Plasma Treatment Technique Research Articles

Environmental and economic impact assessment of hydrophobic treatment of cotton using low-pressure-low-temperature plasma

The purpose of this paper is to compare the environmental impact, using Life Cycle Assessment, and the total cost of two hydrophobic fluorocarbon treatment methods: a novel plasma surface modification technique and a traditional pad-dry-curing treatment of fabric. These two techniques have been chosen as two alternatives, with the pad-dry curing being a traditional liquid-based treatment and the plasma treatment a novel gas-based treatment. Such a comparison is a novel effort and will provide to the relevant industrial stakeholders an indication about the sustainability and the financial viability of the plasma treatment technique in comparison to the current state-of-the-art.The Life Cycle Inventory for both techniques has been compiled based on experiments performed at the Technical Textiles Research Centre, using lab scale equipment. The environmental impact has been assessed using the Environmental Footprint 3.0 method and is expressed in micro ecopoints (μPt). The findings have revealed that for plasma treatment (duration of 5 min using 13 cm3/min of C2F6), the environmental footprint is 47% lower than the conventional pad-dry-curing (8.95 μPt per 10 g of treated cotton compared to 18.9 μPt) and the total treatment cost is 81% lower (£1.03 per 10 g of treated cotton compared to £5.47 using pad-dry-curing). The most significant contributor to the environmental performance of the plasma treatment is the electricity consumption, thus a minimization of the treatment time without losing the functionality of the process, and the subsequent operating expenses, will lead to the optimal plasma treatment conditions.

Comprehensive Review on the Impact of Chemical Composition, Plasma Treatment, and Vacuum Ultraviolet (VUV) Irradiation on the Electrical Properties of Organosilicate Films.

Organosilicate glass (OSG) films are a critical component in modern electronic devices, with their electrical properties playing a crucial role in device performance. This comprehensive review systematically examines the influence of chemical composition, vacuum ultraviolet (VUV) irradiation, and plasma treatment on the electrical properties of these films. Through an extensive survey of literature and experimental findings, we elucidate the intricate interplay between these factors and the resulting alterations in electrical conductivity, dielectric constant, and breakdown strength of OSG films. Key focus areas include the impact of diverse organic moieties incorporated into the silica matrix, the effects of VUV irradiation on film properties, and the modifications induced by various plasma treatment techniques. Furthermore, the underlying mechanisms governing these phenomena are discussed, shedding light on the complex molecular interactions and structural rearrangements occurring within OSG films under different environmental conditions. It is shown that phonon-assisted electron tunneling between adjacent neutral traps provides a more accurate description of charge transport in OSG low-k materials compared to the previously reported Fowler-Nordheim mechanism. Additionally, the quality of low-k materials significantly influences the behavior of leakage currents. Materials retaining residual porogens or adsorbed water on pore walls show electrical conductivity directly correlated with pore surface area and porosity. Conversely, porogen-free materials, developed by Urbanowicz, exhibit leakage currents that are independent of porosity. This underscores the critical importance of considering internal defects such as oxygen-deficient centers (ODC) or similar entities in understanding the electrical properties of these materials.

The impact of atmospheric air plasma treatment on the polyfunctional end-use polyester fabric using new synthetic pyrazole dye

