Ion Filtration Research Articles

Bio-Based PLA Membranes for Ion Transport and Ion Filtration

Lithium-ion batteries require battery separators for both safety and electrochemical performance. Due to that, they have received a lot of attention. In order to prevent any electronic current from moving within the negative and positive electrodes and allow ions to flow through while avoidance of electric contact between them, a porous membrane used as a separator is positioned between the electrodes with opposing polarities. Accordingly, the objective of the present work is to build a biodegradable PLA based battery separator, which has exceptional thermal capabilities and can endure temperatures of up to 300°C. They also seem to serve as the least degree of barrier for the flow of an ionic current. In this study bio-polymer battery separator membranes were developed using PLA as matrix material and fillers such as Copper slag (CS) and Cardanol resin (CNSL). CS and CNSL were preferred for the reason to realize the concept of a wealth reclaimed from wastes that act as toughening and pore forming agent for PLA matrix. It is found that at PLA-CS film has more brittleness when compared to neat PLA and PLA-CNSL resin. On the other hand, PLA-CNSL films are the toughest ones. Overall, it has been demonstrated that obtaining more sustainable and high-performance is possible by the usage of such sustainable materials for futuristic developments.

Graphene Oxide Membranes for Ionic/Molecular Filtration: From Self-Assembly to Design

The graphene oxide (GO) membrane holds great promise in desalination and green energy fields due to its naturally occurring nanochannels, which provide significant advantages in gas and ion filtration. In this study, the sizes and distributions of nanopore/channels in GO membranes and the relationship of GO flakes size and membrane thickness are explored by molecular dynamics simulations. Our results demonstrate that the size of GO flakes influences the distribution of nanopore sizes in GO membranes, while it almost has no influence on the total nanopore area in membranes with the same thickness. Additionally, our findings confirm that the total nanopore area of the GO membranes decreases exponentially as the membrane thickness increases, which is consistent with experimental observations. To expand the range of nanopore size regulation, we developed a columnar-array substrate model to create GO membranes customized for specific filtration functions, such as virus filtration. Our findings provide physical insights into the rational design of functional membranes for energy and environmental applications and offer theoretical guidance and technical support for the practical application of GO membranes in separation and filtration.

A mass defect filtering combined background subtraction strategy for rapid screening and identification of metabolites in rat plasma after oral administration of Yindan Xinnaotong soft capsule

The absorbed prototypes and metabolites of traditional Chinese medicines (TCMs) serves an important part in pharmacological action and clinical effects. However, the comprehensive characterization of which is facing actual or possible rigorous challenges due to the lack of data mining methods and the complexity of metabolite samples. Yindan Xinnaotong soft capsule (YDXNT), a typical traditional Chinese medicine prescription consisting of extracts from 8 herbal medicines, is widely used for the treatment of angina pectoris and ischemic stroke in the clinic. This study established a systematic data mining strategy based on ultra-high performance liquid chromatography tandem quadrupole-time-of-fight mass spectrometry (UHPLC-Q-TOF MS) for comprehensive metabolite profiling of YDXNT in rat plasma after oral administration. The multi-level feature ion filtration strategy was primarily conducted through the full scan MS data of plasma samples. All potential metabolites were rapidly fileted out from the endogenous background interference based on the background subtract and the chemical type specifically mass defect filter (MDF) windows including flavonoids, ginkgolides, phenolic acids, saponins, and tanshinones. As the MDF windows of certain types were overlapped, the screened-out potential metabolites were deeply characterized and identified according to their retention times (RT), integrating neutral loss filtering (NLF), diagnostic fragment ions filtering (DFIF), and further confirmed by reference standards. Thus, a total of 122 compounds, consisting of 29 prototype components (16 confirmed with reference standards) and 93 metabolites had been identified. This study provides a rapid and robust metabolite profiling method for researching complicated traditional Chinese medicine prescriptions.

