Low-Temperature Plasma Techniques in Biomedical Applications and Therapeutics: An Overview

Pediatric Burn Treatment with Non-Thermal Atmospheric Plasma and Epifast®: Clinical Results

The effective treatment of severe burns in pediatric patients is essential for minimizing complications and promoting optimal recovery. This study investigates the use of non-thermal atmospheric pressure plasma (NTAPP) as an adjuvant therapy in combination with Epifast® for the experimental group, compared to standard care involving early excisions and Epifast® for the control group. A randomized controlled trial was conducted with 40 pediatric patients suffering from superficial partial-thickness and deep dermal burns. The experimental group that received NTAPP daily demonstrated a significant reduction in the need for skin grafts, requiring only 10% compared to 40% in the control group (p = 0.02). Although there were no statistically significant differences in the length of hospital stay, the experimental group showed a trend toward shorter stays (9.85 days vs. 11.65 days; p = 0.38) and lower analgesic consumption (13.01 doses vs. 21.15 doses; p = 0.09). Additionally, the infection rate in the NTAPP-treated group was significantly lower at 25%, compared to 37.95% in the control group (p < 0.05). These findings suggest that NTAPP enhances wound healing while reducing surgical morbidity and the risk of infections. In conclusion, this study highlights the transformative potential of NTAPP as an innovative strategy in pediatric burn management. It combines clinical efficacy with a less invasive approach, representing a significant advance in regenerative medicine and opening new avenues for research into advanced therapies.

Innovative Therapeutic Approach Targeting Colon Cancer Stem Cells: Transitional Cold Atmospheric Plasma

Transitional cold atmospheric plasma (TCAP) represents a novel technique for generating plasma remotely from a primary source. It consists of a partially nonthermal ionized gas mixture containing charged and neutral particles, photons, and free radicals. In recent years, TCAP has attracted considerable attention in biomedical applications. In order to evaluate colon cancer stem cells' (CCSCs) proliferation, apoptotic induction, inflammatory response, and survival, TCAP was utilized both directly and indirectly in this study. Using argon and helium gases, TCAP was continuously delivered in two stages during the experiment. For direct state, TCAP was irradiated onto CCSCs for 3 and 5 min. In the indirect technique, Matrigel was treated with TCAP for 5 min before the introduction of cells. In vitro assays demonstrated that TCAP exposure significantly reduced the viability of CCSCs; helium gas and direct application had greater impacts than argon. Numerous investigations confirmed the induction of apoptosis, showing that the treated groups had more apoptotic cells and altered cellular structures than controls (****p < 0.0001). A substantial increase in the Bax/Bcl-2 ratio was found by analyzing the expression of the Bax and Bcl-2 genes, indicating increased susceptibility to apoptosis (*p = 0.0177 and ***p = 0.0004). The higher efficacy of the direct helium mode was further highlighted by inflammatory marker analysis, which showed a significant reduction in interleukin-6 and interleukin-8 expression in cells directly treated with TCAP-helium compared to TCAP-argon (**p = 0.0015 and ***p = 0.0007). Lastly, the proliferation test, which relies on K i-67 expression, demonstrated a noteworthy decline in all TCAP-treated groups, with the direct helium group exhibiting the most robust impact (**p = 0.0014). Overall, the findings highlight the potential of TCAP, particularly with helium, as a promising approach for selectively targeting CCSCs and providing insights into its therapeutic mechanisms for cancer treatment. TCAP, therefore, emerges as a unique therapeutic strategy with potential applications in cancer stem cell-targeted therapies.

Insights into biofilm-mediated mechanisms driving last-resort antibiotic resistance in clinical ESKAPE pathogens

