Simple Separation Technique Research Articles

Development of low-molecular-weight polysaccharide-based wound dressings for full-thickness cutaneous wound healing via coacervate formation

The development of polysaccharide-based wound dressings that are easy to prepare, adhere to tissue, adapt to diverse shapes and exhibit tunable mechanical properties holds significant clinical interest. This study introduced a simple spontaneous liquid-liquid phase separation technique employing low-molecular-weight and high polyion concentration of chitosan (CS) and hyaluronic acid (HA) to fabricate CS/HA coacervates. Upon increasing the molecular weight of chitosan from 7 kDa to 250 kDa, a transition in the CS/HA coacervates from liquid-like state to an elastic liquid and eventually to a solid-like state was observed. The resulting CS/HA coacervates demonstrated robust water resistance and adhesion to skin tissue. Notably, the molecular weight of chitosan significantly influenced the mechanical properties and hydration levels of the CS/HA coacervates. Moreover, in vivo studies using a full-thickness cutaneous defect model revealed that the CS/HA coacervates, prepared using 100 kDa chitosan, markedly accelerate wound healing. The coacervates' ease of preparation, wet adhesion, heterogeneous structure, suitability for irregularly shaped wounds, and exceptional wound healing promotion of the coacervates qualify them as an optimal wound dressing.

High‐Efficiency Separation of Near‐Zigzag Single‐Chirality Carbon Nanotubes by Gel Chromatography

High‐efficiency production of near‐zigzag single‐chirality single‐wall carbon nanotubes (SWCNTs) is of great importance for their property study and applications. The key to separate near‐zigzag single‐chirality SWCNTs by gel chromatography is to selectively adsorb them in the gel medium. In this study, by using a high surfactant ratio of sodium dodecyl sulfate and sodium cholate (≥4:1) to modulate the selective adsorption of distinct (n, m) SWCNTs in a gel column, a high enrichment of near‐zigzag SWCNTs adsorbed in the gel column is achieved, which usually have a low abundance in raw materials due to their low growth efficiency. Afterward, (7, 3), (8, 3), (8, 4), (9, 1), and (9, 2) single‐chirality SWCNTs are separated with small chiral angles less than 17° by following a stepwise elution for their selective desorption. This simple and efficient separation technique will promote the research and application of near‐zigzag SWCNTs.

Sample-to-answer lateral flow assay with integrated plasma separation and NT-proBNP detection

Through enabling whole blood detection in point-of-care testing (POCT), sedimentation-based plasma separation promises to enhance the functionality and extend the application range of lateral flow assays (LFAs). To streamline the entire process from the introduction of the blood sample to the generation of quantitative immune-fluorescence results, we combined a simple plasma separation technique, an immunoreaction, and a micropump-driven external suction control system in a polymer channel-based LFA. Our primary objective was to eliminate the reliance on sample-absorbing separation membranes, the use of active separation forces commonly found in POCT, and ultimately allowing finger prick testing. Combining the principle of agglutination of red blood cells with an on-device sedimentation-based separation, our device allows for the efficient and fast separation of plasma from a 25-µL blood volume within a mere 10 min and overcomes limitations such as clogging, analyte adsorption, and blood pre-dilution. To simplify this process, we stored the agglutination agent in a dried state on the test and incorporated a filter trench to initiate sedimentation-based separation. The separated plasma was then moved to the integrated mixing area, initiating the immunoreaction by rehydration of probe-specific fluorophore-conjugated antibodies. The biotinylated immune complex was subsequently trapped in the streptavidin-rich detection zone and quantitatively analyzed using a fluorescence microscope. Normalized to the centrifugation-based separation, our device demonstrated high separation efficiency of 96% and a yield of 7.23 µL (= 72%). Furthermore, we elaborate on its user-friendly nature and demonstrate its proof-of-concept through an all-dried ready-to-go NT-proBNP lateral flow immunoassay with clinical blood samples.Graphical