Development of image similarity strategy based on targeted filtration for non-targeted HS-SPME/GC × GC fingerprints of volatile oils from Chinese patent medicines: A case of Chaihu Shugan Wan

To evaluate Chinese patent medicines more comprehensively, image similarity strategy based on targeted filtration was developed for non-targeted two-dimensional (2D) chromatographic fingerprints of volatile oil fraction in this paper. At first, volatiles and semi-volatiles were enriched from Chaihu Shugan Wan (CSW) by head space- solid phase micro-extraction (HS-SPME), and analyzed by comprehensive two-dimensional gas chromatography (HS-SPME-GC × GC). In succession, the inter-group and intra-group differences were distinguished by multi-component spectral correlative chromatography (MSCC). Facing the challenge of data complexity, some 50 contours were selected to indicate various medicinal materials through zone- specific ion filtration in 2D fingerprints. Among them, the known compounds were proven to be effective in “soothing liver-qi stagnation” through PubChem and other bioinformatic tools. Thirdly, Speeded Up Robust Features- Fast Library for Approximate Nearest Neighbors (SURF-FLANN) algorithm was utilized to estimate the pairwise similarities for the simplified fingerprints. In this procedure, the methodological examination was further made through the simulated images, including comparison with other algorithms, consideration for image complexity, and calculation of positives / negatives. At last, the similarities of six sample fingerprints were scored successfully. In summary, image similarity strategy based on zone- specific ion filtration can provide a viable solution for rapidly evaluating 2D fingerprints of extract fractions from Chinese patent medicines.

PRODUCTION OF CELLULOSE ACETATE MEMBRANE FROM COCOA (THEOBROMA CACAO L) SHELL MODIFIED POLYETHYLENE GLICOL FOR PB METAL ION FILTRATION

In this study, a modified polyethylene glycol modified cellulose acetate membrane was made. Cellulose acetate was synthesized from cocoa husk waste (Theobroma cacao L) with several steps, namely isolation of alpha cellulose from cocoa husk waste, synthesis of cellulose acetate from alpha cellulose, preparation of 10% cellulose acetate membrane with the addition of polyethylene glycol 0, 5, 10, 15, 20 & 25% . From the results of the research, it was found that the FT-IR analysis of -cellulose from cocoa shells showed an absorption peak at wave numbers between 3400 – 3500 cm-1 which indicated the presence of O-H stretch groups. At wave numbers 2800-2900 cm-1 indicates C-H stretching, then it can be seen at wave numbers 1160 cm-1 indicates C-O-C stretching, and at 1035-1060 cm-1 indicates C-O stretching. In the fingerprint area, we found absorption peaks at wave numbers around 1300 cm-1 which indicated the presence of C-H bending and around 1400 cm-1 indicating the presence of CH2 bending. The cellulose acetate obtained is white and smooth compared to alpha cellulose. At the membrane preparation stage, the results of the insoluble cellulose acetate & PEG using acetone as a solvent. So it is necessary to do a solubility test and find a suitable solvent to form polyethylene glycol modified cellulose acetate membrane for Pb metal ion filtration.

Chlorine geochemistry of various geothermal waters in China: Implications for geothermal system geneses

Understanding the geneses of geothermal systems is critical for their efficient and sustainable exploitation. Chlorine is one of the most conservative elements in geothermal waters and capable of providing valuable information related to the formation and evolution of geothermal systems, thereby being a promising indicator for identifying geothermal system geneses. In this study, representative hydrothermal systems located in various tectonic regions in China, including Daggyai, Semi, and Gudui in plate margin as well as Xinzhou and Xiong’an in inland Basins, were selected for investigating the chloride sources of the geothermal waters and possible mechanisms of chlorine isotope fractionation occurring in the relevant geochemical processes. The chloride of geothermal waters in Tibet originated predominantly from magmatic fluids input, whereas water–rock interaction was the primary chloride source for the Xinzhou geothermal waters. As for the chloride in Xiong’an, it was primary derived from the dissolution of halite in carbonate rocks. In addition, the major processes resulting in the chlorine isotope fractionation were supposed to be magma degassing in the Tibetan geothermal systems and ion filtration in the Xiong’an geothermal system. Based on the discovered chloride sources and possible processes inducing non-negligible chlorine isotope fractionation, the geneses of various geothermal systems investigated in this study were proposed. This study suggests that stable chlorine isotopes, coupled with other geochemical parameters, have the potential for discriminating geothermal systems with different geneses.

Analysis of chemical constituents of Sabia parviflora by ultrahigh performance liquid chromatography quadrupole time of flight tandem mass spectrometry

Effective and targeted identification of chemical components of the Chinese herbal medicine Sabia parviflora remains a major challenge. Herein, we used ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry to analyze the chemical composition of S.parviflora. Its chemical components were rapidly identified using the characteristic ion filtration method, which involves these steps: (1) summarize the characteristic ions based on similar skeletons and compounds with substitution patterns, and establish a database; (2) screen and classify different types of compounds in S. parviflora based on the characteristic ions; and (3) identify the compounds based on molecular weight, secondary fragments, and the database. In the present study, the characteristic ions in S. parviflora were grouped into five major classes. A total of 104 components were identified, including 12 potentially novel compounds. This rapid and accurate method provides an important basis for basic chemical research in S. parviflora.

