Simultaneous Enrichment Research Articles

Nickel-Coated ceramic hollow fiber cathode for fast enrichment of chemolithoautotrophs and efficient reduction of CO2 in microbial electrosynthesis

Microbial electrosynthesis (MES) explores the potential of chemolithoautotrophs for the production of value-added products from CO2. However, the enrichment of chemolithoautotrophs on a cathode is relatively slow and the separation of the products is energy intensive. In this study, a novel and multifunctional cathode configuration, enabling the simultaneous enrichment of chemolithoautotrophs and separation of acetate from MES, was developed through one-step electroless nickel plating on ceramic hollow fiber (CHF) membrane. A thick layer of chemolithoautotrophs with 5.2 times higher cell density, which was dominated by Sporomusa (68 % of the total sequence reads in biocathode), was enriched on the membrane cathode surface through suspended biomass microfiltration compared to MES reactors operated without filtration. Simultaneously, >87 % of acetate (31 mM) per batch could be harvested after catholyte microfiltration. The Ni content was > 80 % on the CHF surface after long-term operation in the two-chamber MES system, which exhibited 78 % lower charge transfer resistance compared to three-chamber MES system (∼110 vs 510 Ω) for acetate separation/extraction. The ease of product separation in two-chamber MES systems and the fast establishment of chemolithoautotrophs on the cathode are a step forward in realizing MES systems as a promising platform for CO2 reduction and biochemical production in a circular carbon bioeconomy.

Feammox in alluvial-lacustrine aquifer system: Nitrogen/iron isotopic and biogeochemical evidences

Groundwater nitrogen contamination is becoming increasingly serious worldwide, and natural nitrogen attenuation processes such as anaerobic ammonium oxidation coupled to iron reduction (“Feammox”) play an important role in mitigating contamination. Although there has been intensive study of Feammox in soils and sediments, still lacks research on this process in groundwater. This study makes effort to demonstrate the occurrence of Feammox in groundwater by combining information from Fe/N isotope composition, the quantitative polymerase chain reaction (qPCR) assay, and 16S rRNA gene sequencing. Poyang Lake Plain of Yangtze River in central China was selected as the case study area. The critical evidences that indicate Feammox in groundwater include favorable hydrogeochemical conditions of the alluvia-lacustrine aquifer systems, the simultaneous enrichment of 15N in ammonium and 56Fe, the relative high abundance of Acidimicrobiaceae bacterium A6, and the joint elevation of the abundance of the Feammox bacteria and the concentration of Fe(III). Redundancy analysis (RDA) indicated that Geothrix and Rhodobacter may participate directly or cooperatively in the Feammox process. Ammonium-oxidizing archaea (AOA) involved in ammonium-oxidizing or Feammox process may be stimulated by Fe(III) under a low oxygen concentration and weakly acidic condition. Anammox may be indirectly enhanced by products of the nitrogen transformation processes involving Feammox bacteria and AOA. Fe(III) concentration is an important environmental factor affecting the abundance of functional microorganisms related to nitrogen cycling and the composition of ammonium-oxidizing and iron-reducing microbes. Specific geological background (such as the widespread red soils) and anthropogenic input of ammonium, iron, and acidic substances may jointly promote Feammox in groundwater.