Treatment of surfactant wastewater by foam separation: Combining the RSM method and WOA-BP neural network to explore optimal process conditions

In the field of water treatment, the treatment of wastewater containing surfactants has been an important issue. The foam separation technique is often used to separate surfactants from water as a simple and efficient separation technique. We used a newly designed foam separation column to treat wastewater containing sodium dodecyl sulfonate (SDS) (0.5–2.0 mmol/L). The effects of initial SDS concentration (CSDS, i), operation time (t), foam height (H), gas velocity (V) and pH value (1−7) on the separation effect of SDS were investigated. The Box-Behnken design model was used to design the experimental group, and the process parameters of foam separation were optimized by combining response surface methodology (RSM) and WOA-BP neural network. The results showed that the prediction accuracy of the optimized BP neural network using the WOA algorithm was superior to that of the RSM model. The best operating parameters were: CSDS,i (0.88 mmol/L), t (28.13 min), H( 81.3 cm), V (1.03 L/min) and pH (3.5) and the recovery rate of SDS was up to 97.32%.

Application of foam separation in production of β-glucanase in Pichia

Abstract β-glucanase is widely used in many fields and has great economic value and development space, but it faces the difficulties of separation and nutrient destruction in the process of industrial production. Foam separation is a simple, mild and efficient adsorption separation technique that enables efficient separation and extraction of β-glucanase. In this study, five single factors (loading volume, pH, separation gas velocity, fermentation loading concentration, surfactant concentration) of foam separation and harvest of β-glucanase produced by Pichia pastoris were studied. The best univariate condition was: 600 mL/min separation gas velocity, loading volume of 200 mL, initial enzyme concentration of 100 g/mL, surfactant concentration of 0.3 mg/mL and pH of 5. Based on the best univariate condition, the optimal separation conditions of β-glucanase were further explored, and the five-factor four-level orthogonal test was designed. From the experimental results, the best separation condition was: 600 mL/min, loading volume of 200 mL, initial enzyme concentration of 100 μg/mL, surfactant concentration of 0.5 mg/mL and pH of 5. Under this separation condition, the enrichment ratio (E) was 0.56 and the recovery rate (R) was 96.01%.

Magnetic nanomaterials: Greener and sustainable alternatives for the adsorption of hazardous environmental contaminants

The global water resources have been considerably damaged by organic and inorganic pollutants generated as a result of fast urbanization and industrialization. Toxic contaminants in water pose a serious health threat to both humans and aquatic life. In terms of cost and performance, current remediation technologies are inadequate for eliminating low-concentration contaminants. Nanomaterials have unique advantages in this regard, including precisely adjustable surface areas, durability, and biocompatibility. Also, the surface functionalization of the nanoparticles can facilely be carried out to increase their selectivity and specificity towards a variety of pollutants. Among various nanomaterials the magnetic nanoparticles (MNPs) are promising class of nanomaterials due to their biocompatible, target-specific, easily regenerable, and reusable characters. They also feature simple separation techniques, high surface-to-volume ratios, and high adsorption rates. Based on these features their implication in wastewater treatment has dragged an enhanced amount of attention for the researchers. Therefore, MNPs provide a simple, low-maintenance alternative to traditional adsorbents for extracting contaminants from wastewater. Magnetic separation can reduce the environmental impact of MNPs in final effluents by managing the concentration of nanoadsorbents. MNPs are now in the development stage, however they are a promising treatment alternative for large-scale water treatment plants. The main objective of the present review is to focus on the efforts being carried out in the application of MNPs for the remediation of hazardous pollutants including organics, heavy metal ions, pharmaceutics, dyes, radioactive elements, and pathogens. Furthermore, the review present critical assessment and overview of a variety of magnetic nanomaterials and their applications to water and wastewater treatment. Finally, the feasibility of structure-property relationships, adsorption mechanisms, modeling for the removal of water pollutants, legality and toxicity, economic assessments, and future research directions for the complete utilization of MNPs are also discussed in detail.

