Abundant Ions Research Articles

Aza-Prilezhaev Aziridination-Enabled Multidimensional Analysis of Isomeric Lipids via High-Resolution U-Shaped Mobility Analyzer-Mass Spectrometry.

Unsaturated lipids constitute a significant portion of the lipidome, serving as players of multifaceted functions involving cellular signaling, membrane structure, and bioenergetics. While derivatization-assisted liquid chromatography tandem mass spectrometry (LC-MS/MS) remains the gold standard technique in lipidome, it mainly faces challenges in efficiently labeling the carbon-carbon double bond (C═C) and differentiating isomeric lipids in full dimension. This presents a need for new orthogonal methodologies. Herein, a metal- and additive-free aza-Prilezhaev aziridination (APA)-enabled ion mobility mass spectrometric method is developed for probing multiple levels of unsaturated lipid isomerization with high sensitivity. Both unsaturated polar and nonpolar lipids can be efficiently labeled in the form of N-H aziridine without significant side reactions. The signal intensity can be increased by up to 3 orders of magnitude, achieving the nM detection limit. Abundant site-specific fragmentation ions indicate C═C location and sn-position in MS/MS spectra. Better yet, a stable monoaziridination product is dominant, simplifying the spectrum for lipids with multiple double bonds. Coupled with a U-shaped mobility analyzer, identification of geometric isomers and separation of different lipid classes can be achieved. Additionally, a unique pseudo MS3 mode with UMA-QTOF MS boosts the sensitivity for generating diagnostic fragments. Overall, the current method provides a comprehensive solution for deep-profiling lipidomics, which is valuable for lipid marker discovery in disease monitoring and diagnosis.

Cyclable CuⅠ-Ov-Mn sites accelerate O2 activation to enhance photo-driven catalytic oxidation performance

Molecular oxygen activation (MOA) plays a crucial function in various oxidation reactions. Nonetheless, facile, continuous and efficient MOA remains challenging. Herein, we have successfully constructed recyclable CuⅠ-Ov-Mn sites (Ov: oxygen vacancy) for MOA by incorporating Cu single atoms in MnO2 matrix. The localized photogenerated electron at CuⅡ site drives the generation of electron-rich CuⅠ species and an adjacent photoinduced Ov, which possesses stronger O2 affinity and affords a durable O2 activation site. The CuⅡ/CuⅠ cycle accelerates the separation of charge carriers to supply adequate photogenerated electrons and assures the renewability of photoinduced Ov, thus realizing rapid and sustained O2 activation and generating abundant monatomic oxygen ions (O-). Consequently, Cu-MnO2 catalyst performed extraordinarily high activity in O2-involved reactions. For instance, in toluene oxidation, toluene conversion reached as high as 96 %, comparable to that on the state-of-the-art supported Pt catalysts. This work will bring more possibilities for modulating the O2-involved oxidative reactions.

Nanocellulose membrane with double-salt deep eutectic solvent for efficient carbon capture

Membrane-based gas separation technology is becoming increasingly attractive as a feasible alternative for carbon capture to alleviate global warming. Here, a double-salt deep eutectic solvent (DES) composed of organic salt (choline chloride) and inorganic salt (ZnCl2) is designed. The as-prepared DES exhibits a superb affinity and compatibility with nanocellulose because of the interactions between salt ions and cellulose carboxyl/hydroxyl groups. Through a solvent impregnation process, the DES was integrated into the nanocellulose gel precursor and used as a facilitated transport agent to form the functionalized nanocellulose membrane. The DES is tightly attached to the cellulose fibers with a high uniformity in the membrane matrix. Gas separation tests demonstrated that the DES@nanocellulose membranes presented a maximum CO2 permeability of 155.8 Barrer, with CO2/N2 and CO2/CH4 ideal selectivities of 43.6 and 48.4, respectively. Mixed gas separation tests were performed and the optimal membrane exhibited separation factors of 48.1 and 52.3 for CO2/N2 and CO2/CH4, respectively. The membranes provide a high solubility for CO2 due to the presence of abundant zinc ions, choline cations and carboxyl groups in the network, which can establish reversible coordination with CO2 and promote CO2 transport.

