Effect Of pH Research Articles

Effect of Nutrient Solution pH on the Growth and Quality of Lactuca sativa Grown in a Static Hydroponic System

Lettuce is an easy-to-grow and nutrient-rich leafy vegetable. It grows well using a static hydroponic system, which saves space and is easy to maintain. However, understanding pH’s impact on lettuce growth in static hydroponic systems is limited. Hence, this study was conducted to determine the effect of pH nutrient solution on the growth performance and eating quality of lettuce grown in a static hydroponic system. Lettuce was grown in pH 5.2, 6.2, and 7.2 nutrient solutions. Its growth performance was collected weekly, including plant height, root length, number of leaves, leaf area, leaf chlorophyll content, total dry weight, and total moisture content. The harvested lettuce was analyzed for firmness, soluble solids concentration, titratable acidity, pH, and ascorbic acid content by the fourth week after transplanting. The plant height, root length, number of leaves, leaf area, and total dry weight of lettuce were affected by the interaction between nutrient solution pH and weeks after transplanting. By the third week after transplanting, lettuce grown in pH 6.2 was 11.12 and 18.67% taller than those grown in pH 7.2 and 5.2 nutrient solutions, respectively. By the fourth week after transplanting, the firmness of lettuce grown in pH 6.2 was significantly higher than those grown in pH 5.2 and 7.2 nutrient solutions by 2.34 and 7.32%, respectively. It is concluded that lettuce should be grown in a pH 6.2 nutrient solution when using a static hydroponic system.

Elucidating capabilities of the ZIF-8-Zn metal organic framework as an adsorbent for COD removal of gas refinery wastewater under mild operating conditions

The chemical oxygen demand (COD) of gas refinery wastewater containing discharged ethanolamines and an extent of hydrocarbons was highly reduced utilizing ZIF-8-Zn metal organic framework adsorbent. The mesoporous adsorbent was initially synthesized through hydrothermal method and characterized via FT-IR, XRD, SEM, TEM, EDX, Zeta potential and BET analysis methods. The COD reduction of the wastewater was then followed with effects of pH (5.5–11.5), adsorbent concentration (0.2–2.5 g/L) and contact time (15–110 min). The response surface methodology (RSM) was employed for design of experiments, modelling and optimization of the process. Amazingly, 98.6 % COD reduction was achieved under mild operating conditions of pH 8.3, adsorbent concentration of 1.5 g/L and temperature of 293.2 K after 63 min contact time. A quadratic equation satisfactorily correlated the COD variations versus involved parameters. The data were also precisely correlated with the extended Langmuir isotherm and the mixed 1, 2-order kinetic model implying mono-layer adsorption of the multicomponent adsorbates through physisorption mechanism because of dominant electrostatic interactions. The results of thermodynamic analysis were also consistent with findings. The maximum adsorption capacity of 972.20 mg/g as well as nice reusability in five sequential cycles proved the promising capability of the adsorbent for decontaminating of the gas refinery wastewater.

Eliminating the effect of pH: Dual-matrix modulation adsorbent enables efficient lithium extraction from concentrated seawater

Lithium ion sieve adsorbents frequently extract liquid lithium resources due to their adsorption effect and cost advantages. However, the adsorption effect is significantly influenced by the ambient pH. The pH effects on the adsorption process can be categorized into two main areas: the competition adsorption of impurity ions and the difference in surface zeta potential. A dual-matrix modulation adsorbent was prepared, comprising a carrier matrix modified with zwitterionic quaternary ammonium bases and an adsorption matrix modified with carboxylation. The zwitterionic quaternary ammonium base groups were employed to mitigate the competitive adsorption of impurity ions by acid-base neutralization. Furthermore, the negative charge of carboxyl groups was employed to diminish the discrepancy in surface zeta potential. The adsorption effect of the ion sieve adsorbent under natural conditions appeared to be significantly enhanced by the dual-matrix modulation, with the saturated adsorption capacity (28 mg/g) and adsorption selectivity (α(Li+/Mg2+)=24.23) being 6.3 and 7.8 times higher than that of the manganese-based adsorbent (HMO) under the same conditions, respectively. Moreover, the adsorption effect was found to be consistent with HMO under alkaline conditions. The results demonstrate that by optimizing the adsorption conditions of the adsorbent, the detrimental impact of pH on the adsorption process of lithium ion sieves can be eliminated.

