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1.
Carbohydr Polym ; 339: 122288, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38823936

ABSTRACT

This paper reports on biofunctionalisation of a poly(lactic acid) (PLA) film by surface activation through cold plasma treatment followed by coating with a chitosan-gelatin xerogel. The UV cross-linking of the xerogel precursor was simultaneously performed with the fixation onto the PLA support. This has a strong effect on surface properties, in terms of wettability, surface free energy, morphology and micromechanical features. The hydrophilic - hydrophobic character of the surface, determined by contact angle measurements, was tuned along the process, passing from moderate hydrophobic PLA to enhanced hydrophilic plasma activated surface, which favors coating adhesion, then to moderate hydrophobic chitosan-gelatin coating. The coating has a Lewis amphoteric surface, with a porous xerogel-like morphology, as revealed by scanning electron microscopy images. By riboflavin mediated UV cross-linking the chitosan-gelatin coating becomes high adhesive and with a more pronounced plasticity, as shown by AFM force-distance spectroscopy. Thus prepared surface-coated PLA supports were successfully tested for growth of dermal fibroblasts, which are known for their induction potential of chondrogenic cells, which is very important in cartilage tissue engineering.


Subject(s)
Chitosan , Fibroblasts , Gelatin , Polyesters , Chitosan/chemistry , Gelatin/chemistry , Polyesters/chemistry , Fibroblasts/drug effects , Fibroblasts/cytology , Humans , Surface Properties , Gels/chemistry , Ultraviolet Rays , Plasma Gases/chemistry , Hydrophobic and Hydrophilic Interactions , Coated Materials, Biocompatible/chemistry , Cross-Linking Reagents/chemistry , Wettability
2.
Chemosphere ; 358: 142211, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38697573

ABSTRACT

This paper investigates the effects of argon (Ar) and that of Ar mixed with ambient air (Ar-Air) cold plasma jets (CPJs) on 4-nitrophenol (4-NP) degradation using low input power. The introduction of ambient air into the Ar-Air plasma jet enhances ionization-driven processes during high-voltage discharge by utilizing nitrogen and oxygen molecules from ambient air, resulting in increased reactive oxygen and nitrogen species (RONS) production, which synergistically interacts with argon. This substantial generation of RONS establishes Ar-Air plasma jet as an effective method for treating 4-NP contamination in deionized water (DW). Notably, the Ar-Air plasma jet treatment outperforms that of the Ar jet. It achieves a higher degradation rate of 97.2% and a maximum energy efficiency of 57.3 gkW-1h-1, following a 6-min (min) treatment with 100 mgL-1 4-NP in DW. In contrast, Ar jet treatment yielded a lower degradation rate and an energy efficiency of 75.6% and 47.8 gkW-1h-1, respectively, under identical conditions. Furthermore, the first-order rate coefficient for 4-NP degradation was measured at 0.23 min-1 for the Ar plasma jet and significantly higher at 0.56 min-1 for the Ar-Air plasma jet. Reactive oxygen species, such as hydroxyl radical and ozone, along with energy from excited species and plasma-generated electron transfers, are responsible for CPJ-assisted 4-NP breakdown. In summary, this study examines RONS production from Ar and Ar-Air plasma jets, evaluates their 4-NP removal efficacy, and investigates the biocompatibility of 4-NP that has been degraded after plasma treatment.


Subject(s)
Argon , Nitrophenols , Plasma Gases , Nitrophenols/chemistry , Argon/chemistry , Plasma Gases/chemistry , Air , Reactive Oxygen Species/metabolism , Water Pollutants, Chemical/toxicity
3.
Chemosphere ; 359: 142230, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38705412

