major animal phyla, bryozoans appeared to be absent until the Ordovician period, roughly 50 million years later. This puzzling gap, often dubbed the “elephant in the room” of Cambrian paleontology, may now be firmly closed thanks to the discovery of exquisitely preserved fossils from Southern China, dating back around 520 million years.

A multinational team of scientists from China, Sweden, Australia, and Germany recently unveiled a trove of fossils from the Xiannüdong Formation in southern Shaanxi Province. These fossils include detailed specimens of the previously known species Protomelission gatehousei and an entirely new genus and species, Dayingomelission hexaclitia. Both taxa thrived during the early Cambrian and provide compelling evidence that bryozoans were not only present but already exhibiting complex colony architectures at this early stage in animal evolution.

What sets these fossils apart is not solely their antiquity but the extraordinary quality of their preservation. The tiny colonies, each only a few millimeters in size, retain exquisite three-dimensional structures with internal soft tissues authentically mineralized in phosphate. This mineralization has allowed researchers to peer inside the original skeletal housing, revealing membranous sacs, minute muscle fibers, and distinctive skeletal features including diagnostic styles—unique structural spines characteristic of bryozoan anatomy. Such soft tissue detail is rarely captured in fossils this ancient, making these specimens an invaluable window into Cambrian marine ecosystems.

These findings decisively settle a long-standing debate over the affinities of these fossils. Some previous interpretations suggested Protomelission gatehousei could be a green alga or a collection of isolated, unrelated skeletal elements. However, the combination of hexagonal modular colony architecture and intricate internal anatomy makes the bryozoan affinity unequivocal. This marks an unprecedented confirmation that true bryozoans were indeed present during the Cambrian explosion, closing a perplexing gap in the fossil record.

Advanced imaging technologies played a crucial role in this breakthrough. Using state-of-the-art microscopic and tomographic techniques, researchers could visualize internal soft tissues and skeletal arrangements without damaging the specimens. This high-fidelity reconstruction allowed for a comprehensive phylogenetic analysis, clearly situating both Protomelission and Dayingomelission within Stenolaemata, one of the principal bryozoan classes still extant today. Such deep roots suggest that the bryozoan lineage originated even earlier than previously suspected—perhaps extending into the Ediacaran period, preceding the Cambrian radiation altogether.

These revelations carry profound implications for reconstructing early animal evolution. Bryozoans exhibit a highly modular colonial lifestyle in which genetically identical zooids cooperate within a shared skeleton—a key evolutionary innovation. The presence of fully developed modular colonies during the Cambrian implies that this mode of life was not a late development but a pivotal player in the Cambrian explosion itself. Consequently, the rise of complex multicellularity and functional integration within animal colonies must be reconsidered within this early evolutionary framework.

Additionally, the environmental context of these fossils offers insights into their preservation and ancient ecological niches. The bryozoans inhabited shallow, clear marine waters associated with reef settings—an environment contrasting with the deeper-water deposits typically yielding soft-tissue fossilization during the Cambrian. Such ecosystems may have fostered the radiation and diversification of early bryozoans, although their fossil record remained elusive until now due to specific taphonomic biases.

The significance of the discovery extends further: it suggests a more cosmopolitan distribution of early bryozoans in Cambrian seas. Combined with prior finds from ancient South Australian deposits, these Chinese fossils indicate that bryozoans were widespread and ecologically versatile much earlier than assumed. This cosmopolitanism hints at complex biogeographic patterns and diversification dynamics underpinning early marine ecosystems during one of Earth’s most transformative intervals.

Debunking alternative hypotheses about these Cambrian fossils not only clarifies bryozoan origins but also enhances our understanding of early marine biodiversity. A clearer timeline now places bryozoans as contemporaries of other foundational animal groups, reshaping models of early metazoan community structure. It emphasizes that the Cambrian explosion was as much about the emergence of novel ecological partnerships and colony-level complexity as it was about the appearance of individual taxa.