Before gluing, bonding, and painting, a variety of materials' surfaces can be modified using the widely used plasma treatment technique. These materials include plastics, glass, metals, and wood. Materials' physical and chemical properties are changed in an environmentally responsible way to enhance or confer particular qualities. The recently used technology known as low-temperature atmospheric pressure plasma (LTAPP) allows heat-sensitive materials to be surface modified in a simple, one-step process. Polymer-based materials are frequently surface modified using LTAPP treatment to improve adhesion, printability, and surface sterility. Polyester's superior mechanical and physical qualities have led to its widespread use as a technical textile and garment material in the form of fibers, films, and plastics. Its limited versatility in terms of end use has been caused by its poor surface properties as the hydrophobic nature of polyester surface, roughness, the crystallinity, and lack of dyeability which are the main drawback restricting its use in different textile applications especially during wet treatments unlike natural fibers. In order to increase the fabric's hydrophilicity and dyeability, the surface of a polyester fabric was altered in this study using atmospheric pressure plasma treatment with atmospheric plasma jet and dielectric barrier discharge (APJ-DBD) technology in air. The primary obstacles in making dielectric barrier discharge (DBD) plasma treatment suitable for industrial purposes are the extended duration of treatment and the utilization of elevated voltage levels. The combination between the atmospheric plasma jet and the dielectric barrier discharge reduces the optimal treatment time to 1 min and the applied voltage to 3.3 kV. After being exposed to oxygen plasma species for a brief period of time (between 30 and 300 s), and were analyzed using an X-ray diffraction machine, an X-ray photoelectron spectroscopy (XPS), static contact angle, and a scanning electron microscope (SEM) to investigate changes in the morphology and chemical nature of the surface, respectively. Fabric wettability increased as a result of plasma treatment, which also increased the fabric's surface roughness, as demonstrated by SEM and X-ray diffraction. The contact angle decreases by increasing the treatment time. The dyeability of untreated and plasma-treated samples was examined with respect to washing, rubbing, perspiration, sublimation, and light fastness. Additionally, color strength was examined. Adequately, compared to the untreated fabric, polyester treated with plasma showed improved dyeing performances. The technical reactivity of poly (ethylene-terephthalate) (PET) fabrics was found to be effectively increased by atmospheric air plasma treatment, creating new avenues for surface modification in light of the expanding environmental and energy-saving concerns.

Sustainable nanocomposite of PAC/Fe3O4-coated geotextile using plasma treatment technique for phenol adsorption application

This study aims to present a novel and enhanced geotextile structure that is simultaneously synthesized and coated employing powder-activated carbon (PAC) and Fe3O4 nanomaterial. Subsequently, the capability of GTX/PAC + Fe3O4 nanocomposite to adsorb phenol pollutants from soil and aqueous environments is investigated in the present study. Although geotextile has been widely used in soil for filtration and barrier applications, no adsorption capacity was reported in the literature. Accordingly, the present study intends to modify the geotextile's surface through plasma technique to improve its hydrophilic properties and effectively bond with the nanocoating composite. To check the performance of the proposed nanocoated-geotextile, various characterization tests are considered, including contact angle, FTIR-ATR, SEM-EDX, and BET. Regarding batch tests, different critical parameters are studied, such as solution pH, the dose of adsorbent, contact time, temperature, and initial concentration on the phenol capacity adsorption. Based on the experimental findings, the proposed nanocoating composite on the geotextile significantly improved the phenol adsorption capacity. Also, various vital parameters were optimized through batch tests with a maximum phenol adsorption capacity of 17.32 mg/g at pH 6 solution, an adsorbent dose of 2.34 gr, a contact time of 75 min, and a concentration of 100 mg/L. Among the isotherm models assessed, the Langmuir model (R2 = 0.99) best fits the experimental results. The kinetics analysis showed that the pseudo-second-order model agreed with the experimental results (R2 = 0.99). The thermodynamic results indicated that the adsorption process in the temperature range of 25–45 °C was spontaneous and exothermic. The GTX/PAC + Fe3O4 nanocomposite showed high recoverability with five consecutive repetitions, maintaining 97.5% of its initial phenol adsorption capacity.