ABSTRACT

This work studied the degradation reaction of sulfonated dyes, indigo carmine, phenol red, and their mixtures by non-thermal plasma (NTP). Interestingly, the degradation rate constant showed a faster process and lower activation energy (Ea) for the dye mixtures than for the degradation reaction of the individual dyes. This unexpected result opened up new opportunities for understanding plasma chemistry and the interaction between reactive species formed by the plasma and the target molecule. As no catalyst or chemical additive was added to the reactor, the decrease in Ea came from a self-synergistic effect (SSE), through the dye molecules fragmentation, which resulted in plasma catalysis. The hypothesis proposed in this work is that oxysulfur (SOx) species are formed by the desulfonation reaction of dyes. The sulfonic groups (SO3) present in the chemical structures of dyes can function as precursors for forming several SOx•- species. Studies based on oxygenated sulfonated species such as SO3•-, SO4•- and SO5•- have been widely applied in advanced oxidative and reductive processes due to their satisfactory efficiency and low cost. Among them, SO4•- is the key reactive species with the best performance in the degradation of pollutants due to its high oxidation potential (E° = 2.60 V). In addition, it is an alternative source of HO• in aqueous media, improving the oxidation reaction. In order to elucidate the SSE, the kinetic process was followed by UV-Vis analysis, and the reactive species, such as alkyl, hydroxyl, and oxy-sulfur radicals were identified by Electron Paramagnetic Resonance. The by-products of the NTP degradation reaction were analyzed by ultrafast liquid chromatography coupled with a mass spectrometer, and a fragmentation route was proposed.


Subject(s)
Coloring Agents , Plasma Gases , Coloring Agents/chemistry , Catalysis , Plasma Gases/chemistry , Oxidation-Reduction , Indigo Carmine/chemistry , Water Pollutants, Chemical/chemistry , Phenolsulfonphthalein/chemistry , Kinetics , Sulfonic Acids/chemistry
4.
PLoS One ; 19(5): e0303931, 2024.
Article in English | MEDLINE | ID: mdl-38820420

ABSTRACT

Spray drying fruit juice powders poses challenges because sugars and organic acids with low molecular weight and a low glass transition temperature inherently cause stickiness. This study employed a hydrophobic polytetrafluoroethylene (PTFE) film to mimic the surface of the drying chamber wall. The Central Composite Design (CCD) using response surface methodology investigated the impact of power (X1, Watt) and the duration of oxygenated plasma treatment (X2, minutes) on substrate contact angle (°), reflecting surface hydrophobicity. To validate the approach, Morinda citrofolia (MC) juice, augmented with maltodextrins as drying agents, underwent spray drying on the improved PTFE-coated surface. The spray drying process for MC juice was performed at inlet air temperatures of 120, 140, and 160°C, along with Noni juice-to-maltodextrin solids ratios of 4.00, 1.00, and 0.25. The PTFE-coated borosilicate substrate, prepared at a radio frequency (RF) power of 90W for 15 minutes of treatment time, exhibited a porous and spongy microstructure, correlating with superior contact angle performance (171°) compared to untreated borosilicate glass. Optimization data indicated that the PTFE film attained an optimum contact angle of 146.0° with a specific combination of plasma RF operating power (X1 = 74 W) and treatment duration (X2 = 10.0 minutes). RAMAN spectroscopy indicated a structural analysis with an ID/IG ratio of 0.2, while Brunauer-Emmett-Teller (BET) surface area analysis suggested an average particle size of less than 100 nm for all coated films. The process significantly improved the powder's hygroscopicity, resistance to caking, and moisture content of maltodextrin-MC juice. Therefore, the discovery of this modification, which applies oxygen plasma treatment to PTFE-coated substrates, effectively enhances surface hydrophobicity, contact angle, porosity, roughness, and ultimately improves the efficacy and recovery of the spray drying process.


Subject(s)
Polytetrafluoroethylene , Polytetrafluoroethylene/chemistry , Surface Properties , Food Handling/methods , Oxygen/chemistry , Fruit and Vegetable Juices , Hydrophobic and Hydrophilic Interactions , Polysaccharides/chemistry , Plasma Gases/chemistry
5.
Food Chem ; 453: 139711, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-38781893

ABSTRACT

The objective of the current work was to evaluate the impacts of dielectric barrier discharge plasma and repeated dry-heat treatments on the acetylation process of corn starch. The combined modification resulted in a higher substitution degree of acetate groups on starch chains compared to the acetylation treatment alone. This outcome was linked to the increase in surface area and structural organization level of granules achieved through the application of plasma and heating/cooling cycles, respectively. The successful esterification of starch structure was verified through FTIR (1710 cm-1) and 1H NMR (2 ppm). With the increase in plasma treatment duration up to 20 min, gelatinization enthalpy increased (10.81 J/g) due to the cross-linking reaction. Starch acetate produced through the combined treatment could find the application in the development of low-calorie food formulations due to its high resistant starch (70.5 g/100 g) and low viscosity (43 mPa s).