Variations of Heavy Ions in Interplanetary Shock Driven by Interplanetary Coronal Mass Ejections and Stream Interaction Regions

In the solar wind, the fluctuation of heavy ion abundance serves as a crucial physical metric. This not only mirrors the attributes of the solar wind’s originating solar region but also signifies its influence on Earth’s magnetosphere. Utilizing data from the Advanced Composition Explorer satellite, this investigation scrutinizes heavy ion variations in stream interaction region (SIR)- and interplanetary coronal mass ejection (ICME)-driven shocks. We further delineate the disparities in heavy ion fluctuations between these two types of interplanetary shocks across diverse solar activity cycles. Our findings reveal that ICME-driven shocks typically manifest elevated shock velocities and magnetic field strengths relative to their SIR-driven counterparts. Additionally, heavy ion abundance ratios, such as C6+/O4+, O7+/O6+, He/O, Si/O, and Fe/O, are consistently higher in ICME-driven shocks than in SIR-driven shocks. During varying solar activity cycles, these ratios surge postarrival of ICME-driven shocks. At solar maximum, these elevated ratios persist, whereas they revert to baseline levels swiftly during solar minimum. For SIR-driven shocks, the alteration in heavy ion abundance ratios is comparatively subdued, yet a noteworthy correlation with the solar activity cycle is evident.

Adding Color to Mass Spectra of Biopolymers: Charge Determination Analysis (CHARDA) Assigns Charge State to Every Ion Peak.

Traditionally, mass spectrometry (MS) output is the ion abundance plotted versus the ionic mass-to-charge ratio m/z. While employing only commercially available equipment, Charge Determination Analysis (CHARDA) adds a third dimension to MS, estimating for individual peaks their charge states z starting from z = 1 and color coding z in m/z spectra. CHARDA combines the analysis of ion signal decay rates in the time-domain data (transients) in Fourier transform (FT) MS with the interrogation of mass defects (fractional mass) of biopolymers. Being applied to individual isotopic peaks in a complex protein tandem (MS/MS) data set, CHARDA aids peptide mass spectra interpretation by facilitating charge-state deconvolution of large ionic species in crowded regions, estimating z even in the absence of an isotopic distribution (e.g., for monoisotopic mass spectra). CHARDA is fast, robust, and consistent with conventional FTMS and FTMS/MS data acquisition procedures. An effective charge-state resolution Rz ≥ 6 is obtained with the potential for further improvements.

A High-Stretching, Rapid-Self-Healing, and Printable Composite Hydrogel Based on Poly(Vinyl Alcohol), Nanocellulose, and Sodium Alginate.

Hydrogels with excellent flexibility, conductivity, and controllable mechanical properties are the current research hotspots in the field of biomaterial sensors. However, it is difficult for hydrogel sensors to regain their original function after being damaged, which limits their practical applications. Herein, a composite hydrogel (named SPBC) of poly(vinyl alcohol) (PVA)/sodium alginate (SA)/cellulose nanofibers (CNFs)/sodium borate tetrahydrate was synthesized, which has good self-healing, electrical conductivity, and excellent mechanical properties. The SPBC0.3 hydrogel demonstrates rapid self-healing (<30 s) and achieves mechanical properties of 33.92 kPa. Additionally, it exhibits high tensile strain performance (4000%). The abundant internal ions and functional groups of SPBC hydrogels provide support for the good electrical conductivity (0.62 S/cm) and electrical response properties. In addition, the SPBC hydrogel can be attached to surfaces such as fingers and wrists to monitor human movements in real time, and its good rheological property supports three-dimensional (3D) printing molding methods. In summary, this study successfully prepared a self-healing, conductive, printable, and mechanically superior SPBC hydrogel. Its suitability for 3D-printing personalized fabrication and outstanding sensor properties makes it a useful reference for hydrogels in wearable devices and human motion monitoring.