The rise of antibiotic-resistant bacteria poses a grave threat to global health, with the ESKAPE pathogens, which comprise Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp. being among the most notorious. The World Health Organization has reserved a group of last-resort antibiotics for treating multidrug-resistant bacterial infections, including those caused by ESKAPE pathogens. This situation calls for a comprehensive understanding of the resistance mechanisms as it threatens public health and hinder progress toward the Sustainable Development Goal (SDG) 3: Good Health and Well-being. The present article reviews resistance mechanisms, focusing on emerging resistance mutations in multidrug-resistant ESKAPE pathogens, particularly against last-resort antibiotics, and describes the role of biofilm formation in multidrug-resistant ESKAPE pathogens. It discusses the latest therapeutic advances, including the use of antimicrobial peptides and CRISPR-Cas systems, and the modulation of quorum sensing and iron homeostasis, which offer promising strategies for countering resistance. The integration of CRISPR-based tools and biofilm-targeted approaches provides a potential framework for managing ESKAPE infections. By highlighting the spread of current resistance mutations and biofilm-targeted approaches, the review aims to contribute significantly to advancing our understanding and strategies in combatting this pressing global health challenge.

Applications of low-temperature plasma technology in microalgae cultivation and mutant breeding: A comprehensive review

Low-temperature plasma (LTP) has gained significant attention recently due to its unique properties and potentially wide applications in agriculture, medicine, and food industry. Microalgae have become important to human life since they provide raw materials and bioactive products to industries. This review especially examines how LTP technology can be utilized to enhance microalgae growth and production of various metabolites and bioactive compounds such as astaxanthin, biofuel, lipid, proteins, and polysaccharides through mutagenesis and/or stimulation. Also, this review suggests that LTP may be combined with multi-omics tools such as proteomics, transcriptome, metabolomics and advanced methods such as single-cell analysis techniques to provide a promising strategy for acquiring desirable strains in algal mutant breeding and for enhancing the production of bioactive compounds in the microalgae. By shedding light on the benefits and applications of LTP, we hope to inspire new solutions to the challenges of commercial-scale microalgae development.

Low-temperature cold plasma promotes wound healing by inhibiting skin inflammation and improving skin microbiome

Wound healing includes four consecutive and overlapping stages of hemostasis, inflammation, proliferation, and remodeling. Factors such as aging, infection, and chronic diseases can lead to chronic wounds and delayed healing. Low-temperature cold plasma (LTCP) is an emerging physical therapy for wound healing, characterized by its safety, environmental friendliness, and ease of operation. This study utilized a self-developed LTCP device to investigate its biological effects and mechanisms on wound healing in adult and elderly mice. Histopathological studies found that LTCP significantly accelerated the healing rate of skin wounds in mice, with particularly pronounced effects in elderly mice. LTCP can markedly inhibit the expression of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) and senescence-associated secretory phenotype factors (MMP-3, MMP-9), while significantly increasing the expression of tissue repair-related factors, such as VEGF, bFGF, TGF-β, COL-I, and α-SMA. It also regulated the expression of genes related to cell proliferation and migration (Aqp5, Spint1), inflammation response (Nlrp3, Icam1), and angiogenesis (Ptx3, Thbs1), promoting cell proliferation and inhibit apoptosis. Furthermore, LTCP treatment reduced the relative abundance of harmful bacteria such as Delftia, Stenotrophomonas, Enterococcus, and Enterobacter in skin wounds, while increasing the relative abundance of beneficial bacteria such as Muribaculaceae, Acinetobacter, Lachnospiraceae NK4A136_group, and un_f__Lachnospiraceae, thereby improving the microbial community structure of skin wounds. These research findings are of significant implications for understanding the mechanism of skin wound healing, as well as for the treatment and clinical applications of skin wounds, especially aging skin.

Cold Plasma Treatment Facilitated the Conversion of Lignin-Derived Aldehyde for Pseudomonas putida

Syringaldehyde derived from lignin is one of the essential intermediates for the production of basic chemicals. However, it was poorly understood for the direct microbial conversion of syringaldehyde. Here, this study tried to use cold plasma technique to enhance syringaldehyde conversion for the bacterium Pseudomonas putida. It illustrated that cell growth and syringaldehyde conversion were separately increased by 1.49 times at 3 h and 1.60 times at 6 h for 35 s, 1.16 and 3.44 times for 140 W, and 1.63 and 4.02 times for 105 Pa for P. putida through single factor assays of cold plasma treatment. To be sure, cell growth and syringaldehyde conversion were enhanced by 1.14 and 5.54 times at 3 h under the optimum parameters (35 s, 140 W, and 105 Pa) for P. putida. Furthermore, genome re-sequencing further discovered single-nucleotide polymorphisms of P. putida, such as PP_2589 (A428V), PP_5651 (V82F), and PP_0545 (W335R), and thus indicated that the potential genetic changes derived from cold plasma treatment would be responsible for the acceleration of syringaldehyde conversion. This work would provide a robust strain catalyst and the potential candidate mutation sites for genetic manipulation for microbial bioconversion of the value-added and lignin-based biochemicals.