Subject(s)
Hot Temperature , Starch , Zea mays , Starch/chemistry , Zea mays/chemistry , Acetylation , Viscosity , Plasma Gases/chemistry
6.
Food Res Int ; 187: 114418, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38763668

ABSTRACT

Interest in exploring alternative starch sources like finger millet is rising due to wide starch applications. However, native starch often lacks desired qualities, including rheological properties. Modification is thus necessary for specific end uses. Plasma treatment as a greener and sustainable method for starch modification was therefore, studied for its ability to impact rheological properties of finger millet starch (FMS). Considerable changes in the rheological properties on FMS was noted, a significant decrease and increase (p < 0.05) in the peak viscosity (from 3.35 to 0.553 Pa.s) and paste clarity respectively was observed, indicating occurrence of depolymerization. However, intermediate plasma-treated samples (200 V) observed a decrease in paste clarity attributed to aggregate formation and cross-linking. Cross-linking was also confirmed by findings of frequency sweep where a continuous decrease in G' values of plasma treated FMS gel was interrupted by sudden increase. Despite depolymerization causing alteration of rheological behaviour such as decrease in shear thinning properties, gel strength observed a contradictory increase. This was attributed to incorporation of functional group and absence of shear responsible for network formation giving higher gel strength to FMS gels. This is elaborated in detail in the study. The study thus concluded that cold plasma significantly impacted all the rheological properties of the FMS and hence can prove to be beneficial for modification of starch rheological parameters.


Subject(s)
Eleusine , Gels , Plasma Gases , Rheology , Starch , Starch/chemistry , Plasma Gases/chemistry , Viscosity , Eleusine/chemistry , Gels/chemistry , Atmospheric Pressure , Food Handling/methods
7.
Biomed Phys Eng Express ; 10(4)2024 May 14.
Article in English | MEDLINE | ID: mdl-38697029

ABSTRACT

Plasma medicine is gaining attraction in the medical field, particularly the use of cold atmospheric plasma (CAP) in biomedicine. The chemistry of the plasma is complex, and the reactive oxygen species (ROS) within it are the basis for the biological effect of CAP on the target. Understanding how the oxidative power of ROS responds to diverse plasma parameters is vital for standardizing the effective application of CAP. The proven applicability of machine learning (ML) in the field of medicine is encouraging, as it can also be applied in the field of plasma medicine to correlate the oxidative strength of plasma-treated water (PTW) according to different parameters. In this study, plasma-treated water was mixed with potassium iodide-starch reagent for color formation that could be linked to the oxidative capacity of PTW. Corresponding images were captured resulting from the exposure of the color-forming agent to water treated with plasma for different time points. Several ML models were trained to distinguish the color changes sourced by the oxidative strength of ROS. The AdaBoost Classifier (ABC) algorithm demonstrated better performance among the classification models used by extracting color-based features from the images. Our results, with a test accuracy of 63.5%, might carry a potential for future standardization in the field of plasma medicine with an automated system that can be created to interpret the oxidative properties of ROS in different plasma treatment parameters via ML.


Subject(s)
Algorithms , Machine Learning , Oxidation-Reduction , Plasma Gases , Reactive Oxygen Species , Water , Plasma Gases/chemistry , Water/chemistry , Color
8.
Talanta ; 275: 126196, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38705018

ABSTRACT

We have developed an innovative optical emission spectrometry imaging device integrating a diode laser for sample introduction and an atmospheric pressure plasma based on dielectric barrier discharge for atomization and excitation. By optimizing the device parameters and ensuring appropriate leaf moisture, we achieved effective imaging with a lateral resolution as low as 50 µm. This device allows for tracking the accumulation of Cd and related species such as K, Zn, and O2+∙, in plant leaves exposed to different Cd levels and culture times. The results obtained are comparable to established in-lab imaging and quantitative methods. With its features of compact construction, minimal sample preparation, ease of operation, and low limit of detection (0.04 µg/g for Cd), this novel methodology shows promise as an in-situ elemental imaging tool for interdisciplinary applications.


