Sodium Dodecyl Sulfate Research Articles

The effect of Sodium Dodecyl Sulfate on Polysulfone membrane for Pb (II) ions removal in an aqueous solution

The effect of Sodium Dodecyl Sulfate on Polysulfone membrane for Pb (II) ions removal in an aqueous solution

Effect of silver nanoparticles foliar application on the nutritional properties of potato tubers

The aim of presented study was to test nutritional properties of potato tubers and silver ions accumulation pattern after foliar application of silver nanoparticles (AgNPs) during potato vegetation. Potato plants were sprayed with different concentration of Ag nanoparticles (0.1, 1.0 and 10 mg·dm−3) synthesized with incorporation with sodium dodecyl sulphate (SDS) and sodium citrate as stabilizing agent. The lowest amounts of silver ions were transported to the tubers after spraying with AgNPs synthesized with SDS, rather than with citrate. Nevertheless silver ions accumulation in tubers was negligible. SDS method of synthesis was more favourable in terms of nutritional properties of potato tubers. The highest tested concentration of AgNPs_SDS had a favourable effect on a variety of macro- and micronutrients, ascorbic acid and soluble sugars. In turn, lower concentrations of AgNPs_SDS increased the content of phenolic compounds and free radical scavenging efficiency of tubers. These correlations were also confirmed by Principal Component Analysis.

Acptp2,3 participates in the regulation of spore production, stress response, and pigments synthesis in Aspergillus cirstatus

Background Aspergillus cristatus was a filamentous fungus that produced sexual spores under hypotonic stress and asexual spores under hypertonic stress. It could be useful for understanding filamentous fungi’s sporulation mechanism. Previously, we conducted functional studies on Achog1, which regulated the hyperosmotic glycerol signaling (HOG) pathway and found that SI65_02513 was significantly downregulated in the transcriptomics data of ΔAchog1 knockout strain. This gene was located at multiple locations in the HOG pathway, indicating that it might play an important role in the HOG pathway of A. cristatus. Furthermore, the function of this gene had not been identified in Aspergillus fungi, necessitating further investigation. This gene’s conserved domain study revealed that it has the same protein tyrosine phosphatases (PTPs) functional domain as Saccharomyces cerevisiae, hence SI65_02513 was named Acptp2,3. Methods The function of this gene was mostly validated using gene knockout and gene complementation approaches. Knockout strains exhibited sexual and asexual development, as well as pigments synthesis. Morphological observations of the knockout strain were carried out under several stress conditions (osmotic stress, oxidative stress, Congo Red, and sodium dodecyl sulfate (SDS). Real-time fluorescence polymerase chain reaction (PCR) identified the expression of genes involved in sporulation, stress response, and pigments synthesis. Results The deletion of Acptp2,3 reduced sexual and asexual spore production by 4.4 and 4.6 times, demonstrating that Acptp2,3 positively regulated the sporulation of A. cristatus. The sensitivity tests to osmotic stress revealed that ΔAcptp2,3 strains did not respond to sorbitol-induced osmotic stress. However, ΔAcptp2.3 strains grew considerably slower than the wild type in high concentration sucrose medium. The ΔAcptp2,3 strains grew slower than the wild type on media containing hydrogen peroxide, Congo red, and SDS. These findings showed that Acptp2,3 favorably controlled osmotic stress, oxidative stress, and cell wall-damaging chemical stress in A. cristatus. Deleting Acptp2,3 resulted in a deeper colony color, demonstrating that Apctp2,3 regulated pigment synthesis in A. cistatus. The expression levels of numerous stress-and pigments-related genes matched the phenotypic data. Conclusion According to our findings, Acptp2,3 played an important role in the regulation of sporulation, stress response, and pigments synthesis in A. cristatus. This was the first study on the function of PTPs in Aspergillus fungi.