53. Wound Edge Inversion Delays Healing and Contributes to Dystrophic Scar Formation in a Mouse Model

Purpose: Management of dystrophic scars often requires surgical excision in the delayed periods as there are few reliable options to prophylax against the formation off dystrophic scars during physiologic or pathologic wound healing. This is in part because of limitations in the availability of genetically tractable small-animal models which can reliably generate the desired dystrophic tissue architecture. While using small animal models of wound healing is desired, the nature of murine dermal healing through contracture makes it poorly suited to the study of later wound sequalae such as dystrophic scars. We have previously demonstrated that tissue-edge inward folding mimicking the architecture of epibole mitigates contracture, restricts epithelialization, and prolongs wound opening. Here we demonstrate that murine epibolous wounds generate an environment of sustained inflammatory infiltration and proliferative granulation and ultimately generate consistent and reliable dystrophic scars in mice. Methods: Male C57BL/6J control (wt/wt) and diabetic (db/db) mice received bilateral 6mm excisional wounds. Each wound was stratified as either untreated control or chronic model. Chronic wounds were generated by incising skin flaps, which were sutured to the dermis side to create a folded skin edge. A first (acute) cohort was s were maintained for 14-days until all control wounds had closed and/or epithelialized and were harvested for flow cytometry for neutrophils and/or macrophages and/or histology for pan-keratin (epithelium) and alpha-smooth-muscle actin (myofibroblasts). A second (delayed) cohort was maintained until closure up to 63 days. Photographs were taken at time of sacrifice and samples were collected for H&E and Masson’s Trichrome Stain. Results: The epibolous wound environment maintained prolonged neutrophil-dominant inflammatory infiltrate up to 2-weeks with simultaneous enrichment of macrophage/monocyte populations (p<0.05). Epibolous wounds demonstrated reduced frequency of epithelialization as defined by pan-keratin signaling. In epibolous wounds without epithelialization, strong alpha-smooth-muscle actin signal was noted. When allowed to proceed to maturation, scars from epibole injuries remained significantly larger (p<0.05). This was true in both control and diabetic models. All wound-edge inversion injuries demonstrated gross and histologic evidence of dystrophic healing and collagen deposition compared to controls. Conclusion: Previously we demonstrated that wound-edge inversion to mimic epibole prolongs wound opening. Here we demonstrate that this translates to prolongs inflammation and a transition of murine healing to a more human-relevant granulation pattern. Furthermore, the delay of closure results in a consistent dystrophic scar without need for thermal, radiological, chemical or biological interference. Consequently, this simple surgical maneuver enhances our ability to study and intervene in the process of acute and chronic wound development and dystrophic scar formation in a histologically humanized model while retaining access to the genetic tractability of murine stock.

Temperature-responsive surfactant-free microemulsion solvent: Preparation, characterization and application of extraction hydrophobic and hydrophilic components in plant matrix

In this study, a novel temperature responsive surfactant-free microemulsion (SFME) solvent was prepared and fully characterized. Combined with ultrasonic assisted extraction (UAE), it was applied to the simultaneous extraction and enrichment of different hydrophilic and hydrophobic components in Rosa roxburghii leaves. The extraction factors such as solid-liquid ratio, extraction temperature and extraction time were optimized by response surface methodology. The extraction yields of components with different polarity were improved by 1.03–3.90 folds compared with traditional solvents. The extraction mass transfer process was fitted by first-order kinetic model and second-order kinetic model. The results showed that the fitting effect of second-order kinetic model was better. Moreover, molecular dynamics revealed that hydrogen bonds were formed between the solvent and the compound molecules then promoted the improvement of extraction capacity. Notably, in situ separation and recovery of compounds with different polarities were conducted by SFME and the recovered extracts had good antioxidant capacity. In conclusion, this novel SFME was environment-friendly and simultaneously appropriate for the effective extraction and enrichment of natural active compounds from plant matrix.

Abstract 810: HRD is inversely correlated with MSI and identifies immunologically cold tumors in most cancer types

Abstract Homologous recombination deficiency (HRD) leads to DNA double strand breaks and can be exploited by the use of PARP inhibitors to induce synthetic lethality of cancer cells. Over the last years, the clinical utility of this therapeutic concept was successfully demonstrated in ovarian, breast, prostate and pancreatic cancer. Currently, the role of HRD is investigated in trials testing immune checkpoint blockers alone or in combination with PARP inhibitors. But the relationship between HRD and immune cell contexture in cancer is incompletely understood. Here, we analyzed the association of HRD with tumor mutational burden (TMB), immune cell composition and gene expression in 10,000 tumors of 32 solid cancer types from the TCGA project. For each of the tumors, the HRD sum score (HRDsum) was calculated from allele-specific copy numbers (derived from genotyping data) and the TMB was calculated from the missense mutation calls (derived from WES data). HRDsum and tumor mutational burden (TMB) correlated positively pan-cancer (R=0.42) and within most cancer types. By contrast, HRD was absent in ultra-hypermutated (TMB &amp;gt;= 100 mut/Mb) tumors. Ultra-hypermutation was typically associated with microsatellite instability (MSI) or POLE/POLD1 mutation. Significant positive correlation of the HRDsum and immune cell infiltration was observed pan-cancer, but only within a few cancer types. Significant positive correlation of HRDsum and the T-cell inflamed gene expression profile was observed only in 7 of 32 cancer types: in breast cancer, ovarian cancer, low grade glioma, testicular germ cell tumors and three kinds of kidney cancer. A functional genomics analysis was carried out by correlating genome-wide gene expression data (derived from RNA-Seq) with HRDsum. The resulting lists of significantly correlating genes were analyzed for enrichment of 50 hallmark gene sets (catalog H, MSigDB). We detected simultaneous enrichment of two proliferation-related categories, E2F_TARGETS and G2M_checkpoint, for 13 of the 32 cancer types (ACC, BLCA, BRCA, KIRC, KIRP, LGG, LIHC, LUAD, LUSC, MESO, PRAD, SARC, THYM). The study shows that HRD is associated with immunological activation of the tumor microenvironment only in a minority of cancer types. Our data support further studies of immune activating therapies in combination with immune checkpoint blockade in the not intrinsically activated cancer types and advocate to combine different genomic and transcriptomic biomarkers (including HRD and TMB) for comprehensive molecular diagnostics and therapy guidance. Citation Format: Jan Budczies, Klaus Kluck, Susanne Beck, Iordanis Ouralidis, Michael Allgäuer, Michael Menzel, Eugen Rempel, Daniel Kazdal, Lukas Perkhofer, Alexander Kleger, Peter Schirmacher, Thomas Seufferlein, Albrecht Stenzinger. HRD is inversely correlated with MSI and identifies immunologically cold tumors in most cancer types [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 810.