Visible Light-Triggered Catalytic Performance of Reduced Graphene Oxide Decorated With Copper Oxide Nanocomposite for Degradation of Rhodamine B Dye and Kinetics Studies.

Herein, novel nanocomposites based on reduced graphene oxide decorated copper oxide nanoparticles (rGO/CuO) were prepared by the in situ co-precipitation method. The structural, morphological, and optical characterization of as-prepared nanocomposites was performed by powdered x-ray diffraction (p-XRD), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR), Raman, and ultraviolet-visible (UV-Vis) spectroscopy, respectively. The as-prepared nanocomposites exhibited better photocatalytic activity of rhodamine B dye with maximum ~94% degradation in 120 min with a rate constant of 0.2353 min-1 under optimized conditions. Furthermore, the effects of solution pH and catalyst loading are studied on the degradation process. Therefore, this state-of-the-art strategy for the decoration of CuO nanoparticles onto the surface of rGO nanosheets could be an ideal platform for fabricating highly efficient photocatalysts.

Light increases resistance of thylakoid membranes to thermal inactivation.

In the region of slightly acidic pH (рН 5.7), the manganese cluster in oxygen-evolving complex of photosystem II (PSII) is more resistant to exogenous reductants. The effect of such pH on the heat inactivation efficiency of the electron transport chain (O2 evolution and 2,6-dichlorophenolindophenol reduction) in PSII membranes and thylakoid membranes was investigated. Under thylakoid membranes illumination accompanied by lumen acidification, their resistance to heat inactivation increases. In the presence of protonophores, the rate of heat inactivation increases, which seems to be associated not with the protonophore mechanism, but with structural and/or functional changes in membranes. In PSII membrane preparations, the efficiency of the oxygen evolution inhibition at pH 5.7 is also lower than at pH 6.5. The role of reactive oxygen species in thermal inactivation of photosynthetic membranes was investigated using a lipophilic cyclic hydroxylamine ESR spin probe.

B-064 Bovine Serum Albumin Coats Silicon Dioxide More Uniformly Near its Isoelectric Point Based on Atomic Force Microscopy Analysis

Abstract Background Bovine serum albumin (BSA) serves as a blocking agent in in-vitro diagnostic (IVD) applications, with fatty acid stabilized (FAS) and fatty acid free (FAF) BSA as common options. The presence of fatty acids and pH influence the conformation of BSA. While previous studies have explored the individual effects of fatty acids or pH on BSA blocking, limited data exists on their combined impact. This study employs atomic force microscopy (AFM) to investigate how pH and fatty acids jointly affect BSA adsorption onto silica, a surface relevant within diagnostics. Methods AFM, a sensitive microscopic technique, provides topographic images of surfaces with superior resolution compared to optical microscopy. We conducted experiments to assess the adsorption of 1% FAS and FAF BSA on a silica surface at pH 5.2 and pH 7. Evaluation of the coatings involved scratching to assess overall thickness, and roughness, indicating thickness variability. Results Results revealed that both fatty acids and pH play significant roles in shaping the BSA coating characteristics on silica surfaces. In three out of four experimental conditions, the average thickness of the BSA coating ranged between 3-4 nm, except for FAS BSA at pH 7, which exhibited a thicker average coating measuring 5.6 nm. The pH impacted the roughness of the BSA coating. Coatings prepared at pH 5.2 displayed smoother surfaces compared to those at pH 7. Utilizing the root mean square average height variability analysis, there is 95% confidence that the FAF and FAS BSA surfaces at pH 5.2 had a height range between 2.4-4.3 nm and 2.0-4.9 nm, respectively, indicating complete coverage of the silica surface without much height variation. In contrast, the FAF and FAS BSA coatings at pH 7 exhibited a wider range of heights, with 95% confidence intervals spanning from -1.5-8.6 nm and 0.0-11.2 nm, respectively. This variability suggests potential issues including incomplete BSA coverage at the lower range, and steric hindrance at the higher end, highlighting the importance of pH in optimizing BSA coatings for various applications. Conclusions Silica is commonly used in IVD assays, with BSA frequently employed to coat and passivate the surface. Our AFM experiments highlight the impact of pH and fatty acid presence on coating thickness and uniformity. Notably, FAS BSA at pH 7 exhibited the thickest coating; however, its increased roughness may pose challenges in IVD applications due to steric hindrance blocking antibody-antigen interactions. Alternatively, FAF BSA at pH 7 displayed an adequate thickness but also considerable roughness, suggesting potential insufficiencies in surface coverage and passivation. FAS and FAF BSA coatings at pH 5.2 showed relatively consistent thickness, indicating a more uniform surface which may be ideal for IVD coating applications. These AFM experiments were conducted on pure silica surfaces, which may differ from surfaces engineered for IVD. Additionally, both FAF and FAS BSA grades are proven to be effective in IVD applications. Further research employing AFM and other biophysical techniques is warranted to deepen our understanding of pH and fatty acid effects on BSA-surface interactions, aiming to enhance blocking strategies in IVD.