Subject(s)
Atmospheric Pressure , Cadmium , Plant Leaves , Cadmium/analysis , Cadmium/chemistry , Plant Leaves/chemistry , Plasma Gases/chemistry , Zinc/chemistry , Zinc/analysis , Spectrum Analysis/methods , Potassium/analysis , Potassium/blood , Potassium/chemistry
9.
Int J Biol Macromol ; 269(Pt 2): 132159, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38719018

ABSTRACT

In recent years, the focus has shifted towards carbohydrate-based hydrogels and their eco-friendly preparation methods. This study involved an investigation into the treatment of wheat starch using dielectric barrier discharge (DBD) plasma technology over varying time gradients (0, 2, 5, 10, 15, and 20 min). The objective was to systematically examine the impact of different treatment durations on the physicochemical properties of wheat starch and the suitability of its gels for 3D printing. Morphology of wheat starch remained intact after DBD treatment. However, it led to a reduction in the amylose content, molecular weight, and crystallinity. This subsequently resulted in a decrease in the pasting temperature and viscosity. Moreover, the gels of the DBD-treated starch exhibited superior 3D printing performance. After a 2-min DBD treatment, the 3D printed samples of the wheat starch gel showed no significant improvements, as broken bars were evident on the surface of the 3D printed graphic, whereas DBD-20 showed better printing accuracy and surface structure, compared to the original starch without slumping. These results suggested that DBD technology holds potential for developing new starch-based gels with impressive 3D printing properties.


Subject(s)
Printing, Three-Dimensional , Starch , Triticum , Triticum/chemistry , Starch/chemistry , Amylose/chemistry , Viscosity , Plasma Gases/chemistry , Molecular Weight , Chemical Phenomena , Temperature
10.
J Am Soc Mass Spectrom ; 35(6): 1227-1236, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38778699

ABSTRACT

Cholesterol is a primary lipid molecule in the brain that contains one-fourth of the total body cholesterol. Abnormal cholesterol homeostasis is associated with neurodegenerative disorders. Mass spectrometry imaging (MSI) technique is a powerful tool for studying lipidomics and metabolomics. Among the MSI techniques, desorption electrospray ionization-MSI (DESI-MSI) has been used advantageously to study brain lipidomics due to its soft and ambient ionization nature. However, brain cholesterol is poorly ionized. To this end, we have developed a new method for detecting brain cholesterol by DESI-MSI using low-temperature plasma (LTP) pretreatment as an ionization enhancement. In this method, the brain sections were treated with LTP for 1 and 2 min prior to DESI-MSI analyses. Interestingly, the MS signal intensity of cholesterol (at m/z 369.35 [M + H - H2O]+) was more than 2-fold higher in the 1 min LTP-treated brain section compared to the untreated section. In addition, we detected cholesterol, more specifically excluding isomers by targeted-DESI-MSI in multiple reaction monitoring (MRM) mode and similar results were observed: the signal intensity of each cholesterol transition (m/z 369.4 → 95.1, 109.1, 135.1, 147.1, and 161.1) was increased by more than 2-fold due to 1 min LTP treatment. Cholesterol showed characteristic distributions in the fiber tract region, including the corpus callosum and anterior commissure, anterior part of the brain where LTP markedly (p < 0.001) enhanced the cholesterol intensity. In addition, the distributions of some unknown analytes were exclusively detected in the LTP-treated section. Our study revealed LTP pretreatment as a potential strategy to ionize molecules that show poor ionization efficiency in the MSI technique.


Subject(s)
Brain Chemistry , Cholesterol , Spectrometry, Mass, Electrospray Ionization , Cholesterol/analysis , Cholesterol/metabolism , Spectrometry, Mass, Electrospray Ionization/methods , Animals , Cold Temperature , Brain/metabolism , Brain/diagnostic imaging , Male , Mice , Plasma Gases/chemistry , Lipidomics/methods
11.
Chemosphere ; 359: 142294, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38734247