The ability to detect and interpret soft tissue mineralization in fossils surpasses traditional paleontological methods, underscoring technological advances that continue to revolutionize our window into deep time. These detailed anatomical insights would have been unthinkable decades ago, and they open fresh avenues for understanding evolutionary developmental biology and the genetic underpinnings of early animal form and function.

Moreover, the research highlights the synergy of international collaboration in paleontology. Combining expertise from institutions like Northwest University, the Swedish Museum of Natural History, and universities in Australia and Germany, alongside advanced imaging labs, coalesced into a breakthrough that will likely influence studies of other enigmatic Cambrian groups where fossil evidence remains scant or ambiguous.

In summation, these high-fidelity bryozoan fossils from the early Cambrian Xiannüdong Formation dramatically alter the evolutionary narrative of one of today’s most successful aquatic invertebrate phyla. By authenticating that bryozoans were indeed participants in the Cambrian explosion, this research closes a half-century-old mystery, revealing a much earlier and more complex history for these tiny, yet evolutionarily influential marine architects.

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Subject of Research: Animals
Article Title: High-fidelity modular skeletons authenticate a Cambrian origin for Bryozoa
News Publication Date: June 3, 2026
Web References: 10.1038/s41586-026-10590-9
Image Credits: Baopeng Song
Keywords: Cambrian explosion, bryozoans, Protomelission gatehousei, Dayingomelission hexaclitia, fossil record, modular colonies, early animal evolution, soft tissue preservation, Stenolaemata, phosphate fossilization, Xiannüdong Formation, paleontology

In a remarkable archaeological breakthrough near Regensburg in Bavaria, Germany, a nearly 2.5-meter-long spirally twisted tusk belonging to a woolly mammoth (Mammuthus primigenius) was unearthed during routine construction work in Taimering. This discovery, made six years ago by the Bavarian State Office for the Preservation of Historical Monuments (BLfD), reverberates profoundly through the scientific community, offering an unparalleled window into the Ice Age fauna of Central Europe. Alongside the tusk, researchers uncovered over seventy additional bones and bone fragments predominantly from the mammoth’s ribcage, as well as hand and foot bones, though the long bones remain conspicuously absent. Experts attribute the exceptional preservation of these remains to millennia of conservation within the wet sedimentary environment, which staved off the deleterious effects typically inflicted by exposure and predation.

Subsequent paleontological analyses meticulously confirmed that all the bones and the tusk belong to a single, remarkably large but juvenile individual. The mammoth is estimated to have stood approximately three meters tall at the shoulder—indicative of the species’ impressive stature even before reaching full maturity. The spatial arrangement and pristine condition of the bones strongly imply that the animal perished in close proximity to the excavation site. Detailed surface examinations revealed the absence of evidence for transport by water or predation-induced disarticulation, suggesting rapid burial in the sediments of an ancient pond or a slow-moving tributary of the Danube River during the Last Glacial Maximum. Radiocarbon dating places this event between 27,000 and 25,000 years ago, embedding the specimen firmly within a critical temporal context.

One of the most striking revelations from the site involved the identification of anthropogenic modifications on the bones. Researchers discerned clear cut marks—most notably on the ribs—attesting to human butchering activities. Intriguingly, one of the broad rib bones appears to have served as a makeshift cutting board, further underscoring the direct interaction between Palaeolithic humans and this megafaunal giant. However, it remains unresolved whether humans hunted the mammoth or scavenged its carcass after natural death. The osteoarchaeological analyses led by Kerstin Pasda from the Friedrich-Alexander-University Erlangen-Nürnberg provide compelling evidence of deliberate exploitation but stop short of clarifying the exact nature of the encounter.

Pollen analysis by Dr. Philipp Stojakowits from the University of Augsburg provided vital environmental context, revealing a tundra-like steppe populated by herbaceous plants and scattered dwarf shrubs. This biome, commonly known as the Mammoth Steppe, was a complex and nutrient-rich ecosystem that stretched expansively across Eurasia during the peak of the last glaciation from 30,000 to 20,000 years ago. It represented a vast treeless habitat nestled between the retreating Scandinavian ice sheet and the southern Alpine glaciers, capable of sustaining diverse megafauna including woolly mammoths. The palaeoecological insights gleaned from these studies place the Taimering mammoth within an ecosystem marked by climatic extremes yet surprisingly rich biodiversity.