Visible light-induced continuous process for photodegradation of chlorpyrifos using g-C3N4/GO/La2O3 photocatalyst from agricultural aquatic waste

The widespread use of pesticides and the formation of by-products on the gradual decomposition of these pesticides have led to environmental pollution, which in turn has caused harm to both human and ecosystem health. Pesticides have been found in water bodies worldwide and are a cause of concern. Photocatalytic reactions have received significant attention in the past few decades for the breakdown of pesticides. Different parameters were studied, including the effects of pH, kinetics, dose, and regeneration. The UV–vis spectroscopy results suggest that the g-C3N4/GO/La2O3 nanocomposite is a superior reusable photocatalyst for the degradation of chlorpyrifos (CPF) compared to pure g-C3N4 and GO/ g-C3N4. This is demonstrated by the fact that the g-C3N4/GO/La2O3 nanocomposite outperforms both of these materials. The increased photocatalytic performance may be attributed to a balance between the band gap, morphology, crystalline quality, and surface area, all of which may be slowing down the electron-hole recombination rates. This may be due to the enhanced photocatalytic performance. In addition, the feasible processes were outlined from radical quenching studies, and the results clearly indicate that the presence of more OH radicals plays an essential role in the process of efficient photodegradation using novel g-C3N4/GO/La2O3 nanocomposites.

Effects of pH on Polyacrylamide Polymers in Chemical Degradation: A Review

Abstract Chemicals, such as strong oxidant and acid, are generally used for removing the polymer (mainly polyacrylamide polymer) damage in polymer injection wells. The strong oxidant degrades the polymer by breaking polymer molecular chain, but the mechanism of polymer degradation by acid or pH has not been fully studied. Therefore, the previous studies on the effect of pH value on polymers are reviewed in this paper, and the basic principle of oxidative degradation of polymers, the effect of pH on polymer production, and the principle of viscosity reduction of polymers caused by acid solution are emphatically described. A large number of studies have found that the principle of oxidative degradation of polymers is the fracture of polymer molecular chains, and the reduction of polymer viscosity by acid solution does not cause the polymer molecular chains to break, but only makes the polymer molecular chains tightly wound and shrink. The results showed that the effect of pH on polymer viscosity is reversible. The acid solution makes the polymer molecular chain tightly wound and contract by reducing the pH value of the polymer solution, reducing the viscosity of the solution, but the polymer chains are not broken, and by increasing the pH value of the polymer solution through the alkali solution, the viscosity of the solution can be increased, and even the polymer molecular chain can be restored to the original state. So, the oxidant is still essential to degrade polymers. It is unreasonable to evaluate the degradation effect of polymer only based on the change of polymer viscosity. Various factors such as molecular weight and molecular structure should be considered comprehensively through various detection methods. Through the research and discussion of this problem, the relevant experimental research of polymer degradation can be further improved, which provides some new ideas for the research of plugging removal and injection increase in oil Wells, and lays a foundation for plugging removal technology and technology in oil Wells.

Green Synthesis Study: Adsorption of Congo Red Dye with Selenium Nanoparticles Obtained from Prunus Armeniaca L. Leaf Waste