On the Synergistic Effects of Cold Atmospheric Pressure Plasma Irradiation and Electroporation on Cytotoxicity of HeLa Cells

Cold atmospheric plasma (CAP) treatment induces cancer cell death through the generation of reactive oxygen and nitrogen species (RONS). However, the efficacy of RONS delivery into cells remains limited by membrane permeability. Here, we investigated whether combining CAP with pulsed electric fields (PEFs) could enhance cancer cell death through increased intracellular RONS uptake. HeLa cells were treated with argon atmospheric pressure plasma jet (Ar-APPJ), PEF, or their combination. The combined treatment showed significantly enhanced cell death compared to single treatments. While PEF treatment alone induced membrane permeabilization, the combination with Ar-APPJ resulted in more pronounced and sustained membrane disruption, as evidenced by increased calcein leakage. This enhanced effect was attributed to Ar-APPJ-induced lipid peroxidation interfering with membrane resealing after PEF-induced electroporation. We also demonstrated that PEF-induced membrane electroporation facilitates the intracellular uptake of CAP-generated RONS. These findings provide mechanistic insights into the synergistic effects of combined CAP and PEF treatments, suggesting enhanced cell death via multiple pathways.

Plasma Optimization as a Novel Tool to Explore Plant-Microbe Interactions in Climate Smart Agriculture

Plasma treatment has emerged as a promising tool for manipulating plant microbiomes and metabolites. This review explores the diverse applications and effects of plasma on these biological systems. It is hypothesized that plasma treatment will not induce substantial changes in the composition of plant microbiomes or the concentration of plant metabolites. We delve into the mechanisms by which plasma can regulate microbial communities, enhance antimicrobial activity, and recruit beneficial microbes to mitigate stress. Furthermore, we discuss the optimization of plasma parameters for effective microbiome interaction and the role of plasmids in plant-microbe interactions. By characterizing plasmidome responses to plasma exposure and investigating transcriptional and metabolomic shifts, we provide insights into the potential of plasma as a tool for engineering beneficial plant-microbe interactions. The review presented herein demonstrates that plasma treatment induces substantial changes in both microbial community composition and metabolite levels, thereby refuting our initial hypothesis. Finally, we integrate plasmidome, transcriptome, and metabolome data to develop a comprehensive understanding of plasma's effects on plant biology and explore future perspectives for agricultural applications.

Enhanced surface hydrophilicity improves osseointegration of titanium implants via integrin-mediated osteoimmunomodulation

Titanium (Ti) implants have become widespread especially in dentistry and orthopedics, where macrophage-driven osteoimmunomodulation is crucial to their success. Hydrophilic modification of Ti represents a promising strategy to enhance its immune and osteogenic responses. Herein, the osteoimmunomodulatory performance and integrin-mediated mechanism of novel non-thermal atmospheric plasma (NTAP) treatment to induce a hydrophilic Ti were investigated for the first time. Compared to a hydrophobic surface, NTAP-modified Ti possessed a 3-fold increase of pro-healing M2 macrophage makers, and the doubled osteogenic differentiation of mesenchymal stem cells was demonstrated in this immune microenvironment, thus improving early osseointegration. Mechanistically, the ameliorative osteoimmunomodulatory properties of NTAP were attributed to its positive and negative modulation in macrophages' integrin β1 or β2, and the subsequent FAK-PI3K/Akt or NF-κB signaling pathway. Collectively, this study highlighted the role of integrins and related signaling pathways in hydrophilic implant-caused macrophage polarization, therefore inventively unveiling the underlying mechanism of NTAP-enhanced osteoimmunomodulation. Furthermore, it established a robust theoretical foundation for the clinical application of this cost-effective, versatile, and transformation-valuable surface engineering strategy for the development of next-generation Ti implants.