Differential quadrature solution for composite flat plates with delamination using higher-order layerwise models

This paper deals with the numerical modeling of delaminated composite plates by applying the differential quadrature method. A semi-layerwise modeling technique developed by the author including the first-, second- and third-order shear deformation plate theories is utilized. The proposed model captures separately the delaminated and the intact parts of the plates with straight delamination front. Firstly, the governing differential equations are presented and then it is shown how these were discretized by using a recommended grid structure and the required boundary and continuity conditions. Some plate problems with simply supported and rigidly fixed edges are solved including some variations of the size and the thicknesswise position of the material defect. One of the non-trivial aspects of the differential quadrature solution is how the continuity between the different regions can be imposed. It will be shown that at the mutual grid points of the neighboring regions it is not possible to satisfy each continuity condition against the stress resultants, and thus although some conditions are violated, the problems can be solved accurately by properly choosing the actual conditions. Once, the differential quadrature solution became available the mechanical fields were determined, too. Moreover, the J-integral can be determined and together with a simple mode separation technique even the mode-II and mode-III components became available. The comparison of results to those by spatial finite element models shows very good accuracy and the effectiveness of the proposed differential quadrature solution.

Removal of Dye from Synthetic Wastewater by Liquid Membrane

New technologies have risen into popularity causing the Liquid membrane techniques to evolve over other separation techniques due to its high selectivity and recovery, increased fluxes, and reduced investment and operating cost. This work focuses on extracting Methylene Blue (MB), a cationic dye using a simple BLM separation technique from its aqueous phase. It combines extraction and stripping in a single unit operation. The feed phase was an aqueous solution of MB, the solvent chosen was soybean oil for the liquid/organic membrane phase, and tri-octyl amine acted as a carrier. The strip phase was a hydrochloric acid solution for this study. A two-phase equilibrium study was done to choose the correct solvent, carrier, and receiving phase (soybean oil, tri-octyl amine, and HCl) were chosen, which was then followed by a three-phase study. Effect of various parameters like equilibrium time, feed and stripping phase pH, stirring speed, carrier concentration, initial feed concentration, and strip phase concentration were all studied to find out the most optimum working condition for maximum extraction and recovery of MB. The removal efficiency of MB by using soybean oil was found as 92%, at the optimum process conditions for the transport of MB were found as follows: pH in the feed phase (11), pH in the stripping phase (5), initial concentration of MB (20 ppm), carrier concentration (7%) (v/v) TOA and stirring speed (250 rpm), respectively.

GREENER SYNTHESIS OF PYRANOPYRAZOLE DERIVATIVES CATALYZED BY CaO NANOPARTICLES

We report on the development of a novel green synthetic protocol for the series of pyrano-pyrazole derivatives (5an) in a one-pot multi-component method using CaO nanoparticles as the heterogeneous catalyst. The CaO nanoparticles were synthesized by a greener route using an economic and efficient alternative i.e. papaya leaf extract and exhibited excellent catalytic activity, and this plant-mediated synthesis of CaO nanoparticles is a very promising area of research. CaO nanoparticles can be efficiently used in the synthesis of pyrano-pyrazoles and this catalytic approach can deliver the appropriate products in a rapid reaction time with a high yield (85–91%).The current protocol has various advantages, including a short reaction time, a high percent yield, a clean reaction, a simple separation technique, and a recoverable catalyst that retains its catalytic activity when utilized in subsequent reactions.Characterization of synthesized pyrano-pyrazole derivatives is done by IR, 1H and 13C NMR spectral data as well as HOMO-LUMO calculations.