Influence of atmospheric pressure plasma modification on surface properties of aluminum alloy substrate and its interfacial adhesion strength with electrodeposited nickel coating

In the domain of electrodeposited coating applications, the interfacial bonding strength between substrate and Ni-based coatings plays a critical role in determining coating quality and service life. This study investigates the impact of surface physicochemical properties of aluminum alloys on the interfacial bonding strength with electrodeposited nickel, employing a nitrogen/air atmospheric pressure plasma operating at 10 W to modify the substrate surface. The surface microstructure of the substrate remains unaltered following plasma treatment, as evidenced by SEM and AFM images. However, XPS and FTIR-ATR analyses reveal a reduction in carbon content and an increase in polar hydrophilic functional groups, imparting hydrophilicity to the substrate surface. Notably, air plasma treatment proves more effective in modifying the aluminum alloy substrate compared to nitrogen plasma, leading to a super-hydrophilic state with a contact angle of 4.06°. Nano-scratch tests demonstrate a 13.92 % increase in interfacial adhesion strength of Ni-based coatings due to air plasma modification, reaching 14.16 N. This study underscores the considerable potential of plasma treatment techniques to significantly enhance the interfacial adhesion between substrate and electrodeposited nickel, thus presenting promising applications in novel electrodeposited coatings and related fields.

Plasma Modification Techniques for Natural Polymer-Based Drug Delivery Systems.

Natural polymers have attracted significant attention in drug delivery applications due to their biocompatibility, biodegradability, and versatility. However, their surface properties often limit their use as drug delivery vehicles, as they may exhibit poor wettability, weak adhesion, and inadequate drug loading and release. Plasma treatment is a promising surface modification technique that can overcome these limitations by introducing various functional groups onto the natural polymer surface, thus enhancing its physicochemical and biological properties. This review provides a critical overview of recent advances in the plasma modification of natural polymer-based drug delivery systems, with a focus on controllable plasma treatment techniques. The review covers the fundamental principles of plasma generation, process control, and characterization of plasma-treated natural polymer surfaces. It discusses the various applications of plasma-modified natural polymer-based drug delivery systems, including improved biocompatibility, controlled drug release, and targeted drug delivery. The challenges and emerging trends in the field of plasma modification of natural polymer-based drug delivery systems are also highlighted. The review concludes with a discussion of the potential of controllable plasma treatment as a versatile and effective tool for the surface functionalization of natural polymer-based drug delivery systems.

Influence of air plasma modification power on surface properties of basalt fibers and basalt/poly(butylene succinate) adhesion

In this study, basalt fibers were treated with air glow discharge plasma at the powers of 50, 100, 200, and 300 W to investigate the influence of plasma power on fiber surface treatment and basalt/poly(butylene succinate) (PBS) adhesion. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) images showed rougher fiber surfaces when the plasma power was higher than 50 W. Water absorption measurement results demonstrated that the wettability of plasma-treated groups was significantly improved. X-ray photoelectron spectroscopy (XPS) showed that the atomic ratio of O/C increased to 0.91, 1.05, 1.86, and 1.86 for the 50 W, 100 W, 200 W, and 300 W groups, respectively. Tensile testing results of single fibers showed no strength reduction after modification. Microbond pull-out test revealed an increase in the interfacial adhesion of up to 39.2 % between basalt fiber and PBS for the 300 W group. This study demonstrates that our air plasma treatment technique was effective in the modification process for improving the basalt/PBS interfacial adhesion, where the selection of appropriate plasma treatment power was critical.

Experimental analysis and parameter optimization on the reduction of NOx from diesel engine using RSM and ANN Model.