Simultaneous degradation of trace antibiotics in water by adsorption and catalytic oxidation induced by N-doped reduced graphene oxide (N-rGO): synergistic mechanism

Aimed at current difficulties in the treatment of trace antibiotics in water, an adsorption-catalytic oxidation system was established by combining persulfate and graphene, which have the dual functions of adsorption and catalysis, for simultaneous enrichment and degradation of trace antibiotics in water. The experimental results showed that over 90% sulfamethoxazole could be degraded by the proposed system. The activation energy of the proposed system was 7.9 kJ mol−1, which was significantly lower than those of typical Co catalysts and some carbon-based catalysts. Synergistic effect analysis revealed that catalytic oxidation was the key degradation kinetic of the proposed system, while adsorption showed a significant enhancement effect. Specifically, a compound with large adsorption capacity tended to be degraded preferably and rapidly. Characterization results indicated that N atoms were doped into the graphene framework, resulting in significant impacts on the activation process of potassium bisulfate by activating the sp2 C system. Quenching and free radical trapping experiments revealed that degradation catalyzed by the proposed system was a non-free radical oxidation reaction dominated by singlet oxygen. In summary, the proposed design was rational, N-rGO surface provided good adsorption and catalysis sites, the synergistic effect of adsorption and catalytic oxidation led to rapid and effective enrichment and in situ degradation of trace antibiotics in water.

Electrodialysis ion-exchange membrane bioreactor (EDIMB) to remove nitrate from water: Optimization of operating conditions and kinetics analysis

Nitrate pollution has become a worldwide problem. In this study, we remove nitrate from water by electrodialysis ion-exchange membrane bioreactor (EDIMB) and enabling simultaneous nitrate enrichment and denitrification. In this reactor, nitrate migrated from the water chamber to the biological chamber via electrodialysis and was degraded by microorganisms. The effects of voltage and biomass concentration on the reactor performance were examined, and the kinetics data of the water chamber and biological chamber were fitted. The experimental results showed that the migration of nitrate in the water chamber conformed to the first-order model, and the constructed zero-Michaelis-Menten model described changes in nitrate concentration in the biological chamber. Furthermore, when the inflow nitrate concentration was 40 mg N/L, 5 V was the best voltage, and 3.00 g VSS/L was the best biomass concentration. The nitrate removal rate in the water chamber was 98.94%, and there was no accumulation of nitrate or nitrite in the biological chamber. Compared with traditional ED processes, the nitrate removal efficiency was 8.86% higher, and the current efficiency was 22.14% higher. The total organic carbon (TOC) of the water chamber was only 1.43 mg C/L, which proves that the structure of the EDIMB confined the denitrifying bacteria and organic carbon donors in the biological chamber and avoided secondary pollution in the water chamber. Microbial community analysis showed that Thauera (66.06%) was the dominant bacterium in the EDIMB system, and Azoarcus (9.81%) was a minor denitrifying genus.

Environmental and Production Aspects of Using Fertilizers Based on Waste Elemental Sulfur and Organic Materials.