AbstractIn this study, it was aimed to remove Congo Red (CR) dye in aqueous solution by biosynthesized Selenium Nanoparticles from Prunus armeniaca L. (PAL‐SeNPs) leaf wastes by green synthesis method. The characteristic structure of PAL‐SeNPs was determined by UV‐vis spectroscopy, X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscope (SEM), energy dispersive X‐ray (EDX), fourier transform infrared spectroscopy (FTIR), thermogravimetry‐differential thermal analysis (TGA‐DTA), dynamic light scattering (DLS), zetasizer, and point of zero charge (pHpzc). The effects of pH, adsorbent amount, time, initial concentration, and temperature were investigated by batch adsorption studies. 2 different kinetic and 4 isotherm models were tested and error analysis functions were determined for the most suitable model. Accordingly, the particle size, crystallinity, pHpzc value and average surface charge of PAL‐SeNPs were determined as 9.969 nm, 48.50 %, 3.47, and −23.6 mV, respectively. Also, the most suitable kinetic and isotherm models for the removal of CR dye with PAL‐SeNPs were found as Pseudo‐second‐order and Freundlich, with R2 values of 0.996, respectively. Also, where the optimum pH was 7.00, the maximum adsorption capacity was calculated as 96.59 mgCR/gPAL‐SeNPs. The results obtained show that environmentally friendly and low‐cost PAL‐SeNPs produced by the green synthesis method are a suitable alternative for the removal of CR dye.

Effect of Soil-pH, temperature and moisture content on sorption dynamics of Metformin and Erythromycin.

The rising soil-groundwater quality issues due to pharmaceuticals and personal care products (PPCPs) have spurred significant concern. To understand the sorption characteristics of metformin (MTN) and erythromycin (ETM) in sandy and sandy loam soils with varying organic matter and particle composition, sorption kinetics (single and competitive), isotherms, and thermodynamics were studied. The effects of pH and soil moisture content (SMC) were also investigated at environmentally relevant concentrations. The equilibrium time of MTN and ETM sorption by the three soils in a competitive solute system was about 4 h, and the sorption process was in line with a pseudo-second-order model. The rate-determining step in the process involved both intraparticle diffusion and liquid film diffusion mechanisms for the two PPCPs. The highest pollutant uptake occurred in soils with higher organic matter, driven by enhanced H-bonding, electrostatic interactions, and π-π and n-π interactions facilitated by the organic matter. The equilibrium data in the three soils was well described by the Freundlich model and confirmed favourable adsorption (1/nf = 1.01 - 1.90). The sorption coefficient (Kd) on the three soils ranged from 2.1 to 332 L/kg for MTN and from 6.25 to 845 L/kg for ETM. The adsorption process was feasible at 293 K and 303 K (ΔG° = - 0.16 to -10.24 kJ/mol), physical and exothermic in nature (ΔH° = -75.21 to -10.30 kJ/mol) for both the contaminants. Observed alterations in Qe with pH confirmed the participation of electrostatic interactions. A low SMC favoured both MTN and ETM sorption onto the sandy soil. Overall, ETM exhibits higher expected sorption, whereas MTN has a greater tendency for migration in the soils and is thus liable to contaminate the groundwater. The study accentuates novel insights into the transport and fate of MTN and ETM in soil-groundwater systems at environmentally relevant concentrations.

Box-Behnken design optimization of 2D Ti3C2Tx MXene nanosheets as a microwave-absorbing catalyst for methylene blue dye degradation

The 2D MXene Ti3C2Tx was synthesized from the precursor MAX phase Ti3AlC2 by etching the Al layer using hydrofluoric acid. Different Characterization techniques were employed to investigate the properties of the synthesized Ti3C2Tx. The degradation of methylene blue (MB) dye under microwave irradiation in the presence of the prepared 2D MXene was studied. It was found that the synthesized Ti3C2Tx was an excellent microwave catalyst for MB dye degradation, and results obtained were promising. Using this approach, the dye was almost wholly degraded with a degradation efficiency of 99.85 % in only 10 min without adding any oxidant. The degradation was found to follow the pseudo-first-order kinetic model, and the rate constants obtained varied from 0.10 and reached up to 0.67 min−1. The effect of pH, initial MB concentration and catalyst dosage on the MB dye degradation rate has been studied. It was found that carrying out the reaction at pH values ranging from 2 to 10 did not obviously affect its rate. On the other hand, lower initial MB dye concentrations and higher catalyst dosages significantly increased the degradation rate. The high degradation efficiency was found to be maintained for up to five successive catalytic cycles, ensuring the high stability of the synthesized 2D MXene Ti3C2Tx as a catalyst. Optimization of parameters affecting the degradation process was studied using response surface methodology (RSM). According to the Box-Behnken design, the optimal degradation efficiency (99.92 %) could be achieved by adding 21.24 mg of 2D Ti3C2Tx MXene catalyst and using an initial MB dye concentration of 53.06 ppm (mg/L) during a reaction time of 11.93 min.