The major emission sources of NOX are from automobiles, trucks, and various non-road vehicles, power plants, coal fired boilers, cement kilns, turbines, etc. Plasma reactor technology is widely used in gas conversion applications, such as NOxconversion into useful chemical by-product. Among the plasma treatment techniques, nonthermal plasma (NTP) is widely used because it does not cause any damage to the surfaces of the reacting chamber. In this proposed work, the feasibility of Dielectric Barrier Discharge (DBD) reactor-based nonthermal plasma (NTP) process is examined based on four operating parameters including NOx concentration (300-400ppm), gas flow rate (2-6 lpm), applied plasma voltage (20-30 kVpp), and electrode gap (3-5mm) for removing NOx gas from diesel engine exhaust. Optimization of NTP process parameters has been carried out using response surface-based Box-Behnken design (BBD) method and artificial neural network (ANN) method and compared with the performance measures such as R2, MSE (mean square error), RMSE (root mean square error), and MAPE (mean absolute percentage error). Two kinds of analysis were carried out based on (1) NOx removal efficiency and (2) energy efficiency. Based on the simulation studies carried out for Nox removal efficiency, the RSM methodology produces the performance measures, 0.98 for R2, 1.274 for MSE, 1.128 for RMSE, and 2.053 for MAPE, and for ANN analysis method, 0.99 for R2, 2.167 for MSE, 1.472 for RMSE, and 1.276 for MAPE. These results shows that ANN method is having enhanced performance measures. For the second case, based on the energy efficiency study, the R2, MSE, RMSE, and MAPE values from the RSM model are 0.97, 2.230, 1.493, and 2.903 respectively. Similarly based on ANN model, the R2, MSE, RMSE, and MAPE values are 0.99, 0.246, 0.46, and 0.615, respectively. From the performance measures, it is found that the ANN model is accurate than the RSM model in predicting the NOx removal/reduction and efficiency. These models demonstrate that they have strong agreement with the experimental results. The experimental results are indicated that optimum conditions arrived based on the RSM model resulted in a maximum NOx reduction of 60.5% and an energy efficiency of 66.24g/J. The comparison between the two models confirmed the findings, whereas this ANN model displayed a stronger correlation to the experimental evidence.

Current Advancements in the Molecular Mechanism of Plasma Treatment for Seed Germination and Plant Growth.

Low-temperature atmospheric pressure plasma has been used in various fields such as plasma medicine, agriculture, food safety and storage, and food manufacturing. In the field of plasma agriculture, plasma treatment improves seed germination, plant growth, and resistance to abiotic and biotic stresses, allows pesticide removal, and enhances biomass and yield. Currently, the complex molecular mechanisms of plasma treatment in plasma agriculture are fully unexplored, especially those related to seed germination and plant growth. Therefore, in this review, we have summarized the current progress in the application of the plasma treatment technique in plants, including plasma treatment methods, physical and chemical effects, and the molecular mechanism underlying the effects of low-temperature plasma treatment. Additionally, we have discussed the interactions between plasma and seed germination that occur through seed coat modification, reactive species, seed sterilization, heat, and UV radiation in correlation with molecular phenomena, including transcriptional and epigenetic regulation. This review aims to present the mechanisms underlying the effects of plasma treatment and to discuss the potential applications of plasma as a powerful tool, priming agent, elicitor or inducer, and disinfectant in the future.

Influence of Plasma Treatment Conditions on Structural-Phase Composition and Magnetic Properties of Barium Hexaferrite (M-type) Films on C-Sapphire

In the work investigated the influence of plasma treatment conditions on the structural-phase composition and magnetic properties of barium hexaferrite films (0001) BaFe12O19 on C-sapphire. Two treatment modes were used: with a weight average plasma temperature of 4-5 kK and 8-10 kK. It has been shown that the films obtained at the low treatment temperature have a pronounced magnetic anisotropy and saturation magnetization of 42 emu/g. The films obtained at high temperature have weak magnetic anisotropy, but have a higher saturation magnetization value of 62 emu/g. All films have low coercive fields of less than 500 Oe, which indicates the low magnetic hardness of barium hexaferrite samples and the possibility of their use as magnetic conductors of transformers, electromagnets, in measuring devices. The presented results demonstrate the promise of the plasma treatment technique in the formation of coatings with high anisotropy. Keywords: barium hexaferrite, sapphire, plasmatron, magnetization.