ABSTRACT

Development of efficient catalysts for non-thermal plasma (NTP) assisted catalysis to mitigate the formation of harmful by-products is a significant challenge in the degradation of chlorinated volatile organic compounds (Cl-VOCs). In this study, catalytically active Pt nanoparticles supported on non-porous SiO2 and silicalite-1 zeolites (S1) with different pore structure were comparatively investigated for catalytic chlorobenzene degradation under NTP condition. It was shown that the pore structure could significantly impact the metal size and metal dispersion rate. Pt supported on modified S1 hierarchical meso-micro-porous silicalite-1 (Pt/D-S1) exhibited the smallest particle size (∼6.19 nm) and the highest dispersion rate (∼1.87). Additionally, Pt/D-S1 demonstrated superior catalytic performance compared to the other catalysts, achieving the highest chlorobenzene conversion and COx selectivity at about 80% and 75%, respectively. Furthermore, the pore structure also affected the formation of by-products according to the findings from GC-MS analysis. Pt/SiO2 generated a total of 18 different species of organic compounds, whereas only 12 species of organic by-products were identified in the Pt/D-S1 system (e.g. polychlorinated compounds like 3,4 dichlorophenol were exclusively identified in Pt/SiO2). Moreover, dioxin-like polychlorinated biphenyl and other chlorinated organic compounds, which have potential to form highly toxic dioxins, were detected in the catalysts. HRGC-HRMS confirmed and quantified the 17 different dioxin/furans formed on Pt/SiO2 (25,100 ng TEQ kg-1), Pt/S1 (515 ng TEQ kg-1) and Pt/D-S1 (367 ng TEQ kg-1). The correlation between synthesis-structure-performance in this study provides insights into the design of catalysts for deep oxidation of Cl-VOCs in NTP system.


Subject(s)
Chlorobenzenes , Platinum , Polychlorinated Dibenzodioxins , Silicon Dioxide , Chlorobenzenes/chemistry , Catalysis , Platinum/chemistry , Silicon Dioxide/chemistry , Polychlorinated Dibenzodioxins/chemistry , Plasma Gases/chemistry , Zeolites/chemistry , Volatile Organic Compounds/chemistry , Metal Nanoparticles/chemistry , Benzofurans/chemistry
12.
Chemosphere ; 359: 142304, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38734253

ABSTRACT

Toxic organic and heavy metal contaminants commonly exist in industrial waste stream(s) and treatment is of great challenge. In this study, a dielectric barrier discharge (DBD) non-thermal plasma technology was employed for the simultaneous treatment of two important contaminants, chloramphenicol (CAP) and Cr(VI) in an aqueous solution through redox transformations. More than 70% of CAP and 20% of TOC were degraded in 60 min, while Cr(VI) was completely removed in 10 min. The hydroxyl radicals were the main active species for the degradation. Meanwhile, the consumption of hydroxyl radicals was beneficial to the reduction of Cr(VI). The synergistic effect was investigated between CAP degradation and Cr(VI) reduction. The reduction of Cr(VI) would be enhanced in the presence of CAP with a low concentration and could be inhibited under a high concentration, because part of hydroxyl radicals could be consumed by the low-concentration CAP and the obtained intermediates with a higher kinetic rate. However, CAP with a high concentration could react with such reductive species as eaq- and •H, which could compete with Cr(VI) and inhibit the reduction. In addition, the presence of Cr(VI) enhanced the degradation and mineralization of CAP; the study of obtained intermediates indicated that the presence of Cr(VI) changed the degradation path of CAP as Cr(VI) would react with reductive species, enhance the generation of hydroxyl radicals, and cause more hydroxylation reactions. Moreover, the mechanism for the simultaneous redox transformations of CAP and Cr(VI) was illustrated. This study indicates that the DBD non-thermal plasma technology can be one of better solutions for simultaneous elimination of heavy metal and organic contaminants in aquatic environments.