Peroxiredoxin 1 modulates oxidative stress resistance and cell apoptosis through stemness in liver cancer under non-thermal plasma treatment

The role of peroxiredoxin 1 (PRDX1), a crucial enzyme that reduces reactive oxygen and nitrogen species levels in HepG2 human hepatocellular carcinoma (HCC) cells, in the regulation of HCC cell stemness under oxidative stress and the underlying mechanisms remain largely unexplored. Here, we investigated the therapeutic potential of non-thermal plasma in targeting cancer stem cells (CSCs) in HCC, focusing on the mechanisms of resistance to oxidative stress and the role of PRDX1. By simulating oxidative stress conditions using the plasma-activated medium, we found that a reduction in PRDX1 levels resulted in a considerable increase in HepG2 cell apoptosis, suggesting that PRDX1 plays a key role in oxidative stress defense mechanisms in CSCs. Furthermore, we found that HepG2 cells had higher spheroid formation capability and increased levels of stem cell markers (CD133, c-Myc, and OCT-4), indicating strong stemness. Interestingly, PRDX1 expression was notably higher in HepG2 cells than in other HCC cell types such as Hep3B and Huh7 cells, whereas the expression levels of other PRDX family proteins (PRDX 2-6) were relatively consistent. The inhibition of PRDX1 expression and peroxidase activity by conoidin A resulted in markedly reduced stemness traits and increased cell death rate. Furthermore, in a xenograft mouse model, PRDX1 downregulation considerably inhibited the formation of solid tumors after plasma-activated medium (PAM) treatment. These findings underscore the critical role of PRDX 1 in regulating stemness and apoptosis in HCC cells under oxidative stress, highlighting PRDX1 as a promising therapeutic target for NTP-based treatment in HCC.

Application and research progress of ARTP mutagenesis in actinomycetes breeding

Atmospheric and room temperature plasma (ARTP) is an emerging artificial mutagenesis breeding technology. In comparison to traditional physical and chemical methods, ARTP technology can induce DNA damage more effectively and obtain mutation strains with stable heredity more easily after screening. It possesses advantages such as simplicity, safety, non-toxicity, and cost-effectiveness, showing high application value in microbial breeding. This article focuses on ARTP mutagenesis breeding of actinomycetes, specifically highlighting the application of ARTP mutagenesis technology in improving the performance of strains and enhancing the biosynthetic capabilities of actinomycetes. We analyzed the advantages and challenges of ARTP technology in actinomycetes breeding and summarized the common features, specific mutation sites and metabolic pathways of ARTP mutagenic strains, which could give guidance for genetic modification. It suggested that the future research work should focus on the establishment of high throughput rapid screening methods and integrate transcriptomics, proteomics, metabonomics and other omics to delve into the genetic regulations and synthetic mechanisms of the bioactive substances in ARTP mutated actinomycetes. This article aims to provide new perspectives for actinomycetes breeding through the establishment and application of ARTP mutagenesis technology, thereby promoting source innovation and the sustainable industrial development of actinomycetes.

The Impact of Helium and Nitrogen Plasmas on Electrospun Gelatin Nanofiber Scaffolds for Skin Tissue Engineering Applications

This study explores the fabrication of tannic acid-crosslinked gelatin nanofibers via electrospinning, followed by helium and nitrogen plasma treatment to enhance their biofunctionality, which was assessed using fibroblast cells. The nanofibers were characterized using scanning electron microscopy, atomic force microscopy, attenuated total reflection Fourier transform infrared spectroscopy, X-ray diffraction, and water contact angle measurements before and after treatment. Helium and nitrogen gas plasma were employed to modify the nanofiber surfaces. Results indicated that helium and nitrogen plasma treatment significantly increased the hydrophilicity and biofunctionality of the nanofibers by 5.1° ± 0.6 and 15.6° ± 2.2, respectively, making them more suitable for human skin fibroblast applications. To investigate the impact of plasma treatment on gelatin, we employed a computational model using density functional theory with the B3LYP/6-31+G(d) method. This model represented gelatin as an amino acid chain composed of glycine, hydroxyproline, and proline, interacting with plasma particles. Vibrational analysis of these systems was used to interpret the vibrational spectra of untreated and plasma-treated gelatin. To further correlate with experimental findings, molecular dynamics simulations were performed on a system of three interacting gelatin chains. These simulations explored changes in amino acid bonding. The computational results align with experimental observations. Comprehensive analyses confirmed that these treatments improved hydrophilicity and biofunctionality, supporting the use of plasma-treated gelatin nanofibers in skin tissue engineering applications. Gelatin's natural biopolymer properties and the versatility of plasma surface modification techniques underscore its potential in regenerating cartilage, skin, circulatory tissues, and hamstrings.