Adsorption of fluoxetine in aqueous environments: Development of macroporous cryogels based on sodium poly(acrylate) and carboxymethyl chitosan

This study focuses on the development of macroporous monoliths using cryopolymerization of sodium acrylate/carboxymethyl chitosan solutions for the adsorption of the antidepressant fluoxetine in aqueous environments. The cryogels were characterized using various analytical techniques, and the effects of pH, temperature, initial concentration, and contact time on the adsorption capacity were investigated. The surface charge of the cryogel was negative when pHsolution > pHPZC, and pH 8.5 was optimal for swelling rates and fluoxetine removal efficiency. The NaPA4-CMCs cryogel (0.5 mg.mL−1) showed the best adsorption performance, with the pseudo-first-order model best describing the experimental kinetics data. The intraparticle diffusion model revealed rapid diffusion through macropores and mesopores. The Langmuir model fitted well to the experimental adsorption equilibrium data, with qmax = 80.6 ± 3.4 mg.g−1. The adsorption process was favorable, exothermic, and governed by physisorption, involving electrostatic, hydrogen bonding, π–π, and hydrophobic interactions. The binary solvent HCl (0.1 M)/methanol 1:1 v/v was effective for regenerating the adsorbent, with adsorption efficiency greater than 60 % after three cycles of reuse. The study highlights the potential of these macroporous monoliths for the effective removal of antidepressants from aqueous environments.

Phase behavior and interaction of strong polyelectrolyte dextran sulfate and whey protein isolation: Effects of pH, protein/polysaccharide ratio, and salt addition

The strong polyelectrolyte dextran sulfate (DS) is an anionic polysaccharide with a high negative charge, characterized by high stability and pH independence. DS and whey protein isolate (WPI) were selected to study the specific effects of highly negatively charged polysaccharides on the phase behavior and interaction of WPI/DS complexes (1 % w/v) under varying external conditions (pH, WPI:DS ratio, and salt addition). The phase diagrams, zeta potential, and laser confocal scanning microscopy measurements indicated that the WPI/DS complexes did not dissociate even at pH 1 due to the pH independence of DS. The exclusion volume effect of DS promoted WPI self-aggregation at high salt concentrations, which inhibited acidification-induced dissociation. Isothermal titration calorimetry indicated that the WPI/DS interaction is a spontaneous exothermic reaction driven by both enthalpy and entropy changes due to electrostatic interactions. This study provides valuable information on the interactions between highly negatively charged polysaccharides and proteins.

Bi2MoO6/MgIn2S4 S-scheme heterojunction with rich oxygen vacancies for effective organic pollutants degradation: Degradation pathways, biological toxicity assessment, and mechanism research

Designing and constructing novel photocatalysts for organic pollutant degradation is of critical significance for water environment treatment. Constructing a Bi2MoO6/MgIn2S4 (BMO/MIS) S-scheme heterojunction with oxygen vacancies, which efficiently removed RhB within visible light irradiation. Oxygen vacancies regulated the band structure of Bi2MoO6 (BMO) and enhanced the adsorption of RhB on the catalyst's surface. The S-scheme heterojunctions contributed to the separation and transfer of photo-generated charge, retained the optimal redox ability of Bi2MoO6-Vo (BMO-Vo) and MgIn2S4 (MIS) at the same time. X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) further confirmed the S-scheme charge transfer mechanism and the presence of oxygen vacancies. Within 30 min of visible light irradiation, RhB was completely degraded by BMO/MIS-8%, while the degradation efficiency of RhB by BMO-Vo and MIS were only 39.93 % and 80.87 %, respectively. The kinetics constant is 0.1035 min−1 of BMO/MIS-8%, which was 20.29 and 1.95 times that of BMO-Vo and MIS, respectively. At the same time, BMO/MIS-8% achieved removal efficiency of 24.28 %, 56.53 %, 59.15 % and 100 % for MO, TC,H-TC and MB, respectively. Compared to the previously synthesized Bi-ZFO/BMO-Vo photocatalyst, BMO/MIS-8% demonstrated superior degradation efficiency, exhibiting a degradation kinetic constant that was 2.12 times greater than that of Bi-ZFO/BMO-Vo under visible light irradiation. To improve the practical application of BMO/MIS, the effects of pH, co-existing ions and types of pollutants on degradation efficiency were evaluated. In addition, the biological toxicity assessment showed a significant decrease in the toxicity of RhB degradation products. This work provides a feasible avenue for constructing Bi2MoO6-based heterojunctions to treat dye wastewater.