Subject(s)
Chloramphenicol , Chromium , Oxidation-Reduction , Water Pollutants, Chemical , Chloramphenicol/chemistry , Chromium/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/analysis , Plasma Gases/chemistry , Hydroxyl Radical/chemistry , Waste Disposal, Fluid/methods
13.
Int J Biol Macromol ; 270(Pt 1): 132346, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38750859

ABSTRACT

The impact of dual sequential modifications using radio-frequency (RF) plasma and electron beam irradiation (EBI) on starch properties was investigated and compared with single treatments within an irradiation dose range of 5-20 kGy. Regardless of sequence, dual treatments synergistically affected starch properties, increasing acidity, solubility, and paste clarity, while decreasing rheological features with increasing irradiation dose. The molecular weight distribution was also synergistically influenced. Amylopectin distribution broadened particularly below 10 kGy. Amylose narrowed its distribution across all irradiation doses. This was due to dominating EBI-induced degradation and molecular rearrangements from RF plasma. With the highest average radiation-chemical yield (G) and degradation rate constant (k) of (2.12 ± 0.14) × 10-6 mol·J-1 and (3.43 ± 0.23) × 10-4 kGy-1, respectively, upon RF plasma pre-treatment, amylose underwent random chain scission. In comparison to single treatments, dual modification caused minor alterations in spectral characteristics and crystal short-range order structure, along with increased granule aggregation and surface irregularities. The synergistic effect was dose-dependent, significant up to 10 kGy, irrespective of treatment sequence. The highest synergistic ratio was observed when RF plasma preceded irradiation, demonstrating the superior efficiency of plasma pre-treatment in combination with EBI. This synergy has the potential to lower costs and extend starch's technological uses by enhancing radiation sensitivity and reducing the irradiation dose.


Subject(s)
Electrons , Molecular Weight , Plasma Gases , Starch , Starch/chemistry , Plasma Gases/pharmacology , Plasma Gases/chemistry , Solubility , Amylose/chemistry , Amylopectin/chemistry , Rheology
14.
Int J Biol Macromol ; 267(Pt 1): 131435, 2024 May.
Article in English | MEDLINE | ID: mdl-38593900

ABSTRACT

This study represents the inaugural investigation into the effect of cold plasma (CP) pretreatment combined with sodium periodate on the preparation of dialdehyde starch (DAS) from native maize starch and its consequent effects on the properties of DAS. The findings indicate that the maize starch underwent etching by the plasma, leading to an increase in the particle size of the starch, which in turn weakened the rigid structure of the starch and reduced its crystallinity. Concurrently, the plasma treatment induced cleavage of the starch molecular chain, resulting in a decrease in the viscosity of the starch and an enhancement of its fluidity. These alterations facilitated an increased contact area between the starch and the oxidising agent sodium periodate, thereby augmenting the efficiency of the DAS preparation reaction. Consequently, the aldehyde group content was elevated by 9.98 % compared to the conventional DAS preparation methodology. Therefore, CP could be an efficient and environmentally friendly non-thermal processing method to assist starch oxidation for DAS preparation and property enhancement.


Subject(s)
Periodic Acid , Plasma Gases , Starch , Starch/analogs & derivatives , Zea mays , Starch/chemistry , Zea mays/chemistry , Periodic Acid/chemistry , Plasma Gases/chemistry , Viscosity , Oxidation-Reduction , Particle Size
15.
J Environ Sci (China) ; 143: 71-84, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38644025

ABSTRACT

In order to study the degradation process of dioxins in industrial flue gas, the decomposition of o-dichlorobenzene (o-DCB) in a DBD plasma catalytic reactor was investigated. The results showed that an NTP-catalyzed system, especially using the CuMnTiOx catalyst, had better o-DCB degradation performance compared to plasma alone. The combination of the CuMnTiOx catalyst with NTP can achieve a degradation efficiency of up to 97.2% for o-DCB; the selectivity of CO and CO2 and the carbon balance were 40%, 45%, and 85%, respectively. The dielectric constant and electrical property results indicated that the surface discharge capacity of the catalysts played a major role in the degradation of o-DCB, and a higher dielectric constant could suppress the plasma expansion and enhance the duration of the plasma discharge per discharge cycle. According to the O1s XPS and O2-TPD results, the conversion of CO to CO2 follows the M-v-K mechanism; thus, the active species on the catalyst surface play an important role. Moreover, the CuMnTiOx and NTP mixed system exhibited excellent stability, which is probably because Cu doping improved the lifetime of the catalyst. This work can provide an experimental and theoretical basis for research in the degradation of o-DCB by plasma catalyst systems.