[Mechanism of cold atmospheric plasma in treatment of chronic skin ulcer]

Objective

To review the mechanism of cold atmospheric plasma (CAP) in the treatment of chronic skin ulcer, providing a new idea for ulcer therapy.

Methods

The literature about CAP in the treatment of chronic skin ulcers in recent years was extensively screened and reviewed. The treatment principle, active ingredients, and mechanism were summarized.

Results

CAP is partial ionized gas discharged by plasma generator in high frequency under high voltage. It contains electrons, positive and negative ions, reactive oxygen species, reactive nitrogen species, and ultraviolet rays. In vitro and animal experiments show that the active ingredients contained in CAP can inactive microorganisms, against biofilm, regulate immune-mediated inflammatory, promoting blood flow, stimulate tissue regeneration and epithelial formation in the course of wounds healing.

Conclusion

CAP play a role in different stages of chronic skin ulcer healing, with good effectiveness and safety, and broad clinical application prospects. But more studies are needed to explore the indications and dosages of CAP therapy.

On-Demand Transport Bubbles Adhering to Noncontiguous Patterned Superhydrophobic Surfaces Using a Superhydrophobic Tweezer

Bubble transportation and related flotation are ubiquitous phenomena in nature and industry. Various surfaces with distinct morphologies and specific wettability properties have been engineered by organisms in nature and by humans to facilitate the targeted movement of bubbles. However, existing methods predominantly rely on continuous surfaces, limiting the ability of bubbles to deviate from their path before reaching their intended destination. Therefore, directional transportation of bubbles using noncontiguous surfaces still remains a significant challenge. Inspired by water spiders' ability to capture bubbles underwater using their hydrophobic surface for survival, we propose a novel transport strategy that utilizes patterned superhydrophobic surfaces (PSHSs) and a superhydrophobic tweezer. This strategy is implemented by switching between the hood mode and puncture mode of the moving three-phase contact lines to load and unload the bubble. To quantitatively evaluate the loss ratio of the bubble during transportation, a simple and exquisite bubble-weighing apparatus is devised. Our findings indicate that circular PSHSs demonstrate superior bubble adhesion and achieve the highest bubble transport ratio of 95.1%. In order to validate the promising application of this novel method, we employ the computer numerical control (CNC) technology to facilitate the autonomous loading and precise transportation of underwater bubbles, as well as the blending and ionization of combustible gas bubbles with air bubbles at different volume ratios.

Cold Plasma Technology Based Eco-Friendly Food Packaging Biomaterials

Biopolymers have intrinsic drawbacks compared to traditional plastics, such as hydrophilicity, poor thermo-mechanical behaviours, and barrier characteristics. Therefore, biopolymers or their film modifications offer a chance to create packaging materials with specified properties. Cold atmospheric plasma (CAP) or Low temperature plasma (LTP) has a wide range of applications and has recently been used in the food industry as a potent tool for non-thermal food processing. Though its original purpose was to boost polymer surface energy for better adherence and printability, it has since become an effective technique for surface decontamination of food items and food packaging materials. These revolutionary innovative food processing methods enable the balance between the economic constraints and higher quality while ensuring food stability and minimal processing. For CAP to be considered as a viable alternative food processing technology, it must positively affect food quality. Food products may have their desired functional qualities by adjusting the conditions for cold plasma formation. Cold plasma is a non-thermal method that has little effects on the treated materials and is safe for the environment. In this review, we focus on recent cold plasma advances on various food matrices derived from plants and animals with the aim of highlighting potential applications, ongoing research, and market trends.