Pressure Plasma Technology Research Articles

Cold Atmospheric Pressure Plasma Technology for Modifying Polymers to Enhance Adhesion: A Critical Review

This review summarizes the results of cold atmospheric pressure plasma technology application in polymers surface treatment. Attention is given to results of changes in the hydrophilic property of polymer surfaces by incorporation of polar functional groups when exposed to atmospheric pressure plasma, depending on the time of treatment, applied voltage, gas flow rate, and distance from the surface. We have successfully developed a plasma device that is able to generate cold atmospheric pressure argon plasma of low temperature (20 – 26) ° C downstream using a high-voltage power source which can be widely used in materials processing. Therefore, a cost-effective system of generating a plasma jet at atmospheric pressure with potential applications has been developed. Cold atmospheric pressure plasma jet (CAPPJ) has shown a lot of applications in recent years such as in materials processing, surface modification, and biomedical materials processing. CAPPJ has been generated by a high voltage (0-20 kV) and high frequency (20-30 kHz) power supply.<br/> The discharge has been characterized by optical and electrical methods. In order to characterize cold atmospheric pressure argon plasma jet, its electron density, electron temperature, rotational temperature, and vibration temperature have been determined using the power balance method, intensity ratio method, Stark broadening method, and Boltzmann plot method, respectively. The improvement in hydrophilicity of the cold plasma-treated polymer samples was characterized by contact angle measurements, surface free energy analysis, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). Contact angle analysis showed that the discharge was effective in improving the wettability of polymers after the treatment. Furthermore, atmospheric plasma can be effectively used to remove surface contamination and to chemically modify different polymer surfaces. The chemical changes, especially oxidation and cross-linking, enhance the surface properties of the polymers.

Fractal microstructure of Ag film via plasma discharge as SERS substrates* *Project supported by the National Natural Science Foundation of China (Grant Nos. 11874140, 12064017, and 61765008), the Science and Technology Project of Changzhou, China (Grant Nos. CJ20210130, CJ20190046, and CJ20200073), and the Postgraduate Research and Practice Innovation Program of Jiangsu Province, China (Grant Nos. B200203143 and KYCX20 0433).

According to the atmospheric pressure plasma (APP) technology, we propose a rapid synthetic approach of the substrates for enhanced Raman spectroscopy. The plasma is used to modify and etch the surface of silver film, which generates large scale hotspots’ aggregation. By switching the discharge polarity and adjusting the film thickness, different surface morphologies are formed due to the oxidation, reactive etch and accumulation of the plasma product in a certain space. Especially under positive corona discharge condition, dense snake-like microstructures are formed by the gradual connection of individual nanoparticles, which are driven by the influence of the electric field on surface diffusion. In addition, the experiments verify that the corresponding enhancement factor (EF) raises at least five orders of magnitude and the treatment time is about 10 min.

Applications of Cold Atmospheric Pressure Plasma Technology in Medicine, Agriculture and Food Industry

In recent years, cold atmospheric pressure plasma (CAPP) technology has received substantial attention due to its valuable properties including operational simplicity, low running cost, and environmental friendliness. Several different gases (air, nitrogen, helium, argon) and techniques (corona discharge, dielectric barrier discharge, plasma jet) can be used to generate plasma at atmospheric pressure and low temperature. Plasma treatment is routinely used in materials science to modify the surface properties (e.g., wettability, chemical composition, adhesion) of a wide range of materials (e.g., polymers, textiles, metals, glasses). Moreover, CAPP seems to be a powerful tool for the inactivation of various pathogens (e.g., bacteria, fungi, viruses) in the food industry (e.g., food and packing material decontamination, shelf life extension), agriculture (e.g., disinfection of seeds, fertilizer, water, soil) and medicine (e.g., sterilization of medical equipment, implants). Plasma medicine also holds great promise for direct therapeutic treatments in dentistry (tooth bleaching), dermatology (atopic eczema, wound healing) and oncology (melanoma, glioblastoma). Overall, CAPP technology is an innovative, powerful and effective tool offering a broad application potential. However, its limitations and negative impacts need to be determined in order to receive regulatory approval and consumer acceptance.