Foam Stabilization Process for Nano-Al2O3 and Its Effect on Mechanical Properties of Foamed Concrete

Foamed concrete is increasingly utilized in engineering due to its light weight, excellent thermal insulation, fire resistance, etc. However, its low strength has always been the most crucial factor limiting its large-scale application. This study introduced an innovative method to enhance the strength of foamed concrete by using nano-Al2O3 (NA) as a foam stabilizer. NA was introduced into a foaming agent containing sodium dodecyl sulfate (SDS) and hydroxypropyl methylcellulose (HPMC) to prepare a highly stable foam. This approach significantly improved the foam stability and the strength of foamed concrete. Its drainage volume, settlement distance, microstructure, and stabilizing action were investigated, along with the strength, microstructure, and hydration products of foamed concrete. The presence of NA effectively reduced the drainage volume and settlement distance of the foam. NA is distributed at the gas–liquid interface and within the liquid film to play a hindering role, increasing the thickness of the liquid film, delaying the liquid discharge rate from the liquid film, and hindering bubble aggregation, thereby enhancing foam stability. Additionally, due to the stabilizing effect of NA on the foam, the precast foam forms a fine and uniform pore structure in the hardened foamed concrete. At 28 d, the compressive strength of FC0 (0% NAs in foam) is 2.18 MPa, while that of FC3 (0.18% NAs in foam) is 3.90 MPa, increased by 79%. The reason for this is that NA promotes the formation of AFt, and its secondary hydration leads to the continuous consumption of Ca(OH)2, resulting in a more complete hydration reaction. This study presents a novel method for significantly improving the performance of foamed concrete by incorporating NA.

Scaling and wetting resistant silica nanoparticle grafted multi-scale corrugated omniphobic membranes for membrane distillation

Membrane distillation (MD) is a promising technology for wastewater treatment, but often faces significant challenges of scaling and wetting. Development of advanced omniphobic membranes has been the core research for mitigating scaling and wetting in MD. In this study, a novel fluorinated multi-scale silicon nanoparticle grafted corrugated (FSiC-PVDF) membrane (water contact angle 179.5 ± 0.3°) was prepared and explored for enhancement of anti-scaling performance by calcium sulfate and anti-wetting performance by sodium dodecylsulfate (SDS). Silica nanoparticles (SiNPs) were synthesized and covalently bonded to the surface of the corrugated membrane and the surface energy was further reduced via chemical fluorination. Flat-sheet membrane (F-PVDF) and corrugated membrane (C-PVDF) were compared. Results showed that compared to the previous study of grafting SiNPs on flat membranes directly, FSiC-PVDF exhibited superior flux (21.1 kg/(m2·h)), and it can consistently demonstrate stable water flux and quality even at high calcium sulfate and SDS concentrations. The F-PVDF experienced significant declines in performance, and the C-PVDF showed limited improvement in scaling and wetting resistance. Corrugation pattern contributed to a larger evaporation area and higher velocity near the membrane surface, thus reducing crystal deposition and heterogeneous nucleation on the surface. The combination of corrugation and SiNPs resulted in a stable Cassie-Baxter wetting state, reduced solid-liquid interface areas, and created slippage conditions that minimized the impact of contaminants on MD performance. These findings indicated that FSiC-PVDF membranes offer significant advantages for MD processes, enhancing operational stability and efficiency.

DPD simulations of anionic surfactant micelles: a critical role for polarisable water models.

We investigate the effects of polarisable water models in dissipative particle dynamics (DPD) simulations, focussing on the influence these models have on the aggregation behaviour of sodium dodecyl sulfate solutions. Studies in the literature commonly report that DPD approaches underpredict the micellar aggregation number of ionic surfactants compared to experimental values. One of the proposed reasons for this discrepancy is that existing water models are insufficient to accurately model micellar solutions, as they fail to account for structural changes in water close to micellar surfaces. We show that polarisable DPD water models lead to more realistic counterion behaviour in micellar solutions, including the degree of counterion disassociation. These water models can also accurately reproduce changes in the dielectric constant of surfactant solutions as a function of concentration. We find evidence that polarisable water leads to the formation of more stable micelles at higher aggregation numbers. However, we also show that the choice of water model is not responsible for the underestimated aggregation numbers observed in DPD simulations. This finding addresses a key question in the literature surrounding the importance of water models in DPD simulations of ionic micellar solutions.