Constructing a mesoporous carbon nanobowls embedded with ultrafine CoSe2 Nanocrystals for High-Performance potassium ion battery electrode

In the quest for advanced electrode materials for potassium ion batteries (KIBs), an innovative anode featuring ultrafine CoSe2 nanocrystals embedded within mesoporous carbon nanobowls (CoSe2@MCNBs) is presented herein. Diverging from conventional hollow carbon nanospheres, the distinctive bowl structure is crafted to enhance the structural integrity and volumetric energy density of the electrodes. CoSe2@MCNBs synthesized using an iterative drop and dry method followed by selenization exhibit well-preserved morphology with a shell thickness of 20 nm. The successful integration of ultrafine CoSe2 nanocrystals into MCNBs imparts the nanobowls with the benefits of conventional hollow carbon-based composites, including abundant ion storage sites and high electrical conductivity. Simultaneously, the bowl structure boasts a higher packing density than the conventional hollow mesoporous carbon sphere (HMCS) structure, significantly augmenting the volumetric energy density of the fabricated electrode. Capitalizing on these advantages, the CoSe2@MCNB electrode displays exceptional cycling stability, achieving a reversible capacity of 523 mA h g−1 after 500 cycles at 0.5 A/g and an impressive rate capacity of 247 mA h g−1 at 2.0 A/g. This study demonstrates the strong potential of CoSe2@MCNB as an electrode material for the next generation of KIBs.

Zinc- and Fluoride-Releasing Bioactive Glass as a Novel Bone Substitute

Bioglass 45S5, a silica-based glass, has pioneered a new field of biomaterials. Bioglass 45S5 promotes mineralization through calcium ion release and is widely used in the dental field, including toothpaste formulations. However, the use of Bioglass 45S5 for bone grafting is limited owing to the induction of inflammation, as well as reduced degradation and ion release. Phosphate-based glasses exhibit higher solubility and ion release than silica-based glass. Given that these glasses can be synthesized at low temperatures (approximately 1,000°C), they can easily be doped with various metal oxides to confer therapeutic properties. Herein, we fabricated zinc- and fluoride-doped phosphate-based glass (multicomponent phosphate [MP] bioactive glass) and further doped aluminum oxide into the MP glass (4% Al-MP glass) to overcome the striking solubility of phosphate-based glass. Increased amounts of zinc and fluoride ions were detected in water containing the MP glass. Doping of aluminum oxide into the MP glass suppressed the striking dissolution in water, with 4% Al-MP glass exhibiting the highest stability in water. Compared with Bioglass 45S5, 4% Al-MP glass in water had a notably reduced particle size, supporting the abundant ion release of 4% Al-MP glass. Compared with Bioglass 45S5, 4% Al-MP glass enhanced the osteogenesis of mouse bone marrow–derived mesenchymal stem cells. Mouse macrophages cultured with 4% Al-MP glass displayed enhanced induction of anti-inflammatory M2 macrophages and reduced proinflammatory M1 macrophages, indicating M2 polarization. Upon implanting 4% Al-MP glass or Bioglass 45S5 in a mouse calvarial defect, 4% Al-MP glass promoted significant bone regeneration when compared with Bioglass 45S5. Hence, we successfully fabricated zinc- and fluoride-releasing bioactive glasses with improved osteogenic and anti-inflammatory properties, which could serve as a promising biomaterial for bone regeneration.

A multi-omic survey of black cottonwood tissues highlights coordinated transcriptomic and metabolomic mechanisms for plant adaptation to phosphorus deficiency.

Phosphorus (P) deficiency in plants creates a variety of metabolic perturbations that decrease photosynthesis and growth. Phosphorus deficiency is especially challenging for the production of bioenergy feedstock plantation species, such as poplars (Populus spp.), where fertilization may not be practically or economically feasible. While the phenotypic effects of P deficiency are well known, the molecular mechanisms underlying whole-plant and tissue-specific responses to P deficiency, and in particular the responses of commercially valuable hardwoods, are less studied. We used a multi-tissue and multi-omics approach using transcriptomic, proteomic, and metabolomic analyses of the leaves and roots of black cottonwood (Populus trichocarpa) seedlings grown under P-deficient (5 µM P) and replete (100 µM P) conditions to assess this knowledge gap and to identify potential gene targets for selection for P efficiency. In comparison to seedlings grown at 100 µM P, P-deficient seedlings exhibited reduced dry biomass, altered chlorophyll fluorescence, and reduced tissue P concentrations. In line with these observations, growth, C metabolism, and photosynthesis pathways were downregulated in the transcriptome of the P-deficient plants. Additionally, we found evidence of strong lipid remodeling in the leaves. Metabolomic data showed that the roots of P-deficient plants had a greater relative abundance of phosphate ion, which may reflect extensive degradation of P-rich metabolites in plants exposed to long-term P-deficiency. With the notable exception of the KEGG pathway for Starch and Sucrose Metabolism (map00500), the responses of the transcriptome and the metabolome to P deficiency were consistent with one another. No significant changes in the proteome were detected in response to P deficiency. Collectively, our multi-omic and multi-tissue approach enabled the identification of important metabolic and regulatory pathways regulated across tissues at the molecular level that will be important avenues to further evaluate for P efficiency. These included stress-mediating systems associated with reactive oxygen species maintenance, lipid remodeling within tissues, and systems involved in P scavenging from the rhizosphere.