A Study of Anti-Radiation Weaving Fabric with Plasma Corona Treatment

<p>In this research, Carbon black particles were applied on the woven fabric by the knife coating technique and pretreatment using plasma corona discharge to build-up conductive cotton-polyester (CVC 50%) fabric electromagnetic shielding material. This paper describes the making of anti-radiation weaving fabric using plasma technology. The anti-radiation patch was developed by first modifying the textile fabric's surface using atmospheric pressure plasma technology using tip-cylinder electrode configuration. The plasma corona discharge was generated using high voltage electricity with asymmetrical electrodes (tip and cylinder). The treated weaving fabric using plasma was then coated with carbon black ink. This research indicates that an anti-radiation weaving fabric was successfully shielded electromagnetic radiation from an electronic device.</p>

Recent Progress in Applications of Non-Thermal Plasma for Water Purification, Bio-Sterilization, and Decontamination

Various reactive oxygen and nitrogen species are accompanied by electrons, ultra-violet (UV) radiation, ions, photons, and electric fields in non-thermal atmospheric pressure plasma. Plasma technology is already used in diverse fields, such as biomedicine, dentistry, agriculture, ozone generation, chemical synthesis, surface treatment, and coating. Non-thermal atmospheric pressure plasma is also considered a promising technology in environmental pollution control. The degradation of organic and inorganic pollutants will be massively advanced by plasma-generated reactive species. Various investigations on the use of non-thermal atmospheric pressure plasma technology for organic wastewater purification have already been performed, and advancements are continuing to be made in this area. This work provides a critical review of the ongoing improvements related to the use of non-thermal plasma in wastewater control and outlines the operational principle, standards, parameters, and boundaries with a special focus on the degradation of organic compounds in wastewater treatment.

Plasma-Activated Water Modulates Root Hair Cell Density via Root Developmental Genes in Arabidopsis thaliana L.

Low-temperature atmospheric pressure plasma technology has been used in agriculture and plant science by direct and indirect treatment of bio-samples. However, the cellular and molecular mechanisms affected by plasma-activated water (PAW) are largely unexplored. In this study, PAW generated from a surface dielectric barrier discharge (SDBD) device was used for plant development. Physicochemical analysis was performed to confirm the PAW properties that correlated with the plasma treatment time. Arabidopsis thaliana L. was utilized to study the effect of the PAW treatment in the early developmental stage. The plasma-activated water samples are denoted as PAW5 time in minutes (min), PAW7 min, PAW12 min, PAW19 min and PAW40 min with the plasma treatment time. Seedlings grown in the PAW5, PAW7 and PAW12 had increased root lengths while the root lengths were decreased in the PAW19 and PAW40. In the cellular level observation, the PAW treatment specifically increased the root hair numbers per unit of the root but suppressed the root hair length in the PAW, indicating that PAW mainly modulates the root hair cell density in the root. Furthermore, we found that the root hair density and length at PAW5 in maximal observed conditions were positively regulated by root developmental-related genes including COBRA-LIKE9 (COBL9), XYLOGLUCAN ENDOTRANSGLUCOSYLASE/HYDROLASE9 (XTH9), XTH17, AUXIN1 (AUX1) and LIKE-AUXIN (LAX3).

Treatment uniformity of atmospheric pressure plasma on flexible and porous material surface: A critical review

<sec>Flexible porous materials play an important role in frontier science and technology fields. Surface modification will further endow the materials with diverse and excellent surface properties, and expand the scope of their applications in functional and intelligent wearable devices. Atmospheric pressure plasma technology has many advantages in treating the flexible materials, such as low temperature, low energy consumption, high efficiency, friendly environment, low cost, no change in material itself characteristics, suitability for roll-to-roll preparation, etc. Also, it presents good adaptability in applied environment and target materials. All these advantages meet the requirements of large area and low-cost surface modification of flexible porous materials.</sec><sec>In this paper, we review several researches of atmospheric pressure plasma surface modification of flexible porous materials used in advanced materials, new energy, environmental protection and biomedicine. The problems and challenges of stability and permeability encountered in uniformly treating the flexible and porous materials by atmospheric pressure plasma are presented. Then, we introduce our research work on atmospheric pressure plasma stable discharge, roll-to-roll coating treatment of permeability and uniformity. Finally, we introduce the breakthrough in and ideas on the deposition kinetics of nanoparticle thin films and their microstructure control by atmospheric pressure plasma. </sec><sec>However, there are still many challenges to be overcome in the applications of the methods in current situation. Basic characteristics, discharge modes of atmospheric pressure plasma and the relationships of plasma discharge to structure and property of the various treated materials need to be further explored. It is confirmed that the permeability and uniformity of the atmospheric pressure plasma treatment in flexible porous materials are very important and their in-depth investigations will promote the application of this method—a high efficient, environmentally-friendly and continuous way of realizing functional and intelligent wearable devices in the future.</sec>