Impacts of different hydrotropes on the aggregation behavior and physicochemical parameters of sodium dodecyl sulfate and ofloxacin drug mixture at several temperatures

Impacts of different hydrotropes on the aggregation behavior and physicochemical parameters of sodium dodecyl sulfate and ofloxacin drug mixture at several temperatures

Dewatering promoting of carbon-rich coal gasification coarse slag by size reduction with surface modification

ABSTRACT Coal gasification coarse slag (CGCS) has become a bulk coal-based solid waste that threatens the ecological environment. The high moisture content of carbon-rich coal coarse gasification slag (CR-CGCS) seriously limits its utilization. In this study, a pore water releasing method was proposed to promote the dewatering of CR-CGCS through size reduction with surface modification. Hexadecyl trimethyl ammonium bromide (CTAB), sodium dodecyl sulfate (SDS), and kerosene were added during the grinding process, respectively. The results showed that kerosene can significantly improve the dewatering efficiency of CR-CGCS more than CTAB and SDS. The final moisture content of the CR-CGCS could be reduced from 47.50% to 33.01%. The SEM and FTIR results illustrated that kerosene could effectively reduce the content of oxygen-containing functional groups on the surface of CR-CGCS more than CTAB and SDS. Meanwhile, the PVM results showed that CR-CGCS modified by kerosene tended to form hydrophobic agglomerates. The LF-NMR results indicated that only the water in the macropores of CR-CGCS could be released in grinding process, but the water in micropores could be reduced when kerosene, CTAB, or SDS was added in grinding. This study provides new insight into enhancing the dewatering of CR-CGCS and theoretical support for the efficient utilization of CR-CGCS.

Surveying the adsorption energy changes of heptane-water-surfactant mixture on the calcite surface using molecular simulation

This study utilized molecular dynamics simulations to examine the impact of surfactant and brine on the interaction between oil and calcite rock. Sodium dodecyl sulfate (SDS) functioned as the surfactant, while NaCl represented the brine, and heptane served as the organic oil phase. The introduction of NaCl led to a decrease in energy between the oil and rock molecules, from 4.18E+03 to 2.36E+03 kcal/mol. This energy reduction was changed to 2.64E+03 kcal/mol by adding surfactant. When both NaCl and SDS were present, the energy dropped to −46.636159 kcal/mol. Through the utilization of radial distribution function and concentration profiles, the study explored the location and buoyancy of heptane molecules on the calcite surface. The results highlighted the efficacy of SDS as an anionic surfactant, particularly in combination with NaCl at a temperature of 373 K, in augmenting the buoyancy of heptane molecules on calcite rock.

Sensitivity assessment of Biomphalaria glabrata (SAY, 1818) using reference substance sodium dodecyl sulfate for ecotoxicological analyzes.

Sodium dodecyl sulfate (SDS) is a surfactant used and recommended by regulatory agencies as a reference substance in ecotoxicological analyzes. In this work, acute toxicity assays were performed with adults and embryos of the freshwater snail Biomphalaria glabrata, an endemic organism with environmental and public health importance, to evaluate the effects of the surfactant and establish a sensitivity control chart. The organisms were exposed to SDS for 24 h to a range of concentrations, as well as a control group. Six assays were performed to establish the control chart for adults (with a median LC50 of 36.87 mg L-1) and differential sensitivity was observed at each embryonic stage (EC50 = blastulae 33.03, gastrulae 35.03, trochophore 39.71 and veliger 72.55 mg L-1). The following behavioral responses were observed in exposed adult snails: release of hemolymph and mucus, body outside the shell, and penile overexposure. Embryos at the blastulae and gastrulae stages were more sensitive, and teratogenic effects were accentuated in the trochophore stage. The difference in results obtained between adults and embryos underscore the importance of carrying out analyzes at different developmental stages. The serial assays established with SDS for B. glabrata demonstrated efficiency and constancy conditions in the assays with good laboratory practice standards. The wide distribution of Biomphalaria species in several countries, their easy maintenance and cultivation in the laboratory, in addition to ecological importance, make them economical alternatives for ecotoxicological assays.

