Hydrogel Traps Fleeting Plasma Radicals to Trigger Cancer Cell Death

Cold atmospheric plasma has long intrigued cancer researchers because of a remarkable selectivity: in laboratory studies and early clinical settings, the ionized gas cocktail it produces can kill a broad range of cancer cells while leaving their non-malignant neighbors largely unharmed. Yet the technology has remained confined mostly to a narrow niche, adjuvant treatment during surgery, because its most potent ingredients are also its most ephemeral. The short-lived radicals that drive much of plasma’s anticancer activity vanish within microseconds, making it nearly impossible to bottle them, ship them, or apply them outside the immediate vicinity of a plasma device. A new study published in Advanced Composites and Hybrid Materials reports a way to do precisely that, trapping these fleeting reactive species in a stable hydrogel and preserving them for weeks.

The research team, led by Xiaofeng Dai, Yixuan Yang, Xibo Xue, and Yi Lv of the First Affiliated Hospital of Xi’an Jiaotong University, developed a material they call FAE@CHG. The system combines two engineered components: functional nanoparticles that capture short-lived radicals generated by cold atmospheric plasma, and a tyramine-conjugated hyaluronic acid hydrogel that holds the loaded nanoparticles in place and releases their cargo gradually over time. According to the authors, this hybrid platform preserved highly reactive oxygen and nitrogen species for up to three weeks, an extraordinary extension of lifetimes that naturally range on the order of microseconds.

To understand why this matters, it helps to consider what cold atmospheric plasma actually is. Unlike the hot plasmas found in stars or fusion reactors, cold atmospheric plasma operates near room temperature at atmospheric pressure, typically generated by applying high voltage to a gas such as helium or air. The result is a complex mixture of electrons, ions, ultraviolet photons, and chemically active molecules, including reactive oxygen species such as hydroxyl radicals and hydrogen peroxide, and reactive nitrogen species such as nitric oxide. The short-lived radicals among these are widely considered central to plasma’s potent anticancer effects, but they decay almost instantly upon contact with surfaces or liquids, which has severely limited how the technology can be delivered.

One workaround that researchers have explored is plasma-activated medium, in which a liquid is exposed to plasma and then applied to cells or tissue. The problem, as the study’s authors note, is that such liquids end up dominated by longer-lived species like hydrogen peroxide and nitrite, while the short-lived radicals that make direct plasma treatment so effective are lost almost entirely. Plasma-activated medium therefore captures only a fraction of plasma’s therapeutic chemistry. The new hydrogel strategy was designed specifically to close that gap, giving clinicians a way to store and transport the most reactive components of plasma rather than settling for their diluted, longer-lived remnants.

The capturing element of the system, designated FAE, consists of nanoparticles with a magnetic iron oxide core, a gold shell, and a functional surface layer, produced by pre-treating the particles with cold atmospheric plasma. These nanoparticles act as radical sponges, binding the short-lived reactive species generated during plasma exposure. The second element, HAT, is a hydrogel formed from hyaluronic acid conjugated with tyramine, a modification that allows the gel network to be stabilized and tuned for sustained release. Together, the nanoparticle-hydrogel composite holds the captured radicals in a form that remains chemically active long after the plasma source has been switched off.

Three weeks of preservation is not merely a storage convenience. It transforms the logistics of plasma medicine. A treatment that once required a plasma generator at the bedside could, in principle, be prepared in advance, stored, and applied topically like a conventional pharmaceutical gel. The authors emphasize that this is the first successful integration of plasma-derived short-lived reactive species into a gel-based platform, a milestone that could expand plasma therapy’s administration routes well beyond the operating theater and the direct-contact applicator.

The team tested their material against cutaneous squamous cell carcinoma, a common skin cancer, chosen both for its clinical relevance and for its accessibility to topical treatment. In cell studies, FAE@CHG produced a potent and selective anticancer response, attacking tumor cells while sparing non-malignant counterparts. What distinguishes the mechanism is its breadth: rather than triggering a single death pathway, the trapped radicals activated multiple regulated cell death programs simultaneously. The authors report that this coordinated assault was primarily orchestrated by disulfidptosis, a recently identified form of regulated cell death driven by the accumulation of disulfide molecules that disrupt the actin cytoskeleton and cause cells to collapse and die.

Disulfidptosis is an unusually attractive mechanism for cancer therapy because it depends on cellular metabolic vulnerabilities that many tumors cannot easily evade. Unlike apoptosis, the most familiar cell death pathway, disulfidptosis can be induced under conditions of high glucose and impaired disulfide metabolism, and cancer cells with certain metabolic profiles are particularly susceptible. By making disulfidptosis the primary orchestrator of cell death while simultaneously engaging additional pathways, the hydrogel appears to present tumor cells with a multi-front challenge that is harder to resist than any single mechanism. Resistance to cancer therapies often emerges when cells adapt to one death pathway; concurrent activation of several may reduce the escape routes available.

Animal models provided the crucial confirmation that the laboratory results translated into living systems. Tumors treated with FAE@CHG showed enhanced efficacy compared with control treatments, and the material caused no apparent systemic toxicity whether applied topically or as part of an integrated treatment regimen. That safety profile is essential for a platform built on reactive chemistry, since the same radical species that kill cancer cells can damage healthy tissue if released indiscriminately. The hydrogel’s ability to contain and gradually release these species appears to concentrate their effects where they are needed while protecting surrounding tissue.

The work was funded by the National Natural Science Foundation of China, and the authors declare no competing interests. Its implications extend beyond skin cancer. Because the platform is modular, a hydrogel loaded with plasma-activated nanoparticles could potentially be adapted to other tumor types, combined with existing therapies, or engineered for different release profiles. It also addresses a persistent criticism of plasma medicine, namely that its clinical translation has been hampered by the difficulty of delivering its active chemistry in a controlled, reproducible way. By converting a transient physical phenomenon into a storable, stable material, the researchers have effectively turned cold atmospheric plasma from a device-dependent procedure into something closer to a drug. If subsequent studies replicate these findings and establish clinical safety, the microsecond radicals that once evaporated into thin air could become a lasting weapon in oncology’s arsenal.

Subject of Research: A nanoparticle-hydrogel platform that preserves short-lived cold atmospheric plasma radicals to induce disulfidptosis in cutaneous squamous cell carcinoma

Article Title: A strategy trapping transient radicals from cold atmospheric plasma triggers disulfidptosis of cancer cells

Article References: Dai, X., Yang, Y., Xue, X., & Lv, Y. (2026). A strategy trapping transient radicals from cold atmospheric plasma triggers disulfidptosis of cancer cells. Advanced Composites and Hybrid Materials. https://doi.org/10.1007/s42114-026-02051-8

Image Credits: AI Generated

DOI: 10.1007/s42114-026-02051-8

Keywords: cold atmospheric plasma, disulfidptosis, hydrogel, reactive oxygen species, nanoparticles, cutaneous squamous cell carcinoma, plasma medicine, regulated cell death, cancer therapy, radical preservation, hyaluronic acid, drug delivery