Влияние условий плазменной обработки на структурно-фазовый состав и магнитные свойства пленок гексаферрита бария (M-типа) на c-сапфире

In the work investigated the influence of plasma treatment conditions on the structural-phase composition and magnetic properties of barium hexaferrite films (0001) BaFe12O19 on C-sapphire. Two treatment modes were used: with a weight average plasma temperature of 4÷5kK and 8÷10kK. It has been shown that the films obtained at the low treatment temperature have a pronounced magnetic anisotropy and saturation magnetization of 42 emu/g. The films obtained at high temperature have weak magnetic anisotropy, but have a higher saturation magnetization value of 62 emu/g. All films have low coercive fields of less than 500 Oe, which indicates the low magnetic hardness of barium hexaferrite samples and the possibility of their use as magnetic conductors of transformers, electromagnets, in measuring devices. The presented results demonstrate the promise of the plasma treatment technique in the formation of coatings with high anisotropy.

Clean surface additive manufacturing of aramid paper-based electrically heated devices for medical therapy application

Flexible thin-film heaters with high heat generation performance and good thermal stability have great potential for medical wearable thermal management applications. However, the current preparation of flexible electrothermal devices mainly uses complex chemical deposition methods, which are interspersed with many environmentally unfriendly chemical wastewaters left by the preparation. In this study, we used water-free plasma treatment and magnetron sputtering techniques to prepare conductive silver/aramid fiber paper (Ag/AFP) flexible thin film heaters. The resultant Ag/AFP sputtered with 6 min exhibited fast thermal response and efficient Joule heating characteristics, reaching 120 °C in less than 6 s at an applied voltage of 1.2 V. Ag/AFP also provided excellent mechanical properties that could withstand bending, folding, and wrinkling without significant loss of electrical and thermal properties. When used in a thermotherapy patch, the Ag/AFP has unique synergistic antibacterial and thermal therapy. The results showed that magnetron sputtering combined with plasma treatment would provide a clean pathway for fabricating wearable textiles/devices.

Rendering viscose fabric dye-able with anionic dyes using plasma treatment technique and chitosan nanoparticles as an eco-friendly approach

PurposeThis paper aims at studying the oxygen plasma treatment and the previously prepared and fully characterized chitosan nanoparticles (CNPs) as a green and eco-friendly strategy for surface modification of viscose fabric. This was done to render viscose fabric dye able with two types of acid dyes that do not have direct affinity to fix on it via improving the fabric wettability.Design/methodology/approachTo achieve the goal, viscose fabric was activated with oxygen plasma at optimum conditions and coated with different concentrations of CNPs solution via conventional pad dry cure technique. The untreated and plasma-treated fabrics with CNPs were dyed with two types of acid dyes, namely, Acid Orange 7 and Methyl Red under determined conditions. The color strength (K/S), fastness properties to light, rubbing and perspiration, add on %, tensile strength, wettability and durability of the dyed samples were determined and compared.FindingsThe results divulged that oxygen plasma-treated fabric with CNPs and the aforementioned dyes in question could improve the flowing properties in comparison with untreated fabric: (a) the fabric wettability expressed as wetting area mm2; (b) the dye ability and fastness properties of viscose fabrics expressed as K/S and fastness properties; and (c) the strength properties and add on % of the treated fabric. On the other hand, the durability of the plasma-treated fabric decreased with increasing washing cycles.Originality/valueThe novelty addressed here was using plasma treatment as an eco-friendly pre-treatment approach for attachment of CNPs as a multifunctional green bio-nano polymer onto viscose fabric, which improved the dyeing properties of the fabric with acid dyes that do not have direct affinity to fix onto it.