Potential application of SDSO-layered double hydroxide in wastewater treatment: Synergy between hydrophobicity and activation activity

The hydrophobic surface properties of catalysts, generally overlooked in the field of sulfate radical-based advanced oxidation processes (SR-AOPs), have significant potential in enhancing the applicability of catalysts in realistic wastewater treatment. The conflicting nature of hydrophobicity and activation activity presents considerable challenges in developing heterogeneous oxidation. To overcome such limitation, herein, different surfactants were employed to regulate the surface properties of CoCu-layered double hydroxides (LDH) for the activation of peroxymonosulfate (PMS). Our results demonstrated that by comparison with sodium dodecyl sulfate (SDS) and sodium laurate (SLA), sodium dodecyl sulfonate (SDSO) regulated LDH (SDSO-LDH) exhibited the most effective interpolation of organic anions into the interlayer space, simultaneously showing efficient ability for PMS activation and hydrophobicity. The SDSO-LDH/PMS system exhibited excellent degradation performance of various emerging contaminants (ECs), with Co(IV) = O and SO4•- species identified as the dominant oxidative intermediates. Density functional theory (DFT) calculations further confirmed the thermodynamic feasibility of these reactions. Moreover, the effective degradation of intrinsic organic substances in realistic wastewater and sustained hydrophobicity establishes SDSO-LDH a competitive candidate catalyst for SR-AOPs. The synergy between activation activity and hydrophobicity offers a novel perspective for the application of SR-AOPs in wastewater treatment.

Effect of SDS Solutions on the Jamin Effect in a Capillary Tube with a Contracted Throat.

With the continuous exploitation of petroleum resources, the distribution and displacement of residual oils have become key issues in enhancing oil recovery. In a reservoir, there are various forms of residual oils caused by the capillary force, viscous force, and some other hydrodynamic effects, which lead to the Jamin effect, and they restrict the oil displacement process. In this study, the morphologies of oil droplets in a capillary tube laden with water and sodium dodecyl sulfate (SDS) solutions are experimentally investigated. The pinning behavior of the oil droplet is observed in the waterflood with a lower velocity, while depinning and rupturing behaviors occur at a higher velocity. Hereto, we build a mechanics model to analyze the evolution of the Jamin effect in a capillary tube with varying cross sections. Using this theoretical model, we obtain the two critical velocities for the depinning and rupture of the oil droplet, which agree with the experimental results. Moreover, we find that oil droplets can more easily pass through the entire capillary tube in SDS solutions compared with water. The time required for oil droplets to pass through the pore throat becomes shorter with the increase of SDS concentration. Therefore, a theoretical model is established to determine the total pressure difference and the minimum applied pressure difference. These findings are beneficial to obtain a deep insight into the detailed oil displacement and achieve a higher oil recovery rate.

Glycolipopeptide biosurfactant produced by Klebsiella pneumoniae ssp. ozaenae BK34: Virtue in germination and growth of chickpea (Cicer arietinum L.) HC-1 crop

Modern agriculture consumes many persistent and non-biodegradable agrochemicals enhancing production and economy for farmers. Besides, chemical surfactants are used as adjuvant to augment the action of agrochemicals. A toxicity concern of these agrochemicals and adjuvants on life forms and environment cannot be ignored. Microbiologically produced, eco-friendly, biodegradable surfactants could be suggested as an alternative, however, compatibility with plants and beneficial microflora needs to be ascertained before applying them into agriculture. The current study included evaluation of biosurfactant BS34 produced by Klebsiella pneumoniae BK34 towards germination and growth of chickpea [Cicer arietinum (L.)] seeds. The biosurfactant BS34 was characterized as surfactin like glycolipopeptide based on Fourier transform infrared spectroscopy and Liquid chromatography-Mass spectrometry characterization. The biosurfactant was found non-phytotoxic during in-vitro germination of chickpea seeds as evident from very high germination index of 187.74 as opposed to the almost negligible germination index of 0.04 shown by highly phytotoxic chemical surfactant. In comparison to control, the biosurfactant seed treatment [1%(w/v)] in an in-vivo study on chickpea increased the plant height by 18%, nodule number by 11.13%, nodule fresh weight by 12.66% shoot weight by 11.20% and root weight by 34.61%. Contrarily, seed treatment by 1% (w/v) sodium dodecyl sulfate (SDS) inhibited the germination and growth of chickpea seeds again documenting superiority of biosurfactants over their chemical counterparts. Improved seed germination, growth and yield attributes of chickpea crop in presence of non-phytotoxic glycolipopeptide biosurfactant produced by Klebsiella pneumoniae ssp. ozaenae BK34 suggests its potential as an alternative to chemical surfactants used in agriculture.