Preparation of ZrO2/TiO2/Al2O3 Nanofiltration Lab-Scale Membrane for Filtering Heavy Metal Ions

ZrO2 is an excellent ceramic preparation material that can maintain chemical stability in medium–strong acid and alkali environments. The sintering impregnation method was used to prepare the ZrO2/TiO2/Al2O3 composite nanofiltration membrane (ZTA membrane). Nano-ZrO2, submicron TiO2, and microporous Al2O3 were used as the surface layer, the transition layer, and the support layer, respectively. The structure and phase of the membrane were measured by scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The composite membrane’s retention, hydrophilic and hydrophobic properties were characterized and evaluated using a UV–Vis spectrophotometer, a water contact angle tester (WCA), and a dead-end filtration device. With the increase in separation layer deposition time, the retention rate of methyl blue increased, and the water flux decreased. At a deposition time of 75 min, the retention rate of methyl blue was more than 80%, and the water flux reached 337.5 L·m−2 h−1 bar−1 at −1 bar transmembrane pressure. The membranes are hydrophilic and have different interception abilities for metal ions, and the order of retention effect is Ag+ > Cu2+ > Mg2+ > Na+, and Ag+ and Cu2+ reached 65.3% and 50.5%, respectively. The prepared ZTA composite nanofiltration membrane has potential application value in heavy metal ion filtration.

Lamellar water induced quantized interlayer spacing of nanochannels walls

The nanoscale confinement is of great important for the industrial applications of molecular sieve, desalination, and also essential in biological transport systems. Massive efforts have been devoted to the influence of restricted spaces on the properties of confined fluids. However, the situation of channel-wall is crucial but attracts less attention and remains unknown. To fundamentally understand the mechanism of channel-walls in nanoconfinement, we investigated the interaction between the counter-force of the liquid and interlamellar spacing of nanochannel walls by considering the effect of both spatial confinement and surface wettability. The results reveal that the nanochannel stables at only a few discrete spacing states when its confinement is within 1.4 nm. The quantized interlayer spacing is attributed to water molecules becoming laminated structures, and the stable states are corresponding to the monolayer, bilayer and trilayer water configurations, respectively. The results can potentially help to understand the characterized interlayers spacing of graphene oxide membrane in water. Our findings are hold great promise in design of ion filtration membrane and artificial water/ion channels.

A high-performance hydroxide exchange membrane enabled by Cu2+-crosslinked chitosan.

Ion exchange membranes are widely used to selectively transport ions in various electrochemical devices. Hydroxide exchange membranes (HEMs) are promising to couple with lower cost platinum-free electrocatalysts used in alkaline conditions, but are not stable enough in strong alkaline solutions. Herein, we present a Cu2+-crosslinked chitosan (chitosan-Cu) material as a stable and high-performance HEM. The Cu2+ ions are coordinated with the amino and hydroxyl groups of chitosan to crosslink the chitosan chains, forming hexagonal nanochannels (~1 nm in diameter) that can accommodate water diffusion and facilitate fast ion transport, with a high hydroxide conductivity of 67 mS cm-1 at room temperature. The Cu2+ coordination also enhances the mechanical strength of the membrane, reduces its permeability and, most importantly, improves its stability in alkaline solution (only 5% conductivity loss at 80 °C after 1,000 h). These advantages make chitosan-Cu an outstanding HEM, which we demonstrate in a direct methanol fuel cell that exhibits a high power density of 305 mW cm-2. The design principle of the chitosan-Cu HEM, in which ion transport channels are generated in the polymer through metal-crosslinking of polar functional groups, could inspire the synthesis of many ion exchange membranes for ion transport, ion sieving, ion filtration and more.

The Selective Transport of Ions in Charged Nanopore with Combined Multi-Physics Fields.

The selective transport of ions in nanopores attracts broad interest due to their potential applications in chemical separation, ion filtration, seawater desalination, and energy conversion. The ion selectivity based on the ion dehydration and steric hindrance is still limited by the very similar diameter between different hydrated ions. The selectivity can only separate specific ion species, lacking a general separation effect. Herein, we report the highly ionic selective transport in charged nanopore through the combination of hydraulic pressure and electric field. Based on the coupled Poisson–Nernst–Planck (PNP) and Navier–Stokes (NS) equations, the calculation results suggest that the coupling of hydraulic pressure and electric field can significantly enhance the ion selectivity compared to the results under the single driven force of hydraulic pressure or electric field. Different from the material-property-based ion selective transport, this method endows the general separation effect between different kinds of ions. Through the appropriate combination of hydraulic pressure and electric field, an extremely high selectivity ratio can be achieved. Further in-depth analysis reveals the influence of nanopore diameter, surface charge density and ionic strength on the selectivity ratio. These findings provide a potential route for high-performance ionic selective transport and separation in nanofluidic systems.

