Insight into the Mechanism of Cobalt-Nickel Separation Using DFT Calculations on Ethylenediamine-Modified Silica Gel.

The separation of Co(II) and Ni(II) from leaching solution is gaining interest because Co(II) and Ni(II) are increasingly used in emerging strategic areas, such as power batteries. Herein, the surface of silica gel is functionalized with 1,2-ethylenediamine and used for the separation of Co(II) and Ni(II). The Co(II) removal efficiency of the modified silica is 80.2%, with a 4-fold improvement in the separation factor. The geometry, frequency, and electrostatic potential of the ethylenediamine modified silica gel (en/SG) are calculated. The corresponding properties of M2+ (M-Co, Ni) adsorbed on en/SG in an aqueous solution are simulated and analyzed. The results show that ethylenediamine tends to form [Men(H2O)4]2+ after binding to M2+, and the binding ability of Co(II) to ethylenediamine is stronger. Besides, the thermodynamic calculations show that en/SG has a more negative Gibbs free energy when absorbing Co(II) in aqueous solution, so en/SG is more inclined to bind with Co(II) preferentially. It is the difference in complexation ability between Ni, Co, and ethylenediamine that enlarges the difference in the original physical adsorption, thus strengthening the separation performance. This work will provide guidance for a rational design of high-performance nickel-cobalt adsorption materials.

Structural N-glycoproteomics characterization of cell-surface N-glycosylation of MCF-7/ADR cancer stem cells.

Breast cancer is responsible for the highest mortality all over the world. Cancer stem cells (CSCs) along with epithelial mesenchymal transition (EMT) are identified as a driver of cancer which are responsible for cancer metastasis and drug resistance. Several signaling pathways are associated with drug resistance. Additionally, glycosyltransferases regulate different types of glycosylation which are involved in drug resistance. To the end, it is urgent to figure out the knowledge on cell-surface altered N-glycosylation and putative markers. Here, differential cell-surface intact N-glycopeptides in adriamycin (ADR)-resistant michigan breast cancer foundation-7 stem cells (MCF-7/ADR CSCs) relative to ADR-sensitive MCF-7 CSCs were analyzed with site- and structure-specific quantitative N-glycoproteomics. The intact N-glycopeptides and differentially expressed intact N-glycopeptides (DEGPs) were determined and quantified via intact N-glycopeptide search engine GPSeeker. Totally, 4777 intact N-glycopeptides were identified and N-glycan sequence structures among 2764 IDs were distinguished from their isomers by structure-diagnostic fragment ions. Among 1717 quantified intact N-glycopeptides, 104 DEGPs were determined (fold change ≥ 1.5 and p value < 0.05). Annotation of protein-protein interaction and biological processes among others of DEGPs were finally carried out; down-regulated intact N-glycopeptide with bisecting GlcNAc from p38-interacting protein and up-regulated intact N-glycopeptide with ß1,6-branching N-glycan from integrin beta-5 were found.

Tailored nitrogen-defect induced by diels-alder reaction for enhanced electrochemical hydrogen evolution reaction.

Electrocatalytic water splitting in an alkaline medium is recognized as the promising technology to sustainably generate clean hydrogen energy via hydrogen evolution reaction (HER), while the sluggish water dissociation and subsequent *H adsorption steps greatly retarded the reaction kinetics and efficiency of the overall hydrogen evolution process. Whilst nitrogen (N)-doped carbon-based materials are attractive candidates for promoting HER activity, the facile fabrication and gaining a deeper insight into the electrocatalytic mechanism are still challenging. Herein, inspired by the Diels-Alder reaction, we precisely tailored six-membered pyridinic N and five-membered pyrrolic N sites at the edge of the carbon substrates. Comprehensive analysis validates that the participation of pyridinic N (electron-withdrawing) and pyrrolic N (electron-releasing) will induce the charge rearrangements, and further generate local electrophilic and nucleophilic domains in adjacent carbon rings, which guarantees the occurrence of water dissociation to generate protons and the subsequent adsorption of *H intermediates through electrostatic interactions, thereby facilitating the overall reaction kinetics. To this end, the optimal NC-ZnCl2-25 % electrocatalysts present excellent alkaline HER activity (η10 = 45 mV, Tafel slop of 37.7 mV dec-1) superior to commercial Pt/C.