Effects of Neem Tree Leaf Extract (Azadirachta I Ndica A. Juss) as Defaunating Agent of Sheep (Ovis Aries L.) Fed Napier Grass (Pennisetum Purpureum Schumach)

The effectiveness of neem tree leaf extract (NTLE) as defaunating agent was compared with sodium lauryl sulphate (SLS). Ten (10) sheep was used in the comparison of defaunating agents, the neem tree leaf extract was found to cause fluctuations in ruminal pH, similar to that of sodium lauryl sulphate, effectively reducing protozoal counts (from 296,000 cells/ml to 1,000 cells/ml) and increasing bacterial population (from 10,780 colony forming units/ml to 950,000 colony forming units /ml) in the rumen of sheep. It is therefore strongly advised to use neem tree extract as defaunating agents for sheep fed Napier grass to defaunated sheep in order to maximize food utilization and animal performance.

Effective Detoxification of Olive Mill Wastewater Using Multi-Step Surfactant-Based Treatment: Assessment of Environmental and Health Impact

Olive mill wastewater (OMW) poses a significant environmental challenge and health concern in olive-producing countries, including Jordan. Surfactant micelles are frequently employed as solubilizing agents to enhance the water solubility of chemical compounds. This study aims to leverage the sodium dodecyl sulfate (SDS) micelles in a multi-step process to detoxify OMW for agricultural and industrial uses and reduce its impact. The OMW was treated in multiple steps: screening, coagulation with different chemicals, and distillation with different surfactants. The treatment steps were monitored using LC–MS, GC–MS, ICP–MS, chemical oxygen demand contents, and total phenolic compounds. The detoxification of OMW was evaluated using standard germination assays, MTT assays using tissue culture, and toxicity assays using fluorescence bacteria. Following the treatment, the seed growth rate improved significantly from 0% to 100%. The GC–MS revealed a substantial decrease in pollutants. The concentration of polyphenols was reduced to 2.5%, while the COD level decreased to 35%. The toxicity in bacteria was significantly reduced in a time-dependent manner, and the toxicity in human cells decreased by 95%. Additionally, between 50% and 95% of metals in OMW were removed. The multi-step SDS-based approach successfully detoxified the OMW and enhanced water quality, which would pave the road for its direct application in industry and agriculture.

Spectrofluorimetric determination of tapinarof via Zn (II) complexation and assessment of its topical dosage application

Topical tapinarof is used to treat plaque psoriasis (a skin disease in which red and scaly patches form are appeared on some areas of the body). The goal of the current research is to establish a facile and rapid fluorimetric technique for tapinarof analysis. The approach relied on the reaction between the drug and zinc ion through metal complexation to produce a highly-fluorescent product. The fluorescence was further enhanced by adding sodium dodecyl sulfate, and it was observed at 542 nm following excitation at 497 nm. With a correlation coefficient of 0.9997, the association between emission intensity and tapinarof concentration was linear between 2.0 and 120 ng mL−1. 1.021 ng mL−1 was the quantitation limit while 0.366 ng mL−1 was the detection limit. The buffer type, pH and concentration, type of surfactant and concentration, and finally the diluting solvent were among the reaction conditions that were closely examined and it was found that the optimum conditions were obtained upon employing teorell-stenhagen buffer optimized at pH 6.0, 1.38 × 10–2 M SDS and distilled water as a solvent are the suitable choice. With great precision and reliability, the drug under study was quantified using this method in ointment formulations. The proposed method's level of greenness was assessed using two methodologies: the analytical greenness metric (AGREE) and the Green Analytical Procedure Index (GAPI), with good recovery results ensuring high efficiency of the proposed approach on analysis of ointment without any interference from additives and excipients.

The effects of dissolved organic carbon and model compounds (DOC analogues) on diffusive water flux, oxygen consumption, nitrogenous waste excretion rates and gill transepithelial potential in Pacific sanddab (Citharichthys sordidus) at two salinities.