This discovery is of exceptional significance not only because mammoth remains are exceedingly rare in this part of Europe but also due to the scarce evidence of human presence in the region during this notoriously harsh glacial period. PD Dr. Gertrud Rößner, a leading paleontologist at the Bavarian State Collections of Natural History, highlighted the rarity of such finds in Central Europe, contrasting with more common discoveries in eastern Eurasia. Additionally, archaeologists Andreas Maier of the University of Cologne and Thorsten Uthmeier of the Friedrich-Alexander-University Erlangen-Nürnberg emphasized that prevailing climatic conditions likely forced Palaeolithic hunter-gatherers to seek refuge in more hospitable southern and eastern zones, rendering direct evidence of their activities exceedingly rare in Bavaria.

The collaborative scientific endeavor involved 14 specialists from a panoply of institutions including the Bavarian State Collections of Natural History, Friedrich-Alexander University Erlangen-Nürnberg, the Bavarian State Office for the Preservation of Historical Monuments, the Reiss-Engelhorn Museums, the Curt Engelhorn Center for Archaeometry in Mannheim, and several major universities across Germany. This interdisciplinary approach ensured comprehensive analyses employing advanced archaeological, palaeontological, and geological techniques, culminating in a robust reconstruction of the mammoth’s life and death against the backdrop of Ice Age Europe.

Such integrated research has immense implications. Beyond expanding the paleobiogeographical distribution of woolly mammoths, the site furnishes rare evidence of human predation or scavenging behavior in an environmental context generally considered hostile to sustained human occupation during the Last Glacial Maximum. The cut marks on the bones, coupled with contextual geological data, provide a rare snapshot into hominin subsistence strategies and adaptability under extreme climatic stress, critical for understanding human evolution and migration patterns during this epoch.

Moreover, the preservation of the mammoth’s tusk alongside the skeletal remains offers valuable material for ongoing studies related to the species’ growth patterns, physiology, and ecological niche. The tusk’s spiral curvature—a characteristic feature in Mammuthus primigenius—provides insights into the age and health status of the individual, while microscopic analyses of growth increments may yield data on environmental fluctuations and dietary intake. The care taken in meticulously extracting and preparing these finds at the Bavarian State Collections of Natural History underscores the scientific potential locked within these ancient relics.

Attention to the depositional environment has also yielded critical stratigraphic information. The wet-soil conditions responsible for the near-perfect conservation of the bones also hint at palaeo-hydrological dynamics of the region during the Ice Age. These insights are invaluable for reconstructing the geomorphology of prehistoric landscapes and understanding how megafaunal species interacted with their habitats, maneuvered across glacial terrains, and responded to rapidly changing environmental parameters.

In summary, the Taimering mammoth discovery challenges and enriches prevailing narratives about Ice Age Europeans and their megafauna. It bridges gaps between palaeontology, archaeology, and palaeoecology, providing a multidimensional view of an ancient world teetering on the edge of monumental climatic upheaval. This research not only celebrates a spectacular scientific find but also sets a new standard for interdisciplinary collaboration in Quaternary science, offering promising avenues for further revelations about the complex interplay between humans and their environment tens of millennia ago.

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Subject of Research: Animals

Article Title: A cold case from the last Glacial Maximum: A partial mammoth skeleton from southern Germany (Danube Valley, Germany) – Part 1: Traces of human activity and archaeological context

News Publication Date: 3-Jun-2026

Web References:
http://dx.doi.org/10.1016/j.jasrep.2026.105839

Image Credits: Credit: BLfD

Keywords: Woolly mammoth, Mammuthus primigenius, Ice Age, Last Glacial Maximum, archaeology, palaeontology, human activity, butchering marks, Mammoth Steppe, palaeoecology, radiocarbon dating, Bavaria, Central Europe.