Investigating Ionization in the Intergalactic Medium

The intergalactic medium (IGM) contains >50% of the baryonic mass of the Universe, yet the mechanisms responsible for keeping the IGM ionized have not been fully explained. Hence, we investigate ion abundances from the largest blind QSO absorption catalog for clouds that show C iv, N v, and O vi simultaneously. The wavelength range of present UV spectrographs, however, makes it possible to probe C iv and O vi only over a small range of redshift (z ≈ 0.12–0.15). As a result, we only have five IGM absorbing clouds, yet these provide a powerful and representative tool to probe the IGM ionization state. We found one cloud to be in collisional ionization equilibrium while three of the five showed signs of being produced by nonequilibrium processes, specifically conductive interfaces and turbulent mixing layers. None of the models we explore here were able to reproduce the ionization state of the remaining system. Energetic processes, such as galactic feedback from star formation and active galactic nucleus winds, would be excellent candidates that can cause such widespread ionization.

Preparation of poly(lactic acid) (PLA)/poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV)/graphene oxide (GO) polymeric composites for the selective removal of lead ions (Pb(II)) in water

AbstractLead pollution in water has risen globally, due to industrialization and globalization. In this study, this problem was addressed by preparing poly (lactic acid) (PLA)/poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV)/graphene oxide (GO) composites and addressing their effectiveness in absorbing water, and adsorbing Pb(II) ions in water. In water absorption studies, increasing the GO content to above 1 wt.% (3 and 5 wt.%) resulted in the degradation of the composites. All blends, and composites with 1 wt.% GO loading showed good water intake properties, with the composites having the highest. Pb (II) ion intake analyses showed that all the materials adsorb Pb(II) ions significantly in 24 h contact time, but the composites with 1 wt.% GO loadings adsorbed the greatest (81.3%–86.5%). For the effect of pH on adsorption, the adsorption of Pb(II) ions increased with an increase in pH from acidic to basic. This was attributed to the abundance of hydroxyl ions in basic media, that will not compete with Pb(II) ions for adsorption sites. Conclusions were that the 49.5/49.5/1 w/w PLA/PHBV/GO composite was the most optimal adsorbent of Pb(II). This composite could be used in industrial water purification processes like membranes, to remove lead ions from water while conserving the environment.Highlights Melt mixed PLA/PHBV/GO composites for removing lead ions from water. 1 wt.% GO contents in the composites sufficiently absorbed water. 3 and 5 wt.% GO contents resulted in the hydrolytic degradation of composites. Contact time is directly proportional to the degree of lead ion adsorption. Basic pH media resulted in the optimal adsorption of lead ions from water.

NO3− loss from nitrate adducts of explosives by thermal decomposition in tandem Ion mobility spectrometry and by collision induced dissociation in tandem mass spectrometry

Nitrate adducts of nitroglycerin (NG) and 1,3-dinitroglycerin (1,3-DNG) were produced from atmospheric pressure chemical ionization with chloride reagent ions and in-source decomposition of M·Cl−. The nitrate adducts subsequently dissociated in the drift region with enthalpies of 109 ± 9 kJ mol −1 at 142–150 °C for NG·NO3− and 101 ± 8 kJ mol−1 at 161–173 °C for 1,3-DNG·NO3−. Similar behavior was not observed generally for other explosives although nitrate adducts of each explosive could be formed using electrospray ionization with a nitrate salt solution. Ion abundances were measured over a range of ion energies with collision induced dissociation in tandem mass spectrometry and models from Density Functional Theory were used to correlate the experimental findings to structural motifs and other adduct properties. The computational modeling showed that adduct stability is dominated by the electrostatic interaction between the nitrate ion and the dipole moment of the neutral explosive. Specifically, explosives having the ability to adapt a conformer with a large dipole moment showed the most stable adducts. Other binding contributions are possible yet were found to be minor in the explosive adducts studied here.