Surface modification of polyester-cotton (TC 70%) fabric by corona discharged plasma with tip-cylinder electrode configuration-assisted coating carbon black conductive ink for electromagnetic shielding fabric

The study aimed to evaluate corona discharge plasma's effectiveness with tip-cylinder electrode configuration to enhance the coating process for making anti-radiation fabric using coating by carbon black conductive ink. In this research, carbon black conductive ink was applied to various woven fabric types by the knife coating technique and pretreatment using a corona discharged plasma generator to develop an electromagnetic shielding material. The anti-radiation patch fabric was designed by modifying the textile woven fabric's surface using atmospheric pressure plasma technology using tip-cylinder electrode configuration at room temperature, atmospheric pressure, ambient gases, etc.; the plasma-treated woven fabric was then coated with carbon black conductive ink. In this study, the influence of pretreatment of woven fabric by corona discharge plasma as the wetting properties, the surface modification and the value of the anti-radiation electromagnetic field, i.e., E field and H field radiation, were determined and measured by SEM (Scanning Electron Microscope), digital microscope, Fourier Transform Infrared (FTIR) spectrometer, wetting test (using the drop test with AATCC Test Method), and simulation by a computer program. The result of this research indicated that an anti-radiation woven fabric by pretreatment of corona discharged plasma with tip-cylinder electrodes configuration successfully absorbed electromagnetic radiation from smartphone radiation (as the source of radiation). It can be concluded that the current research will be beneficial for the fabrication of various simple and low-cost electromagnetic shielding fabric based on coating by carbon black conductive ink and pretreatment by corona discharged plasma.

Characterization of Cold Atmospheric Pressure Plasma Technology and Its Anticancer Properties

Characterization of Cold Atmospheric Pressure Plasma Technology and Its Anticancer Properties

Application of atmospheric pressure plasma technology for textile surface modification

This paper gives an overview of atmospheric pressure plasma types used in the textile industry and recent developments in plasma treatments of textiles. It investigates the topic of the influence of atmospheric pressure plasma treatment on the surface properties of materials made from natural and synthetic fibers. Through plasma induced physical and chemical reactions occurring in the textile surface layer, significant modifications in micromorphology and reactivity can be achieved. In addition to cleaning, etching, and activation, great efforts have been made in the development of plasma polymerization processes under atmospheric pressure. Utilization of atmospheric pressure plasma technology in the textile industry offers a new perspective on surface modification and functionalization. This paper gives a summary of textile properties achieved using plasma and the underlying processes based on relevant findings obtained from prominent research.

Evaluation of selected microbial and physicochemical parameters of fresh tomato juice after cold atmospheric pressure plasma treatment during refrigerated storage

The Cold Atmospheric pressure Plasma (CAP) technology is an emerging technology used for conditioning and microbiological decontamination of biomaterials including food. A novel tool for inactivation of juice background spoilage microorganisms, as well as high count of inoculated yeast while maintaining physicochemical properties in tomato juice - CAP technology was utilized in this study. Dry matter content and pH were not significantly influenced by CAP generated in GlidArc reactor. Small increase of lycopene, and slight loss of vitamin C content were observed.

Production of Antibacterial Coatings Through Atmospheric Pressure Plasma: a Promising Alternative for Combatting Biofilms in the Food Industry

One of the main problems in the food industry is the formation of biofilms on food contact surfaces. These bacterial communities show high resistance against the commonly used disinfectants, which makes them difficult to eradicate causing economic losses and threatening the quality of the products and the health of consumers. Several studies have reported the use of atmospheric pressure plasma technologies to provide antibacterial properties to a wide range of materials through the deposition of coatings that either avoid the initial attachment of bacteria to the surface or kill the attached bacteria before the mature biofilm is formed. These technologies avoid the use of extreme pressures and temperatures during the deposition process, thus preserving the properties of the substrate, which makes them interesting for their potential application in the production of anti-biofilm food contact materials. This paper reviews different approaches that use atmospheric pressure plasma technologies to combat bacterial colonization and biofilm formation on materials of relevance for the food industry. Three types of approaches are identified and their suitability in the food industry is discussed.