While searching for new Higgs bosons the CMS experiment at the Large Hadron Collider (LHC) may have just found a surprise. They have observed an excess of events that look to be a new particle, and are reporting high statistical evidence for their claim. The only question is what exactly is this new particle?

The search was initially designed to look for new, heavier, versions of the Higgs boson decaying to a top quark and an anti-top quark. Its well known that the Higgs boson of the Standard Model, discovered jointly by ATLAS and CMS in 2012, underlies the mechanism which gives all fundamental particles their masses. The Higgs boson itself interacts with particles in proportion to their mass, preferring heavier particles over lighter ones. It therefore interacts the most strongly with the heaviest known fundamental particle, the top quark, which has a mass of ~173 GeV. The Higgs boson itself only has a bass of 125 GeV, meaning conservation of energy dictates it can’t decay into a top quark-antiquark pair.

However many theories of physics beyond the the Standard Model predict additional Higgs bosons, heavier cousins of the current one. If these new heavy Higgs bosons had a mass larger than 350 GeV, they would likely decay to a top quark-antiquark pair quite often. CMS therefore was analyzed its data searching for this signature, hoping to find signs of a new Higgs boson. To do so, they had scrutinize very carefully the known production of top quark-antiquark pairs, which are produced copiously at the LHC from other processes. If a new particle was being produced and decaying to top quarks, the mass of the new particle would give the top quarks a characteristic energy. One key sign of a new particle would therefore be an excess of top quark-antiquark events at a particular energy, corresponding to the mass of the new particle. 

When CMS scrutinized their data looking for such an excess they found one. But curiously right ~350 GeV, the minimum energy required to produce the top quark-antiquark pair. It would be quite the coincidence for a new particle to show up right at this minimum threshold, which made CMS consider alternative possibilities.

 

 One unorthodox explanation that seems to fit the bill is ‘toponium’, a short lived bound state of the top quark-antiquark pair is being formed. Toponium would be the heaviest version of ‘quarkonia’ we have seen, bound states of quark antiquark pairs that form bound states similar to atoms. We have observed and measured quarkonia states of the other quarks for decades, however it was long thought that the top quark, whose large mass causes it to decay in just 10^(-25) seconds, would decay too quickly to create observable bound state effects at a hadron collider. Toponium production would happen most often if the top quarks were produced just at the energy threshold, such that they don’t any extra energy. These low energy top quarks would spend more time close to each other than normal, rather than immediately flying away, so they could have time to briefly form a toponium state before decaying. However, once small hints of intriguing excesses started appearing in LHC analyses, updated calculations in the last few years suggested that perhaps such an effect could be observable.

These calculations are approximate, and more work is still being done to refine them. But the preliminary predictions they give for the properties of toponium seem to match well with what CMS is seeing, both in terms of the rate of toponium production and the quantum properties of the toponium state (spin and parity).

Still CMS is being cautious before claiming a discovery of toponium. They claim observation of an ‘excess at the top quark pair production threshold’ which is consistent with toponium. However given the limited present data and incomplete theoretical models of toponium, they cannot rule out that the excess they are seeing is coming from a new Higgs-like particle.

Further work will be needed to develop improved theoretical models of toponium, and detailed studies from CMS assessing the properties of their observed excess. The excess will also need confirmation from CMS’s rival LHC experiment, ATLAS, to ensure it has not merely made a mistake in its analysis.

However, the smart money would say this very likely looks like toponium. Which, while not signaling the long sought overthrow of the standard model, would be an unexpected and cool surprise from the LHC. Understanding the properties of this previously-thought-impossible quasiparticle will spawn much fruitful research in the years to come. Physicists love a surprise!