Dielectric barrier discharge jet processed TiO2 nanoparticle layer for flexible perovskite solar cells

For attaining good-performance perovskite solar cells (PSCs), the carrier collection from the perovskite material to the transport layer plays a prominent role; herein, we demonstrate an atmospheric pressure plasma treatment technique to enhance the interface properties between the active perovskite layer and electron transport layer (ETL). A scan-mode low-temperature helium dielectric barrier discharge (DBD) jet is applied to process the TiO2 nanoparticle layers for the flexible n-i-p PSCs made on ITO-coated polyethylene naphthalate substrates. When the surface of TiO2 nanoparticle ETL is treated by the DBD jet at a scan rate of 2 cm s−1 and scan height of 5 cm by ten times, the photoelectrical conversion efficiency of the cell is enhanced from 12.30% to 13.66%. The performance improvement can be attributed to the increase of hydrophilic O–C = O functional groups on the surface of the TiO2 nanoparticle layer and the reduction of charge transfer resistance of the cell revealed by x-ray photoelectron spectroscopy and electrochemical impedance spectroscopy, respectively. The results show that the low-temperature DBD jet treatment is a promising technique for processing flexible photovoltaic devices.

Use of Plasma Technologies for Antibacterial Surface Properties of Metals.

Bacterial infections of medical devices present severe problems connected with long-term antibiotic treatment, implant failure, and high hospital costs. Therefore, there are enormous demands for innovative techniques which would improve the surface properties of implantable materials. Plasma technologies present one of the compelling ways to improve metal’s antibacterial activity; plasma treatment can significantly alter metal surfaces’ physicochemical properties, such as surface chemistry, roughness, wettability, surface charge, and crystallinity, which all play an important role in the biological response of medical materials. Herein, the most common plasma treatment techniques like plasma spraying, plasma immersion ion implantation, plasma vapor deposition, and plasma electrolytic oxidation as well as novel approaches based on gaseous plasma treatment of surfaces are gathered and presented. The latest results of different surface modification approaches and their influence on metals’ antibacterial surface properties are presented and critically discussed. The mechanisms involved in bactericidal effects of plasma-treated surfaces are discussed and novel results of surface modification of metal materials by highly reactive oxygen plasma are presented.

Effects of Oxygen Plasma Power on Electrical Characteristics in Multi-Stacked Indium Zinc Oxide Transistors

We report on a method for fabricating solution-processed triple-multi-stacked indium zinc oxide (IZO) thin-film transistors (TFTs) at a low annealing temperature using an oxygen plasma treatment technique at different RF power levels of 120 W, 150 W, 180 W, and 210 W. The oxygen plasma post-treatment is an additional process to optimize the surface state of IZO films and to improve the electrical performance of the TFT device after using a low-temperature solution process instead of a high-temperature annealing process. The plasma-treated TFT device exhibits improved electrical performance, with mobility of 5.1 ± 0.5 cm2/Vs, an on/off ratio of 2.5 × 108, a threshold voltage of 2.6 ± 1.3 V, and a subthreshold swing of 0.6 ± 0.1 V/dec when the RF power is 150 W. Therefore, the multi-stacked activity structure and the low RF power plasma post-treatment process provides a simple and efficient fabrication method that reduces the processing temperature, improves the electrical properties, and can be widely used in flexible electronic devices. Schematic diagrams of the multi-stacked IZO TFT structure, and the oxygen plasmaradiation process with variation of oxygen vacancy before and after treatment.

Production, characterization, activation and environmental applications of engineered biochar: a review

Increased industrial and domestic activities have induced pollution, global warming and resources depletion, calling for advanced remediation techniques. For instance, biochar synthesized from waste materials is an ecofriendly and low-cost material for the remediation of contaminants, yet raw biochar is poorly efficient. Therefore, biochar properties can be improved by ultrasonication, metal impregnation, surfactant modification, microwave, electrochemical and plasma treatment techniques. Biochar properties include adsorption capacity, active surface area, uniform distribution of pores, chemical attributes and mechanical stability. Engineered biochar thus exhibits high contaminant removal efficiency of 90–99%, tolerance to wide range of pH of 3–9 and high specific surface area of more than 400 cm3/g. For example, modified cornstalk biochar displays mercury adsorption capacity of 269.4 mg/g. The usage of magnetic biochar allows a β-estradiol adsorption capacity of 98.8 mg/g. Engineered biochar can act as an ecofriendly soil amendment and a highly efficient tool to recover contaminants from water systems.