Sialic acid linkage-specific quantitative N-glycoproteomics using selective alkylamidation and multiplex TMT-labeling.

Protein sialylation participates many biological processes in a linkage-specific manner, and aberrant sialylation has been associated with many malignant diseases. Mass spectrometry-based quantitative N-glycoproteomics has been widely adopted for quantitative analysis of aberrant sialylation, yet multiplexing method at intact N-glycopeptides level is still lacking. Here we report our study of sialic acid linkage-specific quantitative N-glycoproteomics using selective alkylamidation and multiplex tandem mass tags (TMT)-labeling. With lung cancer as a model system, differential sialylation in cancer tissues relative to adjacent non-tumor tissues was characterized at the intact N-glycopeptide level with N-glycosite information. TMT-labeled intact N-glycopeptides with and without sialic acid alkylamidation were subject to reversed-phase liquid chromatography-nano-electron spray ionization-tandem mass spectrometry (RPLC-nanoESI-MS/MS) analysis to provide comprehensive characterization of N-glycosylation with and without sialic acid at the intact N-glycopeptide level with structure and N-glycosite. In this study, 6384 intact N-glycopeptides without sialylation were identified and 521 differentially expressed intact N-glycopeptides from 254 intact N-glycoproteins were quantified. Eight intact N-glycoproteins responsible for N-glycan biosynthesis were identified as glycosyltransferases. In total, 307 sialylated intact N-glycopeptides with linkage-specific sialic acid residues were identified together with 29 N-glycans with α2,6-linked sialic acids and 55 N-glycans with α2,3-linked sialic acids. Intact N-glycoproteins with α2,6-sialylation were associated with coronavirus disease-(COVID)-19. Additionally, many types of N-glycosylation including terminal N-galactosylation, core and/or branch fucosylation, α2,6-sialylation and terminal bisecting N-acetylglucosamine were identified and quantified in intact N-glycoproteins from immunoglobulin family.

Open-Framework Metal Oxides for Fast and Reversible Hydrated Zinc-Ion Intercalation.

The development of high capacity and stable cathodes is the key to the successful commercialization of aqueous zinc-ion batteries. However, significant solvation penalties limit the choice of available positive electrodes. Herein, hydrated intercalation is proposed to promote reversible (de)intercalation within host materials by rationally designing a matching electrode. In contrast to previously reported works, the as-prepared electrode (NHVO@CC) can achieve fast and reversible intercalation of hydrated zinc ions in the interlayer gap, leading to a high capacity of 517 mAh g-1 at 0.1 A g-1 and excellent electrode stability for long-term cycling. Besides, as a consequence of the flexibility of the NHVO@CC electrode, a quasi-solid-state battery was achieved with equally advantageous electrochemical behavior under various bending states. The proposed hydrated cation direct insertion/extraction sets up an efficient way of developing high-performance positive electrodes for aqueous batteries.

Quantitative tuning of ionic metal species for ultra-selective metal solvent extraction toward high-purity vanadium products.

The essence behind metal solvent extraction is the interaction between metal species and organic extractants. Aqueous metal species tuning at the molecular level is critical to improve the extraction efficiency and selectivity of the target metal. Herein, we demonstrate a quantitative metal species tuning strategy which is capable of extracting the most critical metals (e.g., V, W, and Mo) in extraction systems constructed by amines. We reveal the superior activities of V4 and V10 species among various V and Cr species by calculations and experiments. In addition, the contribution of various Vn species was quantitatively evaluated via Ion Species Contribution Evaluation (ISCE). Our tuning strategy is rationally designed by bridging species characteristics and routine aqueous conditions with extraction activities. Consequently, a three-dimensional model of V and Cr solvent extraction is established for the prediction of reaction regions, and the reactivities of nearly 20 kinds of typical metal species are compared and predicted. Our strategy serves for industrial solvent extraction, and may provide inspiration for the traditional hydrometallurgical revolutionary.

Putative N-glycoprotein markers of MCF-7/ADR cancer stem cells from N-glycoproteomics characterization of the whole cell lysate.