Paper:

“Observation of a pseudoscalar excess at the top quark pair production threshold” https://arxiv.org/abs/2503.22382

Additional CMS Paper considering Heavy-Higgs interpretation “Search for heavy pseudoscalar and scalar bosons decaying to top quark pairs in proton-proton collisions”

Read more

CERN Courier “CMS observes top–antitop excess“

Symmetry Magazine “Don’t call it toponium“

Discloure: The author is a member of the CMS collaboration but did not directly work on this analysis

Erratum 4/15/2025 : The article was updated to clarify that in the theory literature prior to the LHC toponium was thought possible to form, just that it was thought to be too small an effect to be observable. The article previously incorrectly stated it had been previously thought impossible to form

In a groundbreaking revelation that challenges long-standing assumptions in the field of frost formation, researchers at the University of Illinois Urbana-Champaign have unveiled a previously unknown mechanism by which frost propagates on surfaces. Led by Professor Nenad Miljkovic from The Grainger College of Engineering, the team’s study introduces the discovery of “suspended ice bridges,” distinct spatial modes of ice bridge formation that occur in stark contrast to the conventional understanding whereby ice bridges grow strictly along the substrate. Their findings, published in the prestigious journal Nature Physics, not only deepen scientific comprehension of frost dynamics but also herald innovative strategies for designing anti-frosting surfaces critical to a wide range of engineering applications.

The formation and propagation of frost is a critical consideration in the design and operation of many technological systems, including but not limited to air-source heat pumps, refrigeration units, and aerospace components. At the microscopic scale, frost spreads primarily through the creation of ice bridges—connective formations that link neighboring supercooled liquid droplets, effectively enabling freezing fronts to advance rapidly across surfaces. For decades, it has been widely accepted, largely based on conventional top-view imaging methods, that these ice bridges advance in two dimensions, traveling along the solid substrate. The Illinois team’s novel research radically revises this view by revealing a three-dimensional aspect to ice bridge growth.

Employing advanced high-resolution optical microscopy complemented by a sophisticated technique known as focal plane shift imaging (FPSI), the researchers were able to visualize frost formation processes in unprecedented detail. This approach enabled them to identify two distinct modes of spatial ice bridge growth that depend heavily on surface wettability. On hydrophilic, or water-attracting, surfaces, ice bridges conform to existing models and propagate along the substrate, consistent with established understanding. Conversely, on superhydrophobic surfaces, which repel water, ice bridges exhibit a unique suspended growth mode, extending above the surface and bridging droplets through the air rather than along the solid interface beneath.

This suspended, or “out-of-plane,” mode of ice bridge formation represents a fundamental departure from previously accepted frost propagation models. Its discovery has been largely overlooked until now due to methodological constraints in prior experimental observations. The significance lies not only in its novelty but also in the profound implications it holds for frost management technologies. According to first author Dr. Siyan Yang, a postdoctoral researcher under Professor Miljkovic, the surface’s wettability is the pivotal parameter that controls the transition between these two ice bridge growth modes.

Through systematic experimentation varying the apparent contact angles of water droplets on different surfaces, the research team identified a critical threshold near 105 degrees. Above this value, typical of superhydrophobic surfaces, suspended ice bridges become the dominant frost propagation route. This insight adds a crucial layer to our understanding: wettability influences not just droplet behavior and spacing but fundamentally governs the three-dimensional architecture of ice bridge growth, redirecting freezing pathways and thereby affecting frost dynamics in ways not previously appreciated.

The researchers further elucidated the mechanisms governing the spatial mode of ice bridges by examining the droplet geometries and corresponding vapor diffusion pathways intrinsic to each surface type. On superhydrophobic surfaces, the geometric configuration of droplets alters the shortest path through which vapor diffuses, shifting it away from the substrate and favoring airborne bridge formation. This anatomical shift arises because droplets adopt a more spherical shape, which minimizes the area of contact with the underlying surface and affects vapor transport dynamics, creating conditions favorable for suspended ice bridges.

One of the most striking findings was the markedly slower growth rate of suspended ice bridges compared to their substrate-attached counterparts. This pronounced deceleration stems from the diminished thermal coupling between the suspended ice bridge and the cold substrate below, which effectively reduces the vapor pressure gradients responsible for driving ice accretion. Consequently, frost propagation is substantially impeded on superhydrophobic surfaces displaying suspended ice bridge formation, representing a potent natural defense against frost accumulation.