Effects of Nonthermal Plasma on Morphology, Genetics and Physiology of Seeds: A Review.

Nonthermal plasma (NTP), or cold plasma, has shown many advantages in the agriculture sector as it enables removal of pesticides and contaminants from the seed surface, increases shelf life of crops, improves germination and resistance to abiotic stress. Recent studies show that plasma treatment indeed offers unique and environmentally friendly processing of different seeds, such as wheat, beans, corn, soybeans, barley, peanuts, rice and Arabidopsis thaliana, which could reduce the use of agricultural chemicals and has a high potential in ecological farming. This review covers the main concepts and underlying principles of plasma treatment techniques and their interaction with seeds. Different plasma generation methods and setups are presented and the influence of plasma treatment on DNA damage, gene expression, enzymatic activity, morphological and chemical changes, germination and resistance to stress, is explained. Important plasma treatment parameters and interactions of plasma species with the seed surface are presented and critically discussed in correlation with recent advances in this field. Although plasma agriculture is a relatively new field of research, and the complex mechanisms of interactions are not fully understood, it holds great promise for the future. This overview aims to present the advantages and limitations of different nonthermal plasma setups and discuss their possible future applications.

Work Function Tuning of Zinc–Tin Oxide Thin Films Using High-Density O2 Plasma Treatment

Work function tuning has a significant influence on the performance of semiconductor devices, owing to the formation of potential barriers at the interface between metal-semiconductor junctions. In this work, we introduce a technique for tuning the work function of ZnSnO thin films using high-density O2 plasma treatment. The work function and chemical composition of the ZnSnO thin film surfaces were investigated with regards to plasma treatment time through UPS/XPS systems. The optical band gap was estimated using Tauc’s relationship from transmittance data. The work function of Zn0.6Sn0.4O thin film increased from 4.16 eV to 4.64 eV, and the optical band gap increased from 3.17 to 3.23 eV. The surface of Zn0.6Sn0.4O thin films showed a smooth morphology with an average of 0.65 nm after O2 plasma treatment. The O2 plasma treatment technique exhibits significant potential for application in high-performance displays in optical devices, such as thin-film transistors (TFTs), light-emitting diodes (LEDs), and solar cells.

Immobilization of gelatin on the oxygen plasma-modified surface of polycaprolactone scaffolds with tunable pore structure for skin tissue engineering

In this study, polycaprolactone (PCL) scaffolds were fabricated via the freeze-casting method. Moreover, the surface of prepared constructs was modified using an oxygen plasma treatment technique for grafting the gelatin in order to improve physicochemical and biological properties. Field emission scanning electron microscopy (FE-SEM) micrographs demonstrated interconnect and unidirectional pore channels. At the same time, the modification procedure showed slight effects on the lamellar microstructure of pores. Fourier transforms infrared (FTIR) spectroscopy determined chemical characterization, which evaluates the effect of the surface treatment on the chemical structure of scaffolds. The wettability of the constructs was investigated by a water drop contact angle and swelling ratio tests. The results illustrated an increment in hydrophilicity after oxygen plasma modification, while the immobilization of gelatin enhanced more the potential of interaction with water molecules. Moreover, the increase in the biodegradation ratio was observed after modification. The in-vitro performance of constructs before and after gelatin immobilization was investigated bt the cell culture assay. Accordingly, modified scaffolds with gelatin support cell attachment and filopodia formation compared with the PCL ones. Besides, the biocompatibility of polymeric matrixes was proved by MTT assay. The results suggest that gelatin grafting on oxygen plasma modified PCL scaffold can be useful in wound healing.