Research progress in the application of external field separation technology and microfluidic technology in the separation of micro/nanoscales

微纳尺度物质的分离和分选在精准医学、材料科学和单细胞分析等研究中至关重要。精准、高效和快速的分离微纳尺度物质能够为癌症的早期诊断、生物样品检测和细胞筛选提供重要帮助,其中基于外加场分离技术的分离微纳尺度物质因可以对微纳尺度物质高效在线分离和分选,被广泛应用于微纳米颗粒、外泌体以及生物细胞的分离工作中,而目前多数外加场分离技术存在装备繁琐和样品消耗大等问题。微流控技术是一种通过制作微通道和微流控芯片操纵微小流体对微纳尺度样品组分进行分离的技术,因具有快速检测、高通量、在线分离、集成性高、成本低等优势现被应用于微纳尺度物质分离分析中,是一种微纳尺度物质分离的有效方法,通过在微流控芯片上设计不同的通道及外部配件提高主动场对微纳尺度物质分离效率。外加场分离技术与微流控技术联用可以实现微纳尺度物质的无损、高效、在线分离。该综述主要概述了近年来在微流控芯片上依托流动场、电场、磁场及声场等外加场分离技术来提高对微纳尺度物质分离效率的研究现状,并将各个外力场对单细胞、微颗粒等微纳尺度物质的分离进行分类介绍,总结各自的优缺点及发展应用,最后展望了外加场分离技术与微流控技术联用在应用于癌细胞的早期筛查、精确分离微尺度物质领域的未来发展前景,并提出联用技术的优势和未来应用等。

Tailoring the Random Lasing Properties by Controlled Phase Separation Process in PMMA:PVK Dye-Doped Polymeric Blends.

This article describes the random lasing (RL) phenomenon obtained in a dye-doped, polymeric double-phase system composed of PMMA and PVK polymers. It shows how relative concentrations between mentioned macromolecules can influence lasing parameters of the resulting blends, including obtained emission spectra and threshold conditions. We describe the influence of lasers’ composition on their morphologies and link them with particular RL properties. Our studies reveal that the disorder caused by phase separation can support the RL phenomenon both in the waveguiding and quasi-waveguiding regimes. Changing the relative concentration of polymers enables one to switch between both regimes, which significantly influences threshold conditions, spectral shift, number of lasing modes, and ability to support extended and/or localized modes. Finally, we show that a simple phase separation technique can be used to fabricate efficient materials for RL. Moreover, it enables the tailoring of lasing properties of materials in a relatively wide range at the stage of the laser material fabrication process in a simple way. Therefore, this technique can be seen as a fast, cheap, and easy to perform way of random lasers fabrication.

Selective Pd Separation from Simulated Radioactive Liquid Waste by Precipitation Using Xenon Lamp Irradiation for a Simplified Procedure.

In this study, we developed a simple and one-step Pd separation technique based on photoreduction with Xe lamp irradiation for the determination of 107Pd in highly radioactive samples. A simulated high-level radioactive liquid wastes (HLLW) solution, consisting of 14 major elements in a 3 mol L-1 HNO3 solution, was used to evaluate the separation performance. The Pd precipitate was formed by Xe lamp irradiation, and recovered by centrifugation. The Pd recovery from the simulated HLLW solution reached up to 50%, while 99.5% of the other 13 elements was separated. These results indicate that the applicability of the proposed separation technique to HLLW samples.

Preparation of 6-amino-6-deoxy cellulose and its derivatives used as chiral separation materials

In order to find a facile and practical method to synthesize amino cellulose in bulk with high regional selectivity and high degree of substitution, the reaction conditions to brominate cellulose and to reduce azido group were carefully studied and some interesting phenomena were observed. With the optimized method, 6-amino-6-deoxy cellulose could be easily prepared with very simple separation techniques. The degree of substitution of the amino group amounted to 0.97 which was determined by 1H NMR spectrum of 6-benzamido-6-deoxy cellulose. Moreover, the amino group was evidenced to be at the C6 of glucose unit by 1H-1H COSY NMR and 1H-13C HSQC NMR spectra. In addition, three cellulose 6-acetamido-6-deoxy-2,3-bis(phenylcarbamate)s were prepared from the 6-amino-6-deoxy cellulose prepared with the techniques optimized in the present study. The developed cellulose derivatives were used as chiral selectors with which chiral stationary phases (CSPs) were prepared. The CSPs exhibited enantioseparation power to some chiral compounds.