Many flatfish species are partially euryhaline, such as the Pacific sanddab which spawn and feed in highly dynamic estuaries ranging from seawater to near freshwater. With the rapid increase in saltwater invasion of freshwater habitats, it is very likely that in these estuaries, flatfish will be exposed to increasing levels of dissolved organic carbon (DOC) of freshwater origin at a range of salinities. As salinity fluctuations often coincide with changes in DOC concentration, two natural freshwater DOCs [Luther Marsh (LM, allochthonous) and Lake Ontario (LO, autochthonous) were investigated at salinities of 30 and 7.5 ppt. Optical characterization of the two natural DOC sources indicate salinity-dependent differences in their physicochemistry. LO and LM DOCs, as well as three model compounds [tannic acid (TA), sodium dodecyl sulfate (SDS) and bovine serum albumin (BSA)] representing key chemical moieties of DOC, were used to evaluate physiological effects on sanddabs. In the absence of added DOC, an acute decrease in salinity resulted in an increase in diffusive water flux (a proxy for transcellular water permeability), ammonia excretion and a change in TEP from positive (inside) to negative (inside). The effects of DOC (10mg C L-1) were salinity and source-dependent, with generally more pronounced effects at 30 than 7.5 ppt, and greater potency of LM relative to LO. Both LM DOC and SDS increased diffusive water flux at 30 ppt but only SDS had an effect at 7.5 ppt. TA decreased ammonia excretion at 7.5 ppt. LO DOC decreased urea-N excretion at both salinities whereas the stimulatory effect of BSA occurred only at 30 ppt. Likewise, the effects of LM DOC and BSA to reduce TEP were present at 30 ppt but not 7.5 ppt. None of the treatments affected oxygen consumption rates. Our results demonstrate that DOCs and salinity interact to alter key physiological processes in marine flatfish, reflecting changes in both gill function and the physicochemistry of DOCs between 30 and 7.5 ppt.

Composite of Organo-LDH and biochar for diclofenac sodium removal from aqueous solutions

Classic layered double hydroxides (LDHs) and their composites with biochar are promising adsorbents for removing emerging contaminants like diclofenac sodium (DFS) from water. However, the use of organo-LDHs in these composites remains unexplored and could enhance their adsorption properties for organic molecules. This study investigates the synthesis, characterization, and application of an organo-LDH based on sodium dodecyl sulfate as intercalating agent (SDS-LDH) and its composite with tangerine peel biochar (SDS-LDH/BC) for the removal of DFS from water. The adsorption performance of these materials was compared with those of a composite of SDS-LDH and tangerine peel biomass (SDS-LDH/Bio) and the layered double oxides (LDOs) obtained from the pyrolysis of SDS-LDH and SDS-LDH/Bio, referred to as SDS-LDO and SDS-LDO/Bio, respectively. The materials were characterized by FTIR, XRD, SEM, TG, and pH point of zero charge analyses, and the adsorption of DFS was evaluated in aqueous medium under different conditions. XRD and FTIR demonstrated the successful incorporation of sodium dodecyl sulfate into the interlamellar space of the SDS-LDH, which was preserved in the SDS-LDH/BC and SDS-LDH/Bio composites. SEM analysis revealed that the SDS-LDH structures, with varied shapes and sizes, were dispersed on the matrix of the biochar, while TG analysis showed that the SDS-LDH/BC had similar thermal stability to SDS-LDH. SDS-LDH achieved 90 % DFS removal at pH 8.0 and 25 °C, while SDS-LDH/BC reached 81 % removal under the same conditions, with maximum DFS adsorption capacities of 247 and 169 mg g−1, respectively, outperforming pristine biochar (no removal). Under the same conditions, SDS-LDH/Bio, SDS-LDO/Bio, and SDS-LDO removed 55 %, 36 %, and 36 % of DFS, respectively. These results revealed the pivotal role of the interlamellar structure of SDS-LDH in DFS adsorption, as confirmed by XRD and FTIR, which indicated that DFS interacted with dodecyl sulfate anion in the SDS-LDH interlamellar space, specially through hydrophobic interaction. Kinetics studies revealed that DFS adsorption on SDS-LDH/BC followed the pseudo-first-order model, while adsorption on SDS-LDH followed the pseudo-second-order model, with equilibrium reached in approximately 30 min. The Redlich-Peterson model satisfactorily fitted the adsorption equilibrium isotherms for both SDS-LDH and SDS-LDH/BC. Although no synergistic effect was observed between biochar and SDS-LDH/BC regarding the adsorption capacity, the formation of the SDS-LDH/BC composite improved the preservation of the SDS-LDH structures, allowing for a lower loss of adsorption capacity upon reuse. These findings suggest that the study of such advanced material can contribute to the development of more effective biochar-LDH composite-based adsorbents, specifically for the removal of organic pollutants.