Simultaneous achievement of antimicrobial property and plant growth promotion using plasma‐activated benzoic compound solution

This study assesses a potential use of the recently developed nonthermal atmospheric pressure plasma technology in hydroponic plant cultivation. Two types of plasma‐activated liquid solutions were compared, namely, l‐Phenylalanine (l‐Phe), which had a benzene ring structure, and l‐Alanine (l‐Ala), which did not have a benzene ring structure. Antimicrobial property and plant growth enhancement were simultaneously obtained when plasma‐activated l‐Phe was used. We found that the benzene ring structure in solution contributed to antimicrobial property. Further, colony forming unit assay indicated that 99% of Escherichia coli (E. coli) were eliminated after 24‐h incubation and radish sprout growth increased by about 40% after 2 days of cultivation.

Simple reactor for the synthesis of silver nanoparticles with the assistance of ethanol by gas–liquid discharge plasma

Atmospheric pressure plasma technology is gaining increasing importance because it is a simple and tunable synthesis process for the production of metallic nanoparticles. In addition to the development of the power supply, improving the reactor is also one of the main strategies to enhance the utility. In this study, a simple reactor for the gas–liquid discharge plasma induced by argon gas was applied to synthesize silver nanoparticles from silver nitrate (AgNO3) in solution. An AC power supply with a peak voltage of 3.5 kV was used. The frequency and on-time were set to 50 kHz and 2.5 μs, respectively. The oscilloscope showed that the rising time was approximately 2 μs. The ethanol was used as the source for the reactive reducing agent. No more additional components existed in the solution during the discharge and neither of the electrodes was in contact with the treated solution. The temperature increased by 10 °C within 1 min without a cooling system. Carbon was the main impurity and was expected to be produced from the decomposition of the organics under the plasma. The elevated temperature decreased the organic by-products by evaporation and could also decrease the production of carbon. Transmission electron microscopy showed that the spherical silver nanoparticles with a size of approximately 10 nm were synthesized with a crystal structure and that a low concentration of ethanol prefers the production of the mono-dispersed colloid.

Technologies of plasma treatment of contact lenses

Plasma cleaning is considered to be an accurate cleaning method for high-quality applications in medical production. Differences of low-pressure and atmospheric pressure plasma technologies were analyzed. The main purpose of low-pressure plasma cleaning is the removal of thin organic films from surfaces. The positive effect of plasma treatment on the structure of gas permeable contact lenses surface is described in the article. Plasma cleaning, however, is the most suitable process for achieving optimum surface cleanliness. The given data was obtained by practical means.