Acid resistance of different polysaccharide hydrocolloids: pH effects

The acid resistance of polysaccharide hydrocolloids is very important for its application in food industry. In this study, the acid resistance of tamarind seed polysaccharide (TSP), xanthan gum (XG), and locust bean gum (LBG) at different pH was investigated. Results showed that the shear viscosity of TSP and LBG was significantly decreased at pH 1. Structural analyses showed that molecular degradation on the side chain of TSP and LBG occurred at pH 1, whereas the composition of the monosaccharides of XG showed no significant difference. Molecular degradation led to a decrease in the molecular weight of TSP and LBG with the gradual decrease of pH, accompanied by a shift in solution conformation, i.e., from semi-flexible chain to rigid rod for TSP and LBG, whereas XG did not undergo significant structural changes with the gradual decrease of pH. In addition, the SEM results showed that with the gradual decrease of molecular weight, the structures of TSP and LBG were gradually broken and showed fragmentation, while XG only showed slight cracks. These results show that the structure of the polysaccharides changes with the gradual decrease of pH, resulting in a change in the solution conformation and a decrease in viscosity. This study provides a new theoretical basis for the application of these polysaccharide hydrocolloids in food processing.

Chitosan extracted from the feather of Dosidicus gigas crosslinked with glutaraldehyde for use as a 99Mo adsorbent

The production of Technetium-99 m (99mTc) is important for cancer diagnosis. The solvent extraction is the most widely used method to obtain 99mTc; however, due to the evaporation of the polluting solvent into the environment, a radiochemical separation using a chromatographic column system based on adsorbent materials would be cleaner and more efficient.In this study, squid feather (Dosidicus gigas) chitosan (SFC) polymers have been synthesized and crosslinked with glutaraldehyde solutions at concentrations of 50, 40 and 25 % to study the adsorption of 99Mo with the aim of test a promising material to produce 99mTc in the chromatographic column of the 99Mo/99mTc generator. Likewise, the same methodology of synthesis was performed using a commercial chitosan (CC) as a control. Deacetylation degree was measured obtaining 74.15 % and 77.65 % for the SFC and CC polymers, respectively. The molecular weight obtained was 990.72 kDa for SFC and 722.72 kDa for CC and the characterization of the biopolymers was performed with FTIR, SEM, XRD, TGA y FT Raman techniques. Equilibrium time, adsorbent mass and pH effect were evaluated as factors that influence the adsorption process of 99MoO4-2. The zero load point (pHPZC) analysis confirmed the positive charge of the crosslinked polymers, improving the adsorption capacity of 99MoO4-2 at low pH values between 2 and 4, following a pseudo-first order model. With respect to the adsorption isotherms, they exhibit maximum values of 99MoO42- of 482 mg g−1 SFCG40 and 502 mg g−1 CCG25 with a better fit to the Langmuir theoretical model.

Effects of thermal processing and pH on the physicochemical properties, stability, and structure of taxifolin-loaded nanostructured lipid carriers

In the present study the potential of nanolipid carriers (transfersomes) for improving the oral delivery of taxifolin, a poorly water-soluble bioactive compound with high antioxidant and anti-inflammatory activity was evaluated. Two transfersome formulations were prepared using lecithin, Span®60, and Tween®80, with cholesterol as a stabilizer (FA) and without cholesterol (FB), by the Ethanol Injection Method (EIM). The influences of thermal treatment (60-90°C) and pH (2, 4, 6, and 8) on physical stability, structure, and taxifolin degradation were evaluated. The transfersomes were physically and chemically stable during heating at lower temperatures (≤70°C), while thermal treatment at 80–90°C led to an increase in particle size (an increase of around 200 nm) and a decrease in taxifolin encapsulation. Moreover, there was no significant difference in particle size or polydispersity index (PDI) at high temperatures. The particle sizes of transfersomes FA and FB increased from 128 and 182 nm at pH 7 to 224 and 331 nm at pH 2, respectively. Both transfersome preparations remained relatively stable, with consistent antioxidant activity (IC50 = 0.64 mg/ml) over four weeks of storage at different temperatures (4, 25, and 40°C), showing higher stability at lower temperatures. The in vitro digestion experiment indicated physical stability after exposure to the simulated stomach stage. However, the reduction in the nanovesicles' surface charge after incubation with gastric juice, increased particle size. Based on these results, taxifolin-loaded transfersomes can be pasteurized at low temperatures, for incorporation into enriched food and beverage products.