Subject(s)
Air Pollutants , Chlorobenzenes , Titanium , Chlorobenzenes/chemistry , Catalysis , Titanium/chemistry , Air Pollutants/chemistry , Models, Chemical , Plasma Gases/chemistry
16.
Food Chem ; 449: 139233, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38593725

ABSTRACT

This investigation was focused on the impact of cold plasma (CP) on the extraction of curcumin and bioactive compounds of turmeric powder (TP). TP was treated with CP at different applied voltages (10, 20, and 30 kV), with various exposure times (10, 20, and 30 min). The curcumin content was highest at 30 kV for 10 min with a yield of 46.49 mg/g of TP. Total phenols significantly (p < 0.05) enhanced from 163.91 to 360.78 mg GAE/g DW accompanied by a remarkable 16% increment in total flavonoids, paralleled by a 26% increment in antioxidants as of control. Nuclear magnetic resonance spectra justified the extraction of curcuminoids. Moreover, micrographs displayed cell lysis in the treated powder. CP has exhibited a positive effect on surface colour parameters and thermal properties of TP. Overall, CP technology can be tailored for better curcumin extraction and the enhancement of phytochemicals.


Subject(s)
Antioxidants , Curcuma , Curcumin , Phytochemicals , Plant Extracts , Plasma Gases , Powders , Curcuma/chemistry , Curcumin/chemistry , Curcumin/pharmacology , Antioxidants/chemistry , Antioxidants/isolation & purification , Plasma Gases/chemistry , Plasma Gases/pharmacology , Phytochemicals/chemistry , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Powders/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification
17.
J Biomater Appl ; 38(10): 1100-1117, 2024 May.
Article in English | MEDLINE | ID: mdl-38580320

ABSTRACT

The surface topological features of bioimplants are among the key indicators for bone tissue replacement because they directly affect cell morphology, adhesion, proliferation, and differentiation. In this study, we investigated the physical, electrochemical, and biological responses of sandblasted titanium (SB-Ti) surfaces with pore geometries fabricated using a plasma electrolytic oxidation (PEO) process. The PEO treatment was conducted at an applied voltage of 280 V in a solution bath consisting of 0.15 mol L-1 calcium acetate monohydrate and 0.02 mol L-1 calcium glycerophosphate for 3 min. The surface chemistry, wettability, mechanical properties and corrosion behavior of PEO-treated sandblasted Ti implants using hydroxyapatite particles (PEO-SB-Ti) were improved with the distribution of calcium phosphorous porous oxide layers, and showed a homogeneous and hierarchically porous surface with clusters of nanopores in a bath containing calcium acetate monohydrate and calcium glycerophosphate. To demonstrate the efficacy of PEO-SB-Ti, we investigated whether the implant affects biological responses. The proposed PEO-SB-Ti were evaluated with the aim of obtaining a multifunctional bone replacement model that could efficiently induce osteogenic differentiation as well as antibacterial activities. These physical and biological responses suggest that the PEO-SB-Ti may have a great potential for use an artificial bone replacement compared to that of the controls.


Subject(s)
Durapatite , Oxidation-Reduction , Surface Properties , Titanium , Titanium/chemistry , Porosity , Durapatite/chemistry , Bone Screws , Animals , Wettability , Materials Testing , Osteogenesis/drug effects , Electrolysis , Plasma Gases/chemistry , Cell Differentiation/drug effects , Corrosion , Biocompatible Materials/chemistry , Osteoblasts/cytology , Mice
18.
Bioresour Technol ; 402: 130756, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38688393

ABSTRACT

DBD low-temperature plasma (DLTP) is recognized as one of the most efficient technologies for treating cotton stalks. This study investigates the impact of various conditions on the gas production characteristics of cotton stalks (CS) and delves into the DLTP decomposition kinetics of CS and CSC in oxygen-enriched (30 % O2/Ar) and CO2 atmospheres. The decomposition rates of CS followed the order CO2 > N2 > Ar. The decomposition behavior of CSC in oxygen-enriched DLTP (30 % O2/Ar) aligned well with the chemical reaction model. The activation energies for CSC decomposition at 900 °C and 1000 °C were determined to be 23.8 kJ/mol and 33.8 kJ/mol, respectively. Moreover, the reaction rate decreased at higher carbonization temperatures, which proved to be detrimental to the decomposition of CSC. The DLTP decomposition of CSC in CO2 exhibited consistency with the fitting results of the unreacted shrinking core model, revealing an observed activation energy of 19.4 kJ/mol.