Crop fertilization with sulfur is an important part of agricultural practices, as is the systematic increase in soil organic matter content. Materials of waste origin constitute a source of plant-available sulfur, as well as soil organic matter. The study was to verify the hypothesis assuming that combining waste sulfur pulp and its mixtures with organic materials enables simultaneous soil enrichment with readily available sulfur and organic matter. A 240-day incubation experiment was conducted, on two soils: very light and heavy; with two sulfur doses applied to each soil (20 and 40 mg S/kg d.m. for very light soil, and 30 and 60 mg S/kg d.m. for heavy soil). The sulfate sulfur content in the incubated soil material, treated with the addition of sulfur pulp and its mixtures with organic materials, increased significantly up to day 60 and then decreased. The application of these materials significantly increased the content of available sulfur and decreased the pH value of the incubated material. The effect of the introduced materials on dehydrogenase activity depended on soil granulometric composition (the impact of the applied materials on the activity of these enzymes in very light soil was small, and in heavy soil, their activity was usually limited by the presence of introduced materials). Application of the studied materials had little effect on the total organic carbon content in the incubated soil material (a significant change in the value of this parameter, in relation to the control soil, was recorded in some treatments of heavy soil).

A Spin-Tip Enrichment Strategy for Simultaneous Analysis of N-Glycopeptides and Phosphopeptides from Human Pancreatic Tissues.

Mass spectrometry can provide deep coverage of post-translational modifications (PTMs), although enrichment of these modifications from complex biological matrices is often necessary due to their low stoichiometry in comparison to non-modified analytes. Most enrichment workflows of PTMs on peptides in bottom-up proteomics workflows, where proteins are enzymatically digested before the resulting peptides are analyzed, only enrich one type of modification. It is the entire complement of PTMs, however, that leads to biological functions, and enrichment of a single type of PTM may miss such crosstalk of PTMs. PTM crosstalk has been observed between protein glycosylation and phosphorylation, the two most common PTMs in human proteins and also the two most studied PTMs using mass spectrometry workflows. Using the simultaneous enrichment strategy described herein, both PTMs are enriched from post-mortem human pancreatic tissue, a complex biological matrix. Dual-functional Ti(IV)-immobilized metal affinity chromatography is used to separate various forms of glycosylation and phosphorylation simultaneously in multiple fractions in a convenient spin tip-based method, allowing downstream analyses of potential PTM crosstalk interactions. This enrichment workflow for glyco- and phosphopeptides can be applied to various sample types to achieve deep profiling of multiple PTMs and identify potential target molecules for future studies.

L-Cysteine functionalized graphene oxide nanoarchitectonics: A metal-free Hg2+ nanosensor with peroxidase-like activity boosted by competitive adsorption.

Developing non-noble metal, even metal-free chemical sensors for the detection of toxic heavy metal ions is significantly desirable for economically and environmentally sustainable application but has heretofore remained elusive. Herein, a L-cysteine functionalized graphene oxide nanosheet (CGO) nanoarchitectonics, greenly synthesized by a very simple method at room temperature, was utilized to realize the simultaneous enrichment and colorimetric detection of trace mercury ions (Hg2+). It was discovered that CGO, as a nanozyme mimic exhibited greatly enhanced peroxidase-like catalytic activity than the pristine graphene oxide. By exploring the interactions of CGO nanozyme with colorimetric substrate, 3,3',5,5'-tetramethylbenzidine (TMB) and target Hg2+ ions, we found that the sensing principle was based mainly on the competitive adsorption between Hg2+ ions and TMB over CGO. The pre-capture of Hg2+ ions hindered the TMB binding on CGO, resulting in the promoted oxidation of TMB by H2O2 to produce more colored oxidation products, from which the colorimetric sensing of Hg2+ was realized with a good detection effect on 5μgL-1 solution. As an enrichment-sensing integration platform, this metal-free sensor is cost-effective and sensitive, and presents considerable anti-interference ability over other metal ions. Overall, this work not only expands the application of graphene-based materials in colorimetric detection but also provides a general sensing principle to construct highly sensitive sensors.