Separation and concentration of ω-3 PUFA-rich phospholipids by hydration of krill oil

Krill oil (KO) is unique in contrast to fish oil because the ω-3 PUFAs, particularly eicosapentaenoic (EPA) and docosahexaenoic (DHA), are almost exclusively esterified on phospholipids (PL) rather than triglycerides (TAG) which improves bioavailability and water solubility. Therefore, the primary aim of this study was to use the principles of water degumming to separate PL from TAG in KO. Water was mixed with KO in varying ratios, centrifuged for separation and freeze-dried. Separation into gum and oil fractions occurred in the 75:25 and 50:50 KO:H2O samples. TLC-densitometry revealed 67.6 ± 1.97% and 49.73 ± 3.90% PL concentrations (p < 0.05) in the lipid recovered from the 75:25 and 50:50 KO:H2O sample, respectively. The 75:25 KO:H2O gum fraction did not contain detectable triglycerides (TAG); however, the 50:50 KO:H2O gum fraction had 23.88 ± 6.36% (p < 0.05). The fatty acid profile of the 75:25 KO:H2O gum fractions presented with more EPA and DHA than the oil fraction (p < 0.05). Phosphatidylcholine (PC) with EPA and DHA fatty acids attached concurrently at sn-1 and sn-2 (i.e., PC-EPA/EPA, PC-EPA/DHA, and PC-DHA/DHA) and was present in the gum fractions of both samples. This approach offers a simple separation technique to separate health-beneficial PL from KO.

Graphitic carbon nitride nanosheets prepared by electrophoretic size fractionation as an anticancer agent against human bone carcinoma.

Graphitic carbon nitride, g-C3N4, is a fascinating candidate for biomedical applications. Of course, bulk g-C3N4 is not appropriate for this purpose due to its large size distribution and low dispersion in water. Herein, for the first time, the electrophoretic size fractionation of g-C3N4 without introducing some functional groups into its structure was performed within a very short time. This simple separation technique resulted in several factions. The smallest collected fraction was nanosheets and showed the enhanced photoluminescence properties such as high PL intensity and bright luminescence. The nanosheets demonstrated significantly higher toxicity (IC50 of 27.0±4.2μg/ml- after 48h) against human bone carcinoma cell line, Saos-2, in the absence of external light source compared to the bulk g-C3N4 (IC50 of 104.0±8.5μg/ml- after 48h) without any cytotoxic effect on normal cells, human foreskin fibroblast.

Employing high-temperature gas flux in a residual salt separation technique for pyroprocessing

Abstract Residual salt separation is an essential step in pyroprocessing because its reaction products, as prepared by electrochemical unit processes, contain frozen residual electrolyte species, which are generally composed of alkali-metal chloride salts (e.g., LiCl, KCl). In this study, a simple technique that utilizes high-temperature gas flux as a driving force to melt and push out the residual salt in the reaction products was developed. This technique is simple as it only requires the use of a heating gun in combination with a gas injection system. Consequently, LiNO3–ZrO2 and LiCl–ZrO2 mixtures were successfully separated by the high-temperature gas injection (separation efficiency > 93%), thereby demonstrating the viability of this simple technique for residual salt separation.

Fabrication of thin fluoropolymer adhered cotton fabric surface for efficiently microscopic to macroscopic level oil/water separation

We report a simple oil-water separation technique using adhesively attached fluoropolymer coated cotton fabric prepared by the admicellar polymerization process. The modified cotton fabric shows hydrophobic/oleophilic properties with a high water contact angle of 126° ± 1 and an oil contact angle of ∼0°. For the oil-water separation, we used two techniques i.e. filtration-based and absorption-based separation. The modified cotton fabric can effectively separate a series of oil-water mixtures like kerosene/water (Gasoline), petrol/water, hexane/water, octane/water and decane/water with high efficiency. Among them, kerosene–water mixture shows approx ∼93% separation efficiency even after repeated use for 10 cycles through an ordinary filtering process, without any noticeable change in efficiency. More importantly, the as-prepared fabric shows good recyclability after several separations. Therefore, this modified cotton fabric has the advantages of scalable fabrication, cost-effective preparation, low-energy consumption, high separation efficiency, and excellent recyclability.