An Entire Process Optimization Strategy for Comprehensive In Vivo Metabolite Profiling of Prucalopride in Rats Based on Ultra-Performance Liquid Chromatography With Q-Exactive Hybrid Quadrupole-Orbitrap High-Resolution Mass Spectrometry.

Prucalopride was widely used for chronic constipation, which is difficult to be adequately relieved by laxatives in adult patients in clinic. Due to the difficulty in metabolite identification, metabolic process of prucalopride had not been investigated in vivo. In this study, an efficient strategy was proposed for comprehensive metabolite profiling of prucalopride after oral administration in rat plasma, urine, and feces samples. This strategy was composed of five steps. First, the samples at multiple time points after oral administration were collected to increase the representativeness of the samples. Second, different sample preparation methods were investigated to obtain superior extraction efficiency. Third, the raw data of test sample and blank sample were acquired using ultra-performance liquid chromatography with Q-Exactive hybrid quadrupole–orbitrap high-resolution accurate mass spectrometry under the positive and negative full-scan/dd MS2 mode. Fourth, combined mass defect filter with background subtraction model in soft of compound discovery, all peaks were constructed to filter potential metabolites after retention time alignment and ion filtration, which could remove large amounts of interference ions. Besides, it can predict potential biotransformation, promoting to understand how to metabolize the drug. This provides multiple possibilities and prevents us conjecturing the potential metabolites blindly. Finally, the verification procedure was implemented through exporting the structure and MS2 spectrum to the analytical tool of Mass Frontier. The proposed strategy significantly improved the targeted detection and identification for metabolites in vivo. A total of 47 metabolites were tentatively characterized in the plasma, urine, and feces samples after oral administration of prucalopride. This study could provide a valuable reference for systematic metabolite profile of drug in vivo.

Chlorine isotope data of chlorides challenge the pore fluid paradigm

In order to examine the seawater-seafloor sediment interactions that influence the chemical composition of seawater through time, we examined hundreds of pore fluid geochemical analyses from 13 clay-rich sedimentary successions drilled by the ODP-IODP. Chemical trends such as monotonous increases in Ca2+, and decreases in Mg2+ and δ18O with depth are traditionally interpreted to result from water-rock interaction. In this view, the release of Ca2+ into fluids and the uptake of Mg2+ and 18O mainly results from the formation of low-temperature clays in the sediment and within underlying basalts. Chloride concentration profiles and isotopic compositions, however, suggest that different processes may influence pore water geochemistry. The data examined here show relatively constant chloride contents but with a systematic decrease in δ37Cl of chlorides with depth from 0 permil (the seawater value) down to −8.5 permil. The δ37Cl data are highly correlated with δ18O (with δ18O down to −5.7 permil).The δ37Cl-depletions of pore fluid chlorides are found in all studied sedimentary piles regardless of tectonic or sedimentary history. These trends cannot be explained by water–rock exchange reactions because minerals formed at low temperature have Cl contents that are too low to compensate for δ37Cl depletions observed in pore fluids. Accordingly, we hypothesize that fluid-specific processes are responsible for the δ37Cl-depletions of the fluids and that δ37Cl-enriched chlorides were expelled out of the sediments into the ocean. After reviewing the fluid-specific processes that are known to change the chlorine isotope ratios in chlorides, we rule out diffusion and gravitational isotope fractionations of chlorides could generate this isotope pattern. The flow of a δ37Cl -depleted fluid from the underlying basaltic basement into the sediments could explain the δ37Cl data. But the mechanism that produces depletion in δ37Cl of the fluid remains unknown. It cannot be chloride exchanges between fluids and rocks.Here we show that compaction-induced ion filtration of chlorides through clay-rich membranes can produce the observed pore fluid δ37Cl-depletions, with isotope fractionation factors ranging from 1.000 to 1.008 between the chlorides of the expelled fluid (the permeate) and those of the residual fluid (the retentate). We find that smectite-rich sediments are associated with higher isotopic fractionation factors, while illite/chlorite-rich sediments are associated with intermediate values and with clay-poor sediments associated with lower values. This suggests that chlorine isotope fractionation might be controlled by surface charge associated with specific clay minerals. Our calculations show that compaction-induced filtration has the capacity to produce 18O-depletion for oxygen isotope fractionation factors between the expelled fluid and the retentate ranging from 1.000 to 1.005. 18O-enrichment in the expelled fluid is in agreement with the experimental data of Haydon and Graf (1986). Overall, although further experimental work on both chlorine and oxygen isotopes is certainly needed, the results of this study indicate that ion-filtration should be considered as a potential mechanism for fractionating isotopic species in sediment pore waters, particularly for oxygen isotope ratios whose variations are often commonly attributed to water–rock exchange.