Simultaneous extraction and enrichment of alkaloids from lotus leaf by in-situ cloud point-reinforced ionic liquid assisted mechanochemical extraction technology

A novel, green and efficient in-situ cloud point-reinforced ionic liquid-assisted mechanochemical extraction (IS-CPR-IL-MCE) technique coupled with ultrahigh performance liquid chromatography was established to simultaneously extract, concentrate and separate five alkaloids (including liensinine, isoliensinine, neferine, O-demethyl nuciferine and nuciferine) from lotus leaf. The parameters affecting the extraction efficiency of target analytes, such as the amount of IL, surfactant and salt, grinding time, pH, enrichment temperature and time were systematically studied and optimized by single-factor and multifactor experiments. The highest extraction yield of alkaloids was obtained by IS-CPR-IL-MCE under the following conditions: 0.23 g of 1-dodecyl-3-methylimidazolium bromide, 0.37 g of Triton X-100, 7.73 of pH, 5 min of milling time, 2.5 g of (NH4)2SO4, 60 ℃ and 20 min of enrichment temperature and time. The developed method exhibited a good linearity in the range of 0.5–100.0 μg/mL with the coefficients of correction more than 0.9992, low limit of detection of 8.0–11.2 ng/mL, acceptable reproducibility below 4.45%, and satisfactory recovery in the range of 80.4–93.7% The results demonstrated that the proposed method was successfully applied to the extraction of alkaloids from lotus leaf.

In Situ Electroporation on PERFECT Filter for High-Efficiency and High-Viability Tumor Cell Labeling.

Labeling-assisted visualization is a powerful strategy to track circulating tumor cells (CTCs) for mechanism study (e.g., tumor metastasis). Due to the rarity of CTCs in the whole blood, efficient simultaneous enrichment and labeling of CTCs are needed. Hereby, novel in situ electroporation on a previously-developed micropore-arrayed filter (PERFECT filter) is proposed. Benefiting from the ultra-small-thickness and high-porosity of the filter plus high precision pore diameter, target rare tumor cells were enriched with less damage and uniform size distribution, contributing to enhanced molecular delivery efficiency and cell viability in the downstream electroporation. Various biomolecules (e.g., small molecule dyes, plasmids, and functional proteins) were used to verify this in situ electroporation system. High labeling efficiency (74.08 ± 2.94%) and high viability (81.15 ± 3.04%, verified via live/dead staining) were achieved by optimizing the parameters of electric field strength and pulse number, ensuring the labeled tumor cells can be used for further culture and down-stream analysis. In addition, high specificity (99.03 ± 1.67%) probing of tumor cells was further achieved by introducing fluorescent dye-conjugated antibodies into target cells. The whole procedure, including cell separation and electroporation, can be finished quickly (<10 min). The proposed in situ electroporation on the PERFECT filter system has great potential to track CTCs for tumor metastasis studies.

Simultaneous enrichment and separation based on ion concentration polarization effect on a paper based analytical device

In this paper, simultaneous enrichment and separation of ions and amphoteric components were successfully demonstrated by using electric field (E) and pH gradient (double gradient) in the ion depletion zone of anion concentration polarization interface established on a paper fluid channel. Experimental results were visualized with colored ions (bright blue and amaranth) and protein probes (phycocyanin and cytochrome C). With optimization, colored phycocyanin and bovine hemoglobin with similar pI as that of albumin and immunoglobulin respectively were well separated in 900 s with 10-fold enrichment effect. Based on the separation and enrichment function of this paper-based analytical device (PAD) and rapid selective staining of human serum albumin (HSA) with bromophenol blue, a rapid colorimetric detection of HSA was implemented with smartphone camera. A limit of detection (LOD) of 5.2 mg·L−1 was achieved in the clinically significant range of 10–300 mg·L−1 (R2 = 0.99). This method was applied to real human urine samples with good agreement (ɑ = 0.01) to clinical detection method (immunoturbidimetry). With the separation and enrichment functions of PAD, both the specificity and sensitivity were enhanced, which provides a solid basis for point-of-care test of microalbuminuria. Therefore, this PAD device is potential for sample pretreatment and detection of target components from complex physiological samples.

Internal oligo(dT) priming introduces systematic bias in bulk and single-cell RNA sequencing count data.

Significant advances in RNA sequencing have been recently made possible by using oligo(dT) primers for simultaneous mRNA enrichment and reverse transcription priming. The associated increase in efficiency has enabled more economical bulk RNA sequencing methods and the advent of high-throughput single-cell RNA sequencing, already one of the most widely adopted methods in transcriptomics. However, the effects of off-target oligo(dT) priming on gene expression quantification have not been appreciated. In the present study, we describe the extent, the possible causes, and the consequences of internal oligo(dT) priming across multiple public datasets obtained from various bulk and single-cell RNA sequencing platforms. To explore and address this issue, we developed a computational algorithm for RNA counting methods, which identifies the sequencing read alignments that likely resulted from internal oligo(dT) priming and removes them from the data. Directly comparing filtered datasets to those obtained by an alternative method reveals significant improvements in gene expression measurement. Finally, we infer a list of human genes whose expression quantification is most likely to be affected by internal oligo(dT) priming and predict that when measured using these methods, the expression of most genes may be inflated by at least 10% whereby some genes are affected more than others.