Breast cancer is one of the most malignant diseases among females. N-glycoproteomics studies have shown that N-glycosylation alteration of tumor cells is the key player of cancer progression, multidrug resistance (MDR) and high mortality. Cancer stem cells (CSCs) have the remarkable potential of self-renewing and differentiation which leads to drug resistance and metastasis. To investigate the differentially expressed N-glycosylation in adriamycin-resistant breast cancer stem cells MCF-7/ADR CSCs (relative to MCF-7 CSCs) and find the putative biomarkers, 1:1 paired ZIC-HILIC-enriched and stable isotopic diethyl labelled (SIDE) intact N-glycopeptides from MCF-7/ADR CSCs and MCF-7 CSCs were analyzed with C18-RPLC-ESI-MS/MS (HCD with stepped NCE); differentially expressed intact N-glycopeptides (DEGPs) were identified and quantified via search engine GPSeeker. With control of spectrum-level FDR≤1%, 5515 intact N-glycopeptides were identified (1737 N-glycosites, 1705 peptide backbones and 1516 intact N-glycoproteins; 181 putative N-glycan linkages and 68 monosaccharide compositions). Among 5515 intact N-glycopeptide IDs, 3864 were identified with glycoform score≥1, i.e., one or more structure-diagnostic fragment ions were observed to distinguish sequence isomers. With the three technical replicates and the criteria of fold change≥1.5 and p value<0.05, 380 DEGPs (corresponding to 153 intact N-glycoproteins) were found along with 293 down-regulated and 87 up-regulated. For these 153 intact N-glycoproteins, the molecular functions and biological processes of were comprehensively discussed, and side-to-side comparison of differential expression results with other method were also made.

N-Glycoproteomics Study of Putative N-Glycoprotein Biomarkers of Drug Resistance in MCF-7/ADR Cells.

Currently, drug resistance of anti-cancer therapy has become the main cause of low survival rate and poor prognosis. Full understanding of drug resistance mechanisms is an urgent request for further development of anti-cancer therapy and improvement of prognosis. Here we present our N-glycoproteomics study of putative N-glycoprotein biomarkers of drug resistance in doxorubicin resistance breast cancer cell line michigan cancer foundation-7 (MCF-7/ADR) relative to parental michigan cancer foundation-7 (MCF-7) cells. Intact N-glycopeptides (IDs) from MCF-7/ADR and MCF-7 cells were enriched with zwitterionic hydrophilic interaction liquid chromatography (ZIC-HILIC), labeled with stable isotopic diethylation (SIDE), and analyzed with C18-RPLC-MS/MS (HCD with stepped normalized collision energies); these IDs were identified with database search engine GPSeeker, and the differentially expressed intact N-glycopeptides (DEGPs) were quantified with GPSeekerQuan. With target-decoy searches and control of spectrum-level FDR ≤ 1%, 322 intact N-glycopeptides were identified; these intact N-glycopeptides come from the combination of 249 unique peptide backbones (corresponding to 234 intact N-glycoproteins) and 90 monosaccharide compositions (corresponding to 248 putative N-glycosites). The sequence structures of 165 IDs were confirmed with structure-diagnostic fragment ions. With the criteria of observation at least twice among the three technical replicates, ≥ 1.5-fold change and p value < 0.05, 20 DEGPs were quantified, where five of them were up-regulated and 15 of them were down-regulated; the corresponding intact N-glycoproteins as putative markers of drug resistance were discussed. Supplementary Information: The online version contains supplementary material available at 10.1007/s43657-021-00029-8.

Mass spectrometry-based qualitative and quantitative N-glycomics: An update of 2017-2018.

N-glycosylation is one of the most frequently occurring protein post-translational modifications (PTMs) with broad cellular, physiological and pathological relevance. Mass spectrometry-based N-glycomics has become the state-of-the-art instrumental analytical pipeline for sensitive, high-throughput and comprehensive characterization of N-glycans and N-glycomes. Improvement and new development of methods in N-glycan release, enrichment, derivatization, isotopic labeling, separation, ionization, MS, tandem MS and informatics accompany side-by-side wider and deeper application. This review provides a comprehensive update of mass spectrometry-based qualitative and quantitative N-glycomics in the years of 2017-2018.

Design of injectable agar-based composite hydrogel for multi-mode tumor therapy.