(Invited) Atmospheric Pressure Plasma and Depositions of Antibacterial Coatings

Healthcare-associated infections (HCAI) are complications of healthcare that result in elevated patient morbidity and mortality. HCAI present a huge financial burden for patients, hospitals and insurers due to extended hospitalisation and associated care. According to the estimations, in the US alone, HCAI affects approximately 2 million patients annually, of whom approximately 90.000 patients die, with an estimated annual cost estimated to range from 28 billion to 45 billion US$. [1] European Union is facing the similar situation, the European Centre for Disease Prevention and control (ECDC) advice that approximately 4.1 million acute care patients acquire a HCAI annually, with 37.000 deaths directly attributed to HCAI. With increasing prevalence of HCAI across European countries and threatening development of antimicrobial resistance to widely used antibiotics, there is a recognised need for novel approach in battle against this healthcare burden [2]. One of the approaches involves a development and fabrication of materials with antimicrobial properties. Usually, these are coatings with integrated antibacterial agent that is responsible for the elimination of microorganisms that come into contact with active surface. There is a variety of different antibacterial compounds integrated in such coatings, such as different antibiotics, chemical compounds, peptides. Recently, metal nanoparticles (NPs) have been increasingly used in designing coatings with antibacterial properties due to their large surface-to-volume ration, physiochemical properties and biological multi-target mechanism of actions. Besides all beneficial properties of NPs their emergence of cytotoxicity is limiting their practical applications in human body. [3-4] To overcome this drawback it is important to design a new class of antibacterial coatings with firmly embedded NPs that allows controlled release of antimicrobial agent into the microenvironment. Atmospheric pressure plasma technology has shown a big promise as an alternative and cost-efficient method for deposition of coatings with antibacterial properties. This contribution explores the potential of plasma-assisted approach for fabrication of antibacterial coatings, containing different metal NPs on medical textiles. Plasma-assisted deposition of coatings was carried out with so-called ˝sandwich technique˝, where nanoparticles were embedded between two layers in order to tailor the desirable ion release and to prolong antibacterial effect of fabrics. Antibacterial effects of different nano-coatings were tested against G+ and G- bacterial species, Staphylococcus aureus and Escherichia coli, respectively. Besides antibacterial properties, potential cytotoxic effects were also studied. The study demonstrates that atmospheric pressure plasma can be an efficient technique for deposition of antibacterial coatings containing metal NPs. Medical textiles with plasma-assisted nano-coatings showed effective antibacterial properties. The choice of proper metal antimicrobial agent and optimal concentration of NPs should be considered in regards to potential cytotoxic effects when these materials would be used in medical environments. [1] Stone P. Economic burden of healthcare-associated infections: an American perspective. Expert Rev Pharmacoecon and Outcomes Res 2009; 9(5):417-22 [2] Dunne, C. P., Modic, M., et al. anti-microbial coating innovations to prevent infectious diseases (AMiCI) : [commentary] : Cost action ca15114. Bioengineered, ISSN 2165-5979, [in press] 2017, 7 [3] Marambio-Jones C, Hoek EMV. J Nanopart Res., 12(5), 1531-51 (2010). [4] Rai M, Yadav A, Gade A. Biotechnol Adv., 27(1), 76-83 (2009).

Oxygen-radical pretreatment promotes cellulose degradation by cellulolytic enzymes

BackgroundThe efficiency of cellulolytic enzymes is important in industrial biorefinery processes, including biofuel production. Chemical methods, such as alkali pretreatment, have been extensively studied and demonstrated as effective for breaking recalcitrant lignocellulose structures. However, these methods have a detrimental effect on the environment. In addition, utilization of these chemicals requires alkali- or acid-resistant equipment and a neutralization step.ResultsHere, a radical generator based on non-thermal atmospheric pressure plasma technology was developed and tested to determine whether oxygen-radical pretreatment enhances cellulolytic activity. Our results showed that the viscosity of carboxymethyl cellulose (CMC) solutions was reduced in a time-dependent manner by oxygen-radical pretreatment using the radical generator. Compared with non-pretreated CMC, oxygen-radical pretreatment of CMC significantly increased the production of reducing sugars in culture supernatant containing various cellulases from Phanerochaete chrysosporium. The production of reducing sugar from oxygen-radical-pretreated CMC by commercially available cellobiohydrolases I and II was 1.7- and 1.6-fold higher, respectively, than those from non-pretreated and oxygen-gas-pretreated CMC. Moreover, the amount of reducing sugar from oxygen-radical-pretreated wheat straw was 1.8-fold larger than those from non-pretreated and oxygen-gas-pretreated wheat straw.ConclusionsOxygen-radical pretreatment of CMC and wheat straw enhanced the degradation of cellulose by reducing- and non-reducing-end cellulases in the supernatant of a culture of the white-rot fungus P. chrysosporium. These findings indicated that oxygen-radical pretreatment of plant biomass offers great promise for improvements in lignocellulose-deconstruction processes.

Influence of atmospheric pressure argon plasma treatment on the quality of peanut oil