Compatibility and effect of capacity ratios between Na3V2(PO4)3 and hard carbon in highly concentrated sodium bis (fluorosulfonyl) imide electrolyte

From the standpoint of preserving the Earth's resources and ensuring the long-term viability of humanity, it is imperative to transition away from lithium-ion batteries. High-performance and safe sodium-ion batteries have recently emerged as promising advanced batteries for application in stationary energy storage, attributed to their low cost and abundance of sodium ion. We demonstrate the compatibility and effect of the negative-positive capacity ratio in full-cell Na3V2(PO4)3 and hard carbon in high-concentration electrolytes. Thanks to the excellent oxidation stability of the electrolyte, during 100 cycles, the full cell with a negative-positive capacity ratio of 1.1 demonstrated a consistent capacity of around 100 mAh g-1 with a capacity retention of 90.7%, whereas the full cell with a ratio of 1.0 showed a steady discharge capacity of roughly 90 mAh g-1 with a capacity retention of approaching 100% at a current density of C/5.

Abstract 6850: Unraveling molecular factors contributing to metallomic dyshomeostasis induced by triple-negative breast cancer using single-cell RNA sequencing

Abstract Triple-negative breast cancer (TNBC) comprises 20% of breast cancer cases and exhibits an aggressive phenotype with increased metastasis; these patients have limited treatment options, poorer prognosis and higher mortality than other breast cancers (BC). Metallomics is a relatively new discipline that studies the abundance of metal ions in biological samples. Metallomic analysis has identified differences in BC patients in elements such as iron (Fe) and zinc (Zn) but it is unclear if these reflect metabolic changes in the tumor. In this study, we conducted metallomic profiling to characterize 55 trace elements in the circulation and in the tumor microenvironment of orthotopic mammary fat pad tumors from two isogenic BC cell lines (highly metastatic 4T1; nonmetastatic 67NR). We complemented this analysis with single-cell RNA sequencing of the tumor to determine if complementary changes occur in molecules known to utilize metals as co-factors or transporters and identify drivers of metal metabolism in different tumors. We performed analysis on systemic metal elements by examining whole blood (including blood cells and platelets) and plasma separately. Tumor samples were assessed at the whole tissue level, and we also profiled separated immune or non-immune cells from the tumor. Li, Na, Mg, P, S, K, Ca, Fe, Cu, Zn, Rb were detectable within 100ul of input of whole blood or plasma. Metallomic analysis of the tumor and associated cell populations detected differential levels of Na, Mg, P, S, K Ca, Fe, Zn, and Rb from an average of 200mg of tissue or 2 million cells. Based on scRNAseq analysis, 67NR tumors were composed of greater proportions of cancer cells relative to the 4T1 tumors (79.1% vs 58.8% of tumor cells respectively) and endothelial cells (2.5% vs 1.8%). 4T1 tumors contained an increased abundance of cancer-associated fibroblasts (5.6% vs 2.1%) as well as immune infiltration (33.8% vs 16.3%). Fibroblasts and macrophage populations also showed elevated metal transporter expression levels based on gene expression relative to other tumor residing cell types yet minor differences induced by cancer type. Cancer cells express high levels of metal transport genes (Zn, Ca, Co, Na, Mg, Fe). 67NR cancer cells exhibited increased gene expression of many metal-transporting proteins including numerous solute carrier (SLC) group of membrane transport proteins such as Slc41a2 when compared to the more aggressive 4T1 cells. This study underscores the potential of linking metallomic profiling to tumor composition and cancer behaviors, offering a pathway for identifying novel biomarkers to differentiate aggressive and non-aggressive forms of breast cancer. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Citation Format: Nicholas R. Hum, John M. Rolison, Nicole F. Leon, Ali Navid, Aimy Sebastian, Josh Wimpenny, Gabriela Loots. Unraveling molecular factors contributing to metallomic dyshomeostasis induced by triple-negative breast cancer using single-cell RNA sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6850.