Nitrogen, oxygen-codoped hierarchically porous biochar for simultaneous enrichment and ultrasensitive determination of o-xylene and its hydroxyl metabolites in human urine by solid phase microextraction-gas chromatography-mass spectrometry

o-Xylene is carcinogenic to human and animals, and the exposure of it could cause serious health problems. The analysis of o-xylene and its hydroxyl metabolites is of great significance for monitoring human exposure and health care. Herein, low-cost waste biomass, bovine bone, has been carbonized to obtain nitrogen and oxygen codoped hierarchically porous biochar (NHPBC) with outstanding advantages, including high specific surface area and sufficient heteroatoms. After systematically investigating enrichment performance of NHPBC towards various organic pollutants, it has been proved that the prepared NHPBC is suitable for high-efficient enrichment of o-xylene and its hydroxyl metabolites. The enrichment factors of NHPBC-coated fiber are from 2384 to 6949, which are 11.1–92.5 times higher than those of commercial solid phase microextraction (SPME) fibers. Under the optimum condition (extraction for 50 min at 50 °C, and desorption at 330 °C for 5 min), an ultrasensitive method with low limits of detection (0.091–1.65 ng L-1), wide linear ranges (5–5000 ng L-1), and good reproducibility (2.19–7.28% for single fiber, n = 5, and 2.64–9.98% for fiber-to-fiber, n = 3) has been developed for simultaneous determination of o-xylene and its hydroxyl metabolites, by coupling NHPBC-coated fiber with gas chromatography-mass spectrometry. This study is expected to benefit for the applications of porous carbon in adsorption, and provide more approaches for the control and precise quantifications of volatile organic compounds (VOCs).

Generic Enrichment of Organic Contaminants in Human Biomonitoring: Application in Monitoring Early Life Exposures to Fipronil via Breast Milk

In human biomonitoring, a high-throughput extraction and enrichment method for multiple types of organic contaminants at the part-per-trillion level is critical yet challenging, especially in the limited sample volume. When large-scale sample analysis is involved, low cost is often what we should consider. We describe a generic and straightforward cold-induced liquid-liquid extraction (CI-LLE) strategy to meet this need. Current methods for extracting and enriching organic contaminants from biological samples often require multistep sample processing, including specially tailoring the extraction solvent or adsorbents. This method uses cold-induced phase separation to achieve the extraction and enrichment of studied organic contaminants by adjusting the proportion of acetonitrile/water mixture, so as to integrate the extraction and enrichment in one step without additional reagents and adsorbents. In this study, fipronil insecticide was used as a representative compound to determine the key parameters of CI-LLE. The optimized CI-LLE procedure allowed simultaneous extraction and enrichment of studied organic contaminants, providing excellent enrichment factors (especially for lipophilic organic contaminants). CI-LLE was further applied in monitoring early life exposures of fipronil in 109 breast milk samples. This study provided baseline data on fipronil levels in breast milk samples from China. For infants, exposure to fipronil is of concern. In summary, CI-LLE provides a feasible solution for a generic, efficient, and low-cost preparation of biological samples and promotes high-throughput batch analysis of organic contaminants for large-scale human biomonitoring.

Simultaneous enrichment of bisphenols and polyfluoroalkyl substances by cyclodextrin-fluorinated covalent organic frameworks membrane in food packaging samples

Efficient separation and preconcentration of trace harmful substances in food samples is a prerequisite for reliable analysis. Most of harmful substances with different properties coexist in the food samples, which is difficult to achieve simultaneously extraction through traditional adsorbents. In this work, a new adsorbent based on cyclodextrin- fluorinated covalent organic frameworks (CD-F-COF) was prepared. The mechanism of the CD-F-COF recognizing polyfluoroalkyl substances (PFASs) and bisphenols (BPs) were validated by molecular simulation. The CD-F-COF showed strong fluorophilic and host-guest interactions for polyfluoroalkyl substances (PFASs) and bisphenols (BPs), respectively. The CD-F-COF coated membranes were immobilized on the syringe filter and coupled with multi-channel syringe pump to achieve high-throughput sample pretreatment. After that, a sensitive analytical method for the simultaneous enrichment and determination of trace BPs and PFASs was established followed by HPLC-MS/MS. The results indicated that the limits of detection for the seven BPs and three PFASs were in the range of 0.006–0.050 ng/g and 0.001–0.008 ng/g. This method has great potential for application in sample preparation as it can fulfill fast and high-throughput for enrichment of trace multiple targets.