Springtail-inspired omniphobic slippery membrane with nano-concave re-entrant structures for membrane distillation

Omniphobic membranes, due to their exceptional properties, have drawn significant attention for overcoming the bottleneck in membrane distillation (MD) technology. This study demonstrates an innovative method for fabricating an omniphobic membrane that is simple and facile compared to other methods such as wet/dry etching and photolithography. The surface morphology of springtails was imitated using electrospraying technique to coat a polyvinylidene fluoride substrate with concave-shaped polystyrene beads that were successfully developed by controlling the electrical traction (voltage) and air resistance (humidity). Then, the lipid coating of springtail surfaces was mimicked by dip-coating the membrane in a low-toxicity short-chain perfluoropolyether lubricant. The concave structure’s tiny air pockets increased membrane hydrophobicity significantly, indicated by the fact that the first round of water bouncing took only 16.3 ms. Finally, in MD treatment of seawater containing 1.0 mM sodium dodecyl sulfate, the optimized omniphobic membrane maintained a stable 99.9% salt rejection rate.

Modifying physicochemical properties, rheology, and creaming stability of milk fat globule and membrane through ultrasound treatment

The healthy benefits of milk fat globules and membrane (MFGs/MFGM) ingredients are increasingly recognized in the dairy industry. In this research, we examined the effects of ultrasonic treatment on the physicochemical and rheological properties, as well as the emulsions stability of MFGs/MFGM derived from bovine raw milk. Fresh milk was subjected to sonication at frequencies of 20 kHz and 40 kHz, either individually or simultaneously, for durations of 5 min or 15 min, using work/rest cycles of 5 s on and 3 s off. Bovine milk, without any treatment, served as the control. Regardless of the intensity difference, ultrasonic treatment for 5 min resulted in more pronounced changes in the regions of Amide Ⅱ (1600–1500 cm−1), Amide Ⅲ (1500–1200 cm−1), and fingerprint region (1200–1900 cm−1) compared to both the 15 min treatments and control MFGs/MFGM. Principal component analysis (PCA) conducted on the entire spectra, as well as in the regions of Amide Ⅰ, Amide Ⅱ, and the fingerprint spectra, clustered the 5 min treatment distinctly from the control and MFGs/MFGM ultrasonically treated for 15 min. MFGs/MFGM samples following 20 kHz and 40 kHz synchronous treatment for 15 min exhibited lower absorbance bands at 1727–1726 cm−1, whereas a higher content at 1740 cm−1 was observed compared to control MFGs/MFGM. Additionally, a more significant reduction in the intramolecular β-sheet content in 20 + 40 kHz/ 15 min treatment was observed. According to the sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) patterns, a diminished intensity of Periodic Acid Schiff 6/7 (PAS 6/7) bands was observed across all the MFGs/MFGM. Ultrasonic treatment retained more caseins while reducing the β –LG levels compared to the controls, enhancing the stability of MFGs/MFGM, except in MFGs/ MFGM subjected to 20 and 40 kHz simultaneously treated for 15 min. The irregular sphericity of fat globules was noted particularly in MFGs/MFGM treated at 20 kHz independently or in combination with 40 kHz for 15 min. According to the confocal laser scanning microscopy (CLSM), ultrasonic treatment facilitated the binding of caseins or whey proteins to the MFGs surface and induced flocculation of membrane proteins. Hierarchical cluster analysis (HCA) heat map further underscored the impact of ultrasonic treatments on the structural and compositional changes, as well as rheology and emulsions stability, of MFGs/MFGM.