Three-Dimensional Self-Supported Ge Anode for Advanced Lithium-Ion Batteries.

Three-dimensional (3D) self-supported Ge anode is one of the promising candidates to replace the traditional graphite anode material for high-performance binder-free lithium-ion batteries (LIBs). The enlarged surface area and the shortened ions/electrons transporting distance of the 3D electrode would greatly facilitate the rapid transfer of abundant lithium ions during cycling, thus achieve enhanced energy and power density during cycling. Cycle stability of the 3D self-supported Ge electrode would be improved due to the obtained enough space could effectively accommodate the large volume expansion of the Ge anode. In this review, we first describe the electrochemical properties and Li ions storage mechanism of Ge anode. Moreover, the recent advances in the 3D self-supported Ge anode architectures design are majorly illustrated and discussed. Challenges and prospects of the 3D self-supported Ge electrode are finally provided, which shed light on ways to design more reliable 3D Ge-based electrodes in energy storage systems.

Formation of multiple ion types during MALDI imaging mass spectrometry analysis of Mitragyna speciosa alkaloids in dosed rat brain tissue

Mitragyna speciosa, more commonly known as kratom, has emerged as an alternative to treat chronic pain and addiction. However, the alkaloid components of kratom, which are the major contributors to kratom's pharmaceutical properties, have not yet been fully investigated. In this study, matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry was used to map the biodistribution of three alkaloids (corynantheidine, mitragynine, and speciogynine) in rat brain tissues. The alkaloids produced three main ion types during MALDI analysis: [M + H]+, [M − H]+, and [M − 3H]+. Contrary to previous reports suggesting that the [M − H]+ and [M − 3H]+ ion types form during laser ablation, these ion types can also be produced during the MALDI matrix application process. Several strategies are proposed to accurately map the biodistribution of the alkaloids. Due to differences in the relative abundances of the ions in different biological regions of the tissue, differences in ionization efficiencies of the ions, and potential overlap of the [M − H]+ and [M − 3H]+ ion types with endogenous metabolites of the same empirical formula, a matrix that mainly produces the [M + H]+ ion type is optimal for accurate mapping of the alkaloids. Alternatively, the most abundant ion type can be mapped or the intensities of all ion types can be summed together to generate a composite image. The accuracy of each of these approaches is explored and validated.

High-energy CID tandem TOF-MS of various types of precursor ions of selected diether phospholipids: Diagnostic known and unexpected fragmentation pathways

The fragmentation behavior of some selected synthetic (1,2-diphytanyl- and 1,2-dihexadecyl-glycerophosphatidylethanolamine, 1,2-diphytanyl- and 1,2-dihexadecyl-glycerophosphatidylcholine) as well as of one natural diether phospholipid (2,3-diphytanyl-glycerophosphatidylinositol), the latter obtained from extracts of the archaeon Sulfolobus acidocaldaricus, was described by negative- and positive-ion MALDI high-energy CID tandem time-flight mass spectrometry for the first time. In contrast to the fragmentation pathways of classical diester glycerophospholipids, whose fragmentation behavior is already well described, the investigated diether glycerophospholipids exhibited a very different fragmentation behavior. The [M–H]−-precursor ions (ethanolamine, inositol) showed abundant high-mass charge-remote site fragmentation of the alkyl chains with easy determination of all methyl branching points (if present). Corresponding low mass product ions elucidated the identity of the polar head group. In contrast, [M+H]+-precursor ions of ethanolamine derivatives showed unusual loss of H3PO4 directly from the precursor ion and McLafferty-like rearrangements of selected product ions differing between sn1-and sn2-substituents, [R1O+58]+ and [R2O+42]+ ions, respectively. No diagnostic low mass product ions or high mass charge-remote site fragmentations are observed. A yet undescribed rearrangement reaction for protonated diether phosphocholine derivates was found by an intramolecular transesterification rearrangement of the precursor ion forming protonated O-alkyl glycerophosphatidylcholine. Besides, high mass charge-remote site fragmentation of the alkyl chains was observed. High-energy CID-spectra of [M+Na]+-precursor ions showed only little fragmentation (ethanolamine, inositol) with abundant partial polar head group losses and low mass head group product ions. In contrast, the [M+Na]+-precursor ions of corresponding choline derivatives showed significant charge-remote site fragmentation of the alkyl chains and diagnostic low mass head group ions. In case of the ethanolamine derivatives the [M+2Na–H]+-precursor ions exhibited abundant polar head group losses and high mass charge-remote site fragmentation with diagnostic low mass head group product ions. The inositol derivative mainly yielded disodiated dehydrated inositol phosphate as product ions. Finally, two diether phospholipid-specific product ions, the newly described K- and L-type ions, are described for the first time for all lipid derivatives and their mechanism of formation is described in detail.