Subject(s)
Gossypium , Plasma Gases , Gossypium/chemistry , Kinetics , Plasma Gases/chemistry , Carbon Dioxide/chemistry , Temperature , Cold Temperature , Oxygen/chemistry
19.
Biomater Adv ; 161: 213867, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38669824

ABSTRACT

Graphene and graphene oxide (GO), due to their unique chemical and physical properties, possess biochemical characteristics that can trigger intercellular signals promoting tissue regeneration. Clinical applications of thin GO-derived sheets have inspired the development of various tissue regeneration and repair approaches. In this study, we demonstrate that ultrathin sheets of plasma-functionalized and reduced GO, with the oxygen content ranging from 3.2 % to 22 % and the nitrogen content from 0 % to 8.3 %, retain their essential mechanical and molecular integrity, and exhibit robust potential for regenerating bone tissue and blood vessels across multiple cellular and animal models. Initially, we observed the growth of blood vessels and bone tissue in vitro using these functionalized GO sheets on human adipose-derived mesenchymal stem cells and umbilical vein endothelial cells. Remarkably, our study indicates a 2.5-fold increase in mineralization and two-fold increase in tubule formation even in media lacking osteogenic and angiogenic supplements. Subsequently, we observed the initiation, conduction, and formation of bone and blood vessels in a rat tibial osteotomy model, evident from a marked 4-fold increase in the volume of low radio-opacity bone tissue and a significant elevation in connectivity density, all without the use of stem cells or growth factors. Finally, we validated these findings in a mouse critical-size calvarial defect model (33 % higher healing rate) and a rat skin lesion model (up to 2.5-fold increase in the number of blood vessels, and 35 % increase in blood vessels diameter). This study elucidates the pro-osteogenic and pro-angiogenic properties of both pristine and plasma-treated GO ultrathin films. These properties suggest their significant potential for clinical applications, and as valuable biomaterials for investigating fundamental aspects of bone and blood vessel regeneration.


Subject(s)
Bone Regeneration , Graphite , Human Umbilical Vein Endothelial Cells , Mesenchymal Stem Cells , Animals , Graphite/chemistry , Humans , Rats , Bone Regeneration/drug effects , Bone Regeneration/physiology , Mesenchymal Stem Cells/drug effects , Mesenchymal Stem Cells/metabolism , Osteogenesis/drug effects , Osteogenesis/physiology , Mice , Blood Vessels , Rats, Sprague-Dawley , Bone and Bones/blood supply , Bone and Bones/drug effects , Plasma Gases/pharmacology , Plasma Gases/chemistry , Tibia/blood supply , Neovascularization, Physiologic/drug effects , Tissue Engineering/methods
20.
Food Chem ; 450: 139276, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-38626711

ABSTRACT

This study presents a new method combining cold plasma-activated oxygen (CPAO) and microwave (MW) to decontaminate milkshake powder, exploring its effectiveness, mechanisms, and quality impact. CPAO (6 min) alone reduced bacterial load by 0.419 log CFU/g, and MW (3 min) by 0.030 log CFU/g. However, their co-application significantly amplified decontamination, achieving a 1.265 log CFU/g reduction. CPAO-MW co-treatment inflicted more oxidative damage on bacterial cell membranes and intracellular antioxidant defense system, leading to higher mortality. It also raised protein and lipid oxidation, while decreasing vitamin C and A levels in the powder. Specifically, CPAO (6 min)-MW (3 min) co-treatment increased the carbonyl content from 0.438 to 0.891 nmol/mg protein, malondialdehyde from 0.824 to 0.996 mg/kg, and lowered vitamin C from 162.151 to 137.640 mg/kg, and vitamin A from 2.05 to 1.38 mg/kg. This study shows CPAO-MW is effective for decontaminating powdered foods but highlights a need to reduce negative effects.


Subject(s)
Decontamination , Microwaves , Oxygen , Plasma Gases , Powders , Decontamination/methods , Powders/chemistry , Plasma Gases/pharmacology , Plasma Gases/chemistry , Oxygen/metabolism , Animals
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