Synthesis of various types of green biosorbents materials for removals of sulphates from contaminated water for better aquatic environments

Human and industrial activities pollute water resources with sulphur metal, endangering human health and ecosystems. Chemical precipitation and membrane filtration are expensive when treating large amounts of water, inefficient at low metal concentrations, and produce large amounts of toxic sludge and other products that must be disposed of waste water bio-sorption is eco-friendly and alternative. These methods are cheaper, more accessible, and reusable than conventional ones. This study investigates the bio-sorption of sulphur from contaminated water using neem leaf, custard apple leaf, mango tree leaf, orange peels, and banana peels biological waste materials. This work achieves 100 % removal efficiency. Biosorbents remove sulphates from contaminated water: custard leaves 100 % at 4gm, orange peels 40 % at 5gm, tea waste 50 % at 4gm, neem leaves 70 % at 5gm, and mango leaves 75 % at 5gm. The performances of biosorbents for removals of sulphates from water as follows: Custard leaves waste > Mango leaves > Neem leaves > Tea trash > Orange peels the sulphate reduction by biosorbents. The best biosorption occurred at basic pH 6.5, 3.7gm dosage, 90 min contact duration, 30 °C temperature, and 120 rpm agitation speed. The effects of contact time, agitation speed, adsorbent dosage, pH, and temperature are also examined. Before usage, biosorbents materials can be physically and chemically measured the changes. Regenerating and reusing bio-sorbent after sulphates removals makes the method cost-effective for removals of pollutants from water.

UV-enhanced Fe2+/PDS system for degradation of acid orange 7: Kinetics, degradation mechanism and toxicity assessment

Based on the deficiency of the Fe2+ catalyzed persulfate (PDS) process, ultraviolet (UV) synergistic Fe2+ activated PDS system was introduced in this study for the degradation of acid orange 7 (AO7) dye. The effects of different initial pH, PDS dosage, Fe2+ dosage, and different UV intensities on the degradation rate of AO7 were investigated, and a kinetic model for the apparent reaction rate was determined. The results showed that the UV/ Fe2+/ PDS system was effective in degrading AO7 in a wide pH range. Under optimal conditions, 96 % removal of AO7 was achieved in 10 min. The effects of different inorganic anions on AO7 were discussed; Cl− had little effect on the degradation effect, and SO42−, NO3− and HCO3− inhibited the degradation of AO7 by the system to varying degrees. The presence of reactive radicals (SO4·− and·OH) in the reaction was determined by quenching experiments and EPR capture and their degradation contribution was further investigated. Nine intermediates of AO7 were detected by LC- MS/ MS, and the degradation pathway of AO7 was inferred by combining with UV– Vis spectra. Finally, the ecotoxicity and tritogenic effects of AO7 intermediates were assessed by Toxtree and T.E.S.T toxicity prediction models, which showed that the final degradation product toxicity was non-mutagenic, non-teratogenic, and devoid of hereditary and non-hereditary carcinogenicity.

Development of transition metal oxide platforms for aptasensing of PSA in cell cultures.

In this study, a novel aptasensor based on a transition metal oxide-modified pencil graphite electrode (PGE) was developed for the diagnosis of early-stage prostate cancer (PCa) via monitoring the prostate-specific antigen (PSA), which is the main biomarker for PCa. Single-use PGEs modified with pulsed deposited manganese oxide (MnOx) film were used to attach the amino-terminated aptamer specific to the PSA via carbodiimide chemistry. The designed aptasensor was placed in an electrochemical cell containing ferri/ferrocyanide ions as a redox probe to measure the charge transfer resistances (Rct) of the electrode surface by electrochemical impedance spectroscopy (EIS) to follow the response of each modification step. The effect of the medium pH on the ionic structure of the aptamer molecule according to its pI value and, thus, the reversing of the direction of the response (ΔRct) by the pH change was also discussed. The level of PSA secreted from PCa cells was investigated using impedimetric transduction. The specificity of the aptasensor was validated through selectivity studies against non-specific tumor markers like VEGF and different cancer cell lines including breast cancer and androgen-insensitive prostate cancer. The developed system showcases a label-free, fast, specific, and cost-effective approach for PSA detection, highlighting the importance of medium pH and the electrostatic environment on the aptamer's response. Our work emphasizes the potential for such aptasensors in clinical diagnostics and paves the way for further exploration into using transition metal oxides in biosensing applications.