Superstructured Optoionic Heterojunctions for Promoting Ion Pumping Inspired by Photoreceptor Cells.

Photoreceptor cells of vertebrates feature ultrastructural membranes interspersed with abundant photosensitive ion pumps to boost signal generation and realize high gain in dim light. In light of this, superstructured optoionic heterojunctions (SSOHs) with cation-selective nanochannels are developed for manipulating photo-driven ion pumping. A template-directed bottom-up strategy is adopted to sequentially assemble graphene oxide (GO) and PEDOT:PSS into heterogeneous membranes with sculptured superstructures, which feature programmable variation in membrane topography and contain a donor-acceptor interface capable of maintaining electron-hole separation upon photoillumination. Such elaborate design endows SSOHs with a much higher magnitude of photo-driven ion flux against a concentration gradient in contrast to conventional optoionic membranes with planar configuration. This can be ascribed to the buildup of an enhanced transmembrane potential owing to the effective separation of photogenerated carriers at the heterojunction interface and the increase of energy input from photoillumination due to a synergistic effect of reflection reduction, broad-angle absorption, and wide-waveband absorption. This work unlocks the significance of membrane topographies in photo-driven transmembrane transportation and proposes such a universal prototype that could be extended to other optoionic membranes to develop high-performance artificial ion pumps for energy conversion and sensing.

Customized anion-exchange covalent organic frameworks for efficient extraction of natural products

Extracting highly value-added products from natural systems with low concentrations and complex constituents is of great significance but remains a massive challenge. Herein, a series of dual-functional covalent organic frameworks with both anion exchange and pore adsorption abilities are designed and fabricated using the quaternary amine monomer doping strategy. Attributed to abundant ion exchange sites and selective pore adsorption, the COFs demonstrate high selectivity and loading capacity and fast adsorption for natural products (glycyrrhetinic acid, a high-value natural product), surpassing commercially available materials. Additionally, high-purity (>99%) glycyrrhetinic acid with a >90% extraction efficiency from natural fermentation systems is successfully achieved using a solid-phase extraction column with COFs as the separation medium. The separation column demonstrates outstanding reusability and reproducibility, providing great potential for COFs to serve as robust separation mediums for challenging natural product purification.

Three-Dimensional Vanadium and Nitrogen Dual-Doped Ti3C2 Film with Ultra-High Specific Capacitance and High Volumetric Energy Density for Zinc-Ion Hybrid Capacitors.

Zinc-ion hybrid capacitors (ZICs) can achieve high energy and power density, ultralong cycle life, and a wide operating voltage window, and they are widely used in wearable devices, portable electronics devices, and other energy storage fields. The design of advanced ZICs with high specific capacity and energy density remains a challenge. In this work, a novel kind of V, N dual-doped Ti3C2 film with a three-dimensional (3D) porous structure (3D V-, N-Ti3C2) based on Zn-ion pre-intercalation can be fabricated via a simple synthetic process. The stable 3D structure and heteroatom doping provide abundant ion transport channels and numerous surface active sites. The prepared 3D V-, N-Ti3C2 film can deliver unexpectedly high specific capacitance of 855 F g-1 (309 mAh g-1) and demonstrates 95.26% capacitance retention after 5000 charge/discharge cycles. In addition, the energy storage mechanism of 3D V-, N-Ti3C2 electrodes is the chemical adsorption of H+/Zn2+, which is confirmed by ex situ XRD and ex situ XPS. ZIC full cells with a competitive energy density (103 Wh kg-1) consist of a 3D V-, N-Ti3C2 cathode and a zinc foil anode. The impressive results provide a feasible strategy for developing high-performance MXene-based energy storage devices in various energy-related fields.