Screening of lipid metabolism biomarkers in patients with coronary heart disease via ultra-performance liquid chromatography–high resolution mass spectrometry

Coronary heart disease (CHD) has a high mortality worldwide. This study aimed to screen lipid metabolism biomarkers in patients with coronary heart disease via ultra-performance liquid chromatography–high resolution mass spectrometry. Extraction and reconstitution solvents, liquid chromatographic and mass spectrometry conditions were optimized to detect more plasma lipid metabolites. In this study, the chromatographic and mass spectra characteristics of lipid metabolites were summarized. A total of 316 lipid metabolites were annotated via diagnostic fragment ion filtration, nitrogen rule filtration, and neutral loss filtration. Glycerophospholipid metabolism and sphingolipid metabolism were revealed as the main lipid disorders of CHD. This study provides a novel insight for high-throughput detection of lipid metabolites in plasma and provides a further understanding of the occurrence of CHD, which can provide valuable suggestions for the prevention of CHD.

Effect of Carbonation on the Leachability of Solidified/Stabilized Lead‐Contaminated Expansive Soil

Lime, fly ash, and alkaline residue are used widely as effective binders to solidify/stabilize heavy metal‐contaminated expansive soil. Carbonation, however, may influence the effectiveness of solidification/stabilization (S/S) by decomposing hydration products and decreasing pH, which would seriously damage the long‐term durability of stabilized soils. This study focused on the variation of leaching characteristics of solidified/stabilized lead‐contaminated expansive soils before and after accelerated carbonation under the leachant of pH 3 and 5 by the semidynamic leaching test. After semidynamic leaching, leaching indexes such as the effective diffusion coefficient (De), leachability index (Lx), and slope (rc) were used to reveal the ion leaching mechanism. The results indicated that the amount of Pb2+ and Ca2+ leached out under different pH conditions increased after carbonation, which confirmed that carbonate on solidified/stabilized lead (Pb) had a negative impact. Additionally, the De values of Pb2+ and Ca2+ varied in the range of 1.16E − 10 cm2/s to 1.71E − 07 cm2/s, which demonstrated that ion migration was low. The contaminated soil solidified by lime and AR could be used in “controlled utilization” as Lx was higher than 9, and the leaching process was controlled by a dissolution reaction according to the analysis of rc. Moreover, the strong acidic leachant (pH = 3) resulted in more ions leaching out and lower pH in leachate compared with a mildly acidic leachant. Finally, with literature and experimental results, we found that the main reason for the increase of lead ion filtration of the carbonation reduced the pH value of the matrix and made the hydration products denatured and decomposed.

Electrolyte formulation to enable ultra-stable aqueous Zn-organic batteries

Aqueous zinc batteries (ZBs) possess great potential in energy storage due to their advantages in safety, low-cost and resource abundance. However, the commercialization of ZBs is plagued by the lacking of suitable cathode structures (or nano-textures) and their poor cycle life. The popular cathode materials of Mn or V based oxides suffer from the high solubility and toxicity of transition metals (TMs). It is highly required to develop robust TM-free organic cathodes with design flexibility and environmental benignity. Herein, 1,4,5,8-naphthalene diimide (NDI) layered molecules are proposed as cathode candidate for ZBs, and they are characterized by sufficient interconnection of nano-particles (for continuous electron transport) into porous network (for facilitated ion filtration). It enables the achievement of reversible redox of carbonyl function groups and a stable gravimetric capacity around 200 mAh g−1. The superior cycling and rate performance (at least 5000 cycles under 3 A g−1) benefits from the electrolyte formulation. The blending of Na2SO4 additive takes effect in terms of the cathode grain attenuation into ultrathin 2D nanosheets, pseudo-capacitance contribution enhancement and Zn anode smoothening.