We designed an injectable hydrogel by dissolving MoS2/Bi2S3-PEG (MBP), doxorubicin (DOX) and agar into water for the concurrent tumor photothermal and chemotherapy. The formed solution was able to be intra-tumorally (I.T.) administered into tumor at a relatively high temperature and automatically formed a hydrogel after cooling to body temperature. The resultant Agar/MBP/DOX (AMD) hydrogel can act as a macro-vessel to retain the MBP nanosheet and DOX and restrict their access to body fluid circulation. Moreover, AMD hydrogel did not compromise the photoacoustic and computed tomography imaging capacity, as well as the photothermal and chemotherapy efficiency of MBP nanosheets and DOX. The heat from the photothermal transformation of MBP nanosheet can promote the drug-release from the hydrogel and thus enable an on-demand drug release. Furthermore, antibiotics were also able to be encapsulated in the hydrogel to avoid the potential wound infection during tumor surgery.

Bottom-up synthesis of WS2 nanosheets with synchronous surface modification for imaging guided tumor regression.

Two-dimensional transition metal dichalcogenides (TMDs) have been receiving great attention as NIR photothermal transducing agent in tumor photothermal therapy. Keeping in mind the low efficiency of the conventional top-down exfoliated 2D TMDs and the complexity of their surface modifications, we herein proposed a bottom-up strategy for the one-pot hydrothermal and controlled synthesis of surface polyvinyl pyrrolidone (PVP) modified WS2 nanosheets. The material design was based on the chelating-coordinating effect between the lone pair electrons of oxygen of PVP carbonyl group and the unoccupied orbital (5d orbitals) of tungsten. The WS2 nanosheets with synchronous surface PVP grafting showed an excellent photothermal conversion performance, while the surface anchored PVP guaranteed its colloidal stability. Moreover, the strong X-ray attenuation ability and near-infrared (NIR) absorbance of WS2-PVP360kDa enabled the sensitive in vitro and in vivo computed tomography and photoacoustic imaging. The WS2-PVP360kDa nanosheets were biocompatible and exhibited promising in vitro and in vivo anti-cancer efficacy. Findings in this report may greatly promote the design of colloidal stable and biocompatible 2D TMDs and their future clinical translations. STATEMENT OF SIGNIFICANCE: A bottom-up strategy for the one-pot and controlled synthesis of surface polyvinyl pyrrolidone (PVP) modified WS2 nanosheets was proposed for the first time. By hydrothermally treating the mixture solution of tetrathiotungstate and PVP, Owing to the chelating-coordinating effect between the lone pair electrons of oxygen of PVP carbonyl group and the unoccupied orbital (5d orbitals) of tungsten, PVP was synchronously graphed on WS2-PVP nanosheets surface. The formed WS2-PVP nanosheets were colloidal stable, biocompatible, and exhibited promising computed tomography, photoacoustic imaging and tumor photothermal therapy efficacy both in vitro and in vivo.

Analysis of miRNAs and their targets during adventitious shoot organogenesis of Acacia crassicarpa.

Organogenesis is an important process for plant regeneration by tissue or cell mass differentiation to regenerate a complete plant. MicroRNAs (miRNAs) play an essential role in regulating plant development by mediating target genes at transcriptional and post-transcriptional levels, but the diversity of miRNAs and their potential roles in organogenesis of Acacia crassicarpa have rarely been investigated. In this study, approximately 10 million sequence reads were obtained from a small RNA library, from which 189 conserved miRNAs from 57 miRNA families, and 7 novel miRNAs from 5 families, were identified from A. crassicarpa organogenetic tissues. Target prediction for these miRNAs yielded 237 potentially unique genes, of which 207 received target Gene Ontology annotations. On the basis of a bioinformatic analysis, one novel and 13 conserved miRNAs were selected to investigate their possible roles in A. crassicarpa organogenesis by qRT-PCR. The stage-specific expression patterns of the miRNAs provided information on their possible regulatory functions, including shoot bud formation, modulated function after transfer of the culture to light, and regulatory roles during induction of organogenesis. This study is the first to investigate miRNAs associated with A. crassicarpa organogenesis. The results provide a foundation for further characterization of miRNA expression profiles and roles in the regulation of diverse physiological pathways during adventitious shoot organogenesis of A. crassicarpa.