Experimentally, the Illinois team demonstrated that frost propagation speed can be diminished by more than 80 percent on surfaces promoting the suspended ice bridge mode. This breakthrough has immediate practical relevance, as it directly translates to enhanced operational efficiencies and prolonged performance lifetimes in frost-sensitive systems. To validate this, the researchers extended their experimental framework to encompass commercial finned-tube heat exchangers. These components are ubiquitous in heating, ventilation, air conditioning (HVAC), and refrigeration systems and often suffer from efficiency losses due to frost buildup.

The results obtained from tests on these heat exchangers corroborated the laboratory findings, showcasing that surfaces engineered to support suspended ice bridges can dramatically delay the onset of frost, slow its propagation, and consequently sustain optimal heat transfer performance over extended periods. This represents a crucial advancement in linking microscopic frost structure behavior to macroscopic system-level outcomes. By providing this mechanistic understanding, the research opens the door to the rational design of surfaces that strategically manipulate ice bridge formation to curb frost accumulation and improve energy efficiency.

This discovery also challenges the conventional two-dimensional framework of frost propagation, calling for a re-examination of theoretical models from a three-dimensional perspective. Recognizing that ice bridge growth can extend above the surface plane compels scientists and engineers to reconsider frost formation dynamics and interfacial heat transfer processes in materials and devices exposed to frost conditions. The new paradigm not only reshapes fundamental phase change science but could ripple across disciplines involved in thermal management and surface science.

Professor Miljkovic underscored the transformative potential of these findings by emphasizing how the deeper understanding of ice bridge formation will catalyze innovative surface engineering efforts. These efforts aim to tailor interfacial properties to regulate frost spreading deliberately, fostering more energy-efficient thermal management and phase change systems. The possibility of controlling frost at the microscale through surface wettability and geometry adjustments marks a pivotal step toward technologically advanced, frost-resilient surfaces.

Dr. Siyan Yang’s role as principal experimenter and co-author underscores the multidisciplinary expertise fueling the breakthrough. Her extensive research in frost nucleation, propagation mechanisms, and anti-icing surface design has led to numerous influential publications in high-impact journals and multiple invention patents. The convergence of physics, materials science, and engineering in this study exemplifies the burgeoning field of interface-driven energy transport phenomena.

Together with a diverse team of collaborators, Miljkovic and Yang’s pioneering work redefines the fundamental science of frost formation, presenting suspended ice bridges as a novel, three-dimensional mechanism with profound implications for future research and practical applications. This advancement represents a seminal leap, promising not only enhanced understanding but also transformative technologies for energy and thermal management systems facing the perennial challenge of frost.

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Subject of Research: Frost propagation mechanisms and surface-driven ice bridge formation during sessile droplet freezing.

Article Title: Growth and control of suspended ice bridges during sessile droplet freezing

News Publication Date: 28-May-2026

Web References:
https://www.nature.com/articles/s41567-026-03296-2
http://dx.doi.org/10.1038/s41567-026-03296-2

References:
Yang, S., Chu, F., Ganesan, V., Faghihi, P., Ghaddar, D., Zhang, W., Liu, J., Yang, J.B., Huang, A., Boyina, K., Chettiar, K., Dewanjee, S., Aflatounian, S., Khan, R., Braun, P.V., Feng, J., Poulikakos, D., Miljkovic, N. (2026). Growth and control of suspended ice bridges during sessile droplet freezing. Nature Physics.

Image Credits: The Grainger College of Engineering at the University of Illinois Urbana-Champaign

Keywords

Frost propagation, ice bridges, suspended ice bridges, superhydrophobic surfaces, hydrophilic surfaces, sessile droplet freezing, surface wettability, frost mitigation, vapor diffusion pathways, thermal management, phase change phenomena, anti-frost surfaces