Sunlight-assisted tailoring of surface nanostructures on single-layer graphene nanosheets for highly efficient cation capture and high-flux desalination

Highly efficient approaches using nanomaterials for ion capture and desalination have been widely explored to address fresh water scarcity worldwide; however, the complex preparation process and the large-scale and high-density perforation of porous graphene layers remain technical challenges. Herein, we found that sunlight-assisted tailoring of surface nanostructures involving controllable morphological and structural alterations of graphene unequivocally improved the ion adsorption and ion filtration performance. Notably, the interlayer spacing of single-layer graphene could be sufficiently tuned via lighting control to promote selective interactions between ions and nanosheets. After 7 d simulated sunlight treatment, the transformed SLG (SLG-S7) exhibited 86.1%, 77.3% and 46.1% increases of adsorption capacity for Na+, Pb2+ and Fe3+ in the complex ion system, respectively. Notably, the adsorption capacity of SLG-S7 for single Pb2+ was even 2.3-fold greater than that of pristine SLG. Further, the layer-stacked SLG-S7 membrane achieved super water fluxes (167.1 L m−2 h−1 bar−1) and a high separation performance without sacrificing salt ion rejection, which was attributed to the sunlight-induced larger water transport channels and defect-free nanosheets in the membrane. This work provides new insight for the design of novel graphene-based nanostructures to address the increasingly serious water contamination issue and the scarcity of fresh water.

Quantitation of Cyclosporin A in Cell Culture Media by Differential Mobility Mass Spectrometry (DMS-MS/MS).

Cell permeability is an important factor in determining the bioavailability of therapeutics that is usually measured by cell culture testing. The concentration of pharmaceutical in a medium such as Hank's Balanced Salt Solution with HEPES organic buffer (HBSS-HEPES) is measured at a series of time points, making simplicity and high throughput of the analytical method important characteristics. We report an electrospray differential mobility spectrometry mass spectrometry method (nanoESI-DMS-MS) for the rapid determination of cyclosporin A (CsA, cyclosporine) concentration in such a buffer. DMS technology provides gas phase atmospheric pressure ion filtration for small-molecule bioanalytical methods that suppresses interfering ions and reduces chemical noise, without the use of chromatography. This allows simplified sample preparation, fast calibration curve development, and shortened analysis times. It has also been noted that the DMS prefilter can reduce contamination of the mass spectrometer by salts, thereby extending mass spectrometer system uptime.In the application described here, DMS-MS/MS is applied to cyclosporine A (CsA) in cell medium. Sample preparation is limited to dilution with an ammonium acetate-methanol-water mobile phase and the addition of CsA-d4 internal standard. The isotope ratio data are obtained in DMS-MS MRM mode observing NH3 loss from the ammonium adduct of the two species. A calibration curve with high linearity (R2=0.998) is rapidly obtained with nearly zero intercept, while it was found that a liquid chromatography LC-MS method required a preliminary SPE step to obtain a linear calibration curve. The time for data acquisition in the DMS-MS MRM method with flow injection (FIA) or infusion introduction at ESI flow of 400nL/min is typically 30s leading to a cycle time of less than 1min.

Strategy for rapid screening of antioxidant and anti-inflammatory active ingredients in Gynura procumbens (Lour.) Merr. based on UHPLC-Q-TOF-MS/MS and characteristic ion filtration.

Gynura procumbens (Lour.) Merr. is traditionally used as a raw material for making dumplings or steamed stuffed buns, and its fresh leaves are boiled with water for tea. Herein, we established an ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) combined with characteristic ion filtration (CIF) strategy to rapidly screen active ingredients with antioxidant and anti-inflammatory properties in G. procumbens. This strategy involved screening the active part of G. procumbens using antioxidation and anti-inflammatory activity assays; discovering the active compounds by speculating on the active site's chemical composition by UHPLC-Q-TOF-MS/MS plus CIF; and verifying the active compounds' activities. The ethyl acetate extract (EEAF) of G. procumbens was the major active site. Eighty-one compounds were identified from the EEAF using UHPLC-Q-TOF-MS/MS plus CIF. Furthermore, polyphenols such as cynarine, isochlorogenic acids A and isochlorogenic acids C have excellent antioxidizing and anti-inflammatory activities. This study provides a practical strategy for rapid in vitro screening of the antioxidizing and anti-inflammatory activities of traditional vegetables and herbs and identification of active ingredients.

Graphene stretches to fast ion filtration

Graphene stretches to fast ion filtration