Synergistic synthesis of hydrophilic hollow zirconium organic frameworks for simultaneous recognition and capture of phosphorylated and glycosylated peptides

Highly efficient extraction of phospho- and glycopeptides from complicated biological samples is extremely crucial for comprehensive characterization of protein phosphorylation and glycosylation based on mass spectrometry (MS). In this work, a new synergistic strategy that combined surface covalent modification and alkaline etching was developed to synthesize hydrophilic hollow zirconium-organic frameworks (HHZr-MOFs) for simultaneous recognition and capture of phospho- and N-glycopeptides. The unique properties including high specific surface area, mesoporous shell and hollow cavity endowed HHZr-MOFs with facilitated mass transport and abundant accessible active sites. Benefited from the maltose modified on the external surface and Zr–O clusters retained on the internal surface, HHZr-MOFs could act as a highly efficient bifunctional probe for simultaneous enrichment of phospho- and N-glycopeptides based on hydrophilic interaction chromatography (HILIC) and metal oxide affinity chromatography (MOAC), respectively. Finally, a total of 98 endogenous phosphopeptides and 216 endogenous N-glycopeptides were simultaneously captured by HHZr-MOFs from saliva samples of patients with oral inflammation, and several phospho- and glycoproteins related with coagulation, bacterial defense and immune response for oral inflammation were identified by Gene ontology (GO) analyses, confirming the great potential of HHZr-MOFs in rapid detection of clinical biomarkers and comprehensive profiling of phosphoproteomic and glycoproteomic for complex biological samples. This work not only provides an alternative method to precisely design and synthesize sophisticated hollow MOFs with multifunctionalities, but also offers a novel concept of multifunctional material design for bioseparation and analysis in modification-specific proteomics.

Amino-functional metal–organic framework as a general applicable adsorbent for simultaneous enrichment of nine neonicotinoids

Four functional metal–organic frameworks (MOFs) were facilely synthesized through one-pot procedure or post-synthetic modification method and used as adsorbents for simultaneous enrichment of nine neonicotinoids (NEOs) for the first time. Of which, amino-functional MIL-101-NH2 showed general high affinity towards nine NEOs and performed the best due to extraordinarily high surface area and specific interaction with analytes. A simple, efficient and robust method was developed by dispersive solid phase extraction with MIL-101-NH2 combining with liquid chromatography mass spectrometry (dSPE-LC-MS). Key factors that affecting enrichment efficiency were investigated and the established method demonstrated high sensitivity with detection limits as low as 0.02–0.1 ng/mL and wide linearity range over 3–4 orders of magnitude. Besides, compared with commercial SPE cartridges, this adsorbent showed superior enrichment efficiency and could be used for at least five times without obvious recovery decrease. The method was also applied for determination of trace NEOs in aqueous environmental samples and NEO contamination was found. This study demonstrated the practicability of facile synthetic MOF in simultaneous enrichment of nine NEOs and offered a simple and general method for trace amount NEOs sample preparation in real samples.

A novel graphene oxide/chitosan foam incorporated with metal-organic framework stationary phase for simultaneous enrichment of glycopeptide and phosphopeptide with high efficiency.

A novel hydrophilic porous biocomposite was fabricated by incorporating graphene oxide (GO) @chitosan (CS) foam substrate (GO@CS@ZIF-8 foam) with ZIF-8 crystals in situ via a facile stirring method for simultaneous enrichment of glycopeptides and phosphopeptides from complex biological samples. The experimental results demonstrated that GO@CS@ZIF-8 foam exhibited favorable specificity for simultaneous enrichment of N-glycopeptides and phosphopeptides under the same condition for HRP and β-casein tryptic digest mixtures. The novel material was further applied to enriching both glycopeptides and phosphopeptides simultaneously from 4 μL complex human serum, and 423N-glycopeptides and 40 phosphopeptides corresponding to 133 glycoproteins and 29 phosphoproteins were identified, respectively.