High-resolution separation of DNA/proteins through nanorod sieving matrix

In this paper, we report on an integrated nanorod array as a novel sieving matrix for high-resolution separation of biomolecules. A wide size range of DNA (100 bp–166 kbp) and proteins (11.4 kDa–205 kDa) are resolved into sharp peaks within several minutes using devices with various pore apertures, either in a reptation mode or Ogston mechanism. The device delivers notable performance with the minimum resolvable size difference 10 bp for 100 bp and 150 bp DNA fragments, 15.9 kbp for 48 kbp and 166 kbp DNA chains, and 7.9 kDa for 11.4 and 68 kDa proteins, where the separation efficiency is higher than or comparable to other micro/nanofabricated artificial sieving structures. The process utilizes localized oblique angle deposition (LOAD) to simply integrate densely packed nanorods onto steep sidewalls of microfluidic channels, which eliminates the requirement of advanced lithography tools routinely used in conventional artificial sieving structures. We further demonstrate the modulation of pore aperture that employs the sculptured sidewalls by a custom deep reactive-ion etching (DRIE) recipe. Given the easy fabrication, excellent engineering control and outstanding sieving capability, this nanorod sieve device has great potentials to provide a simple and effective separation technique for biomolecule analysis.

New extraction technique of zirconium and hafnium from zircon mineral

Zirconium and hafnium compounds are widely used in today’s technology. Zirconium or hafnium carbides and borides are high temperature ceramics.The present study concerns primarily with optimizing the extraction of zirconium and hafnium from their naturally occurring mineral, zircon, via a wet chemical process. First , zircon heated with molten sodium hydroxide to form zironate and silicate frit. Simple separation technique of sodium silicate from the zirconate and hafnate sodium was then applied to obtain a silicate-free frit, then the extraction of the zirconium ( IV ) and hafnium ( IV ) basic sulfates from their oxychloride solution leaving almost all other ions soluble in the mother liquor was achieved by adjusting the pH value. The precipitate of zirconium ( IV ) and hafnium ( IV ) basic sulfates was dried, weighed, analyzed and percent of the zirconium and hafnium extracted were found to be 97 % of their original concentration.

Three-phase partitioning for the direct extraction and separation of bioactive exopolysaccharides from the cultured broth of Phellinus baumii

In this study, three-phase partitioning (TPP) was used to directly extract and separate bioactive exopolysaccharides (EPSs) from a cultured broth of Phellinus baumii. The maximum extraction yield of EPS was 52.09% under the following optimal conditions: 20% (w/v) ammonium sulfate concentration, 1.0:1.5 (v/v) ratio of cultured broth to t‑butanol, 30 min, and 35 °C. A multifrequency power ultrasound in a sequential mode coupled with TPP resulted in ~9.12% increment in extraction yield and ~80% reduction in extraction time compared with those of traditional TPP. The carbohydrate (88.21%) and uronic acid (3.37%) contents of partially purified EPS were higher than those of EPS-C obtained through conventional ethanol precipitation and separation methods. EPS and EPS-C exhibited similar preliminary structural characteristics and different monosaccharide compositions and molecular weights. The radical-scavenging abilities, antioxidant capacities, α‑amylase and α‑glycosidase inhibitory activities, and macrophage stimulation activities of EPS were also higher than those of EPS-C. Therefore, it could be concluded that TPP as a simple and green separation technique could be used to directly extract and separate bioactive EPS from the fermentation broths of mushrooms and other fungi.