The effects of exposure to atmospheric pressure argon plasma on the quality of edible oil were studied. Peanut oil was exposed to the plasma that was generated in voltages ranging from 150–170 V and the variations of peroxide value, iodine value, acid value, and brightness of the resultant products were monitored. Besides, the storage stability of the radiated peanut oil was investigated as well. Plasma treatment did not change the acid value, but reduced the iodine value and increased the peroxide value and brightness of peanut oil in a voltage‐dependent manner. Compared with control, exposure to the plasma generated in 170 V significantly decreased the contents of oleic acid and linoleic acid by 2.14 and 2.99% respectively, but exhibited no effect on that of palmitic acid. Storage results revealed that the acid value of the treated peanut oils kept increasing in the 30‐day storage period, but the peroxide and iodine values peaked on the 14th and 4th day respectively and then declined gradually. Besides, the voltage‐dependent variation pattern was observed for all the three parameters monitored. Since the peroxide, iodine, and acid values of the treated peanut oil are still in the ranges allowed by the Codex Alimentarius standards, it is concluded that the atmospheric pressure argon plasma treatment does not deteriorate the quality of peanut oil and this technology has potential application in the edible oil industry.A total of 5 mL peanut oil is transferred to a weighing bottle (diameter 40 mm) and exposed to atmospheric pressure argon plasma at a flow rate of 0.5 L/h for 100 s. The voltage of the power supply is set to 150, 155, 160, 165, or 170 V to explore the effects of plasma density on peanut oil quality. Treatment by the plasma generated in voltages 0∼170 V shows no effect on the acid value, but significantly reduces the iodine value, increases the peroxide value, and brightness of peanut oil in a voltage‐dependent manner. Exposure to the plasma generated in 170 V significantly reduces the contents of oleic acid and linoleic acid by 2.14 and 2.99%, respectively, but exhibits no effect on that of palmitic acid.Practical applications: Peanut oil is rich in oleic acid, linoleic acid and other polyunsaturated fatty acids, as well as vitamin E and other nutrients, it also has high nutritional value and pleasant, peculiar flavor. However, aflatoxin B1 (AFB1) which comes from contaminated peanuts is often detected in peanut oil. An alternative that has been presented for the prevention and control of AFs in food is plasma. The plasma is a quasineutral gas of charged and neutral particles which exhibits collective behavior. The domestic and international research indicates that low temperature plasma has a good restraint of tumor cells, the promotion of gene transfection, coagulation and many other aspects. To our knowledge, the report about atmospheric pressure plasma treatment of aflatoxin has not been found in literature. Atmospheric pressure plasma for degradating AFs has the advantages of good safety, high efficiency, environmental friendliness, and is the developing direction of AFs control. In recent years, the development of atmospheric pressure plasma technology have outpaced the traditional low pressure plasma technology because it does not require the use of vacuum equipment, and it shows its advantage of handling large areas of objects more suited to the practical production line. Accordingly, in this paper, acid value, iodine value, peroxide value, chromatic value, fatty acid content and composition, and storage stability are chosen as detection indexes, to study the effects of atmospheric pressure plasma with different voltage on peanut oil quality, in order to provide theoretical basis for the application of atmospheric pressure plasma technology in vegetable oil industry.

Physico-chemical properties of low-pressure plasma treated black gram

Cold plasma technology is an emerging non-thermal food processing technology for microbiological decontamination of food and bio-materials. In the present study, low pressure plasma technology was used as a novel means to modify the surface properties of black gram. The changes imparted on the physico-chemical properties (proximate composition, cooking and textural properties) of black gram was investigated on exposing it to low pressure plasma. The changes in native structure viz., fissures and projections formed on surface were determined by SEM micro-graphs. The cooking time was reduced significantly from 30.25 to 20.45 min with respect to plasma power and treatment durations. Analysis of textural parameters of cooked black gram showed, a decrease in hardness from 22.50 to 12.36 N. SEM micro-graphs confirmed that plasma treatment resulted in surface etching and hydrophilization of surface, allowing easy absorption of water. Extent of hydrophilization was further confirmed by contact angle studies and surface energy analysis. The results showed that plasma treatment decreased the contact angle and increased the surface free energy. Thus, we conclude that low pressure plasma treatment reduces the cooking time of black gram, and perhaps could be employed as an emerging tool for quick cooking process of whole grains.

Terminal sterilization: Conventional methods versus emerging cold atmospheric pressure plasma technology for non‐viable biological tissues

Tissue products are susceptible to microbial contamination from different sources, which may cause disease transmission upon transplantation. Terminal sterilization using gamma radiation, electron‐beam, and ethylene oxide protocols are well‐established and accepted, however, such methods have known disadvantages associated with compromised tissue integrity, functionality, safety, complex logistics, availability, and cost. Non‐thermal (cold) atmospheric pressure plasma (CAP) is an emerging technology that has several biomedical applications including sterilization of tissues, and the potential to surpass current terminal sterilization techniques. This review discusses the limitations of conventional terminal sterilization technologies for biological materials, and highlights the benefits of utilizing CAP.