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Ferroptosis is a non-apoptotic regulated cell death caused by iron accumulation and subsequent lipid peroxidation. Currently, the therapeutic role of ferroptosis on cancer is gaining increasing interest. Baicalin an active component in Scutellaria baicalensis Georgi with anticancer potential various cancer types; however, the effects of baicalein on bladder cancer and the underlying molecular mechanisms remain largely unknown. In the study, we investigated the effect of baicalin on bladder cancer cells 5637 and KU-19-19. As a result, we show baicalin exerted its anticancer activity by inducing apoptosis and cell death in bladder cancer cells. Subsequently, we for the first time demonstrate baicalin-induced ferroptotic cell death in vitro and in vivo, accompanied by reactive oxygen species (ROS) accumulation and intracellular chelate iron enrichment. The ferroptosis inhibitor deferoxamine but not necrostatin-1, chloroquine (CQ), N-acetyl-l-cysteine, l-glutathione reduced, or carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]-fluoromethylketone (Z-VAD-FMK) rescued baicalin-induced cell death, indicating ferroptosis contributed to baicalin-induced cell death. Mechanistically, we show that ferritin heavy chain 1 (FTH1) was a key determinant for baicalin-induced ferroptosis. Overexpression of FTH1 abrogated the anticancer effects of baicalin in both 5637 and KU19-19 cells. Taken together, our data for the first time suggest that the natural product baicalin exerts its anticancer activity by inducing FTH1-dependent ferroptosis, which will hopefully provide a prospective compound for bladder cancer treatment., Graphical abstract Baicalin exerts its anticancer activity in bladder cancer by inducing ferritin heavy chain 1 (FTH1)-dependent ferroptosis, which will hopefully provide great therapeutic potential for bladder cancer treatment.Image 1

Natural product (NP) has a long history in promoting modern drug discovery, which has derived or inspired a large number of currently prescribed drugs. Recently, the NPs have emerged as the ideal candidates to combine with other therapeutic strategies to deal with the persistent challenge of conventional therapy, and the molecular regulation mechanism underlying these combinations is crucial for the related communities. Thus, it is urgently demanded to comprehensively provide the disease-specific molecular regulation data for various NP-based drug combinations. However, no database has been developed yet to describe such valuable information. In this study, a newly developed database entitled ‘Natural Product-based Drug Combination and Its Disease-specific Molecular Regulation (NPCDR)’ was thus introduced. This database was unique in (a) providing the comprehensive information of NP-based drug combinations & describing their clinically or experimentally validated therapeutic effect, (b) giving the disease-specific molecular regulation data for a number of NP-based drug combinations, (c) fully referencing all NPs, drugs, regulated molecules/pathways by cross-linking them to the available databases describing their biological or pharmaceutical characteristics. Therefore, NPCDR is expected to have great implications for the future practice of network pharmacology, medical biochemistry, drug design, and medicinal chemistry. This database is now freely accessible without any login requirement at both official (https://idrblab.org/npcdr/) and mirror (http://npcdr.idrblab.net/) sites., Graphical Abstract Graphical AbstractNPCDR: natural product-based drug combination and its disease-specific molecular regulation.

A series of hierarchical CoAPO-5 molecular sieves was hydrothermally synthesized using cetyltrimethylammonium bromide (CTAB) as the template. The structural properties of CoAPO-5 molecular sieves with different amount of CTAB, including AFI-0.10, AFI-0.25, AFI-0.35, AFI-0.45 and AFI-0.55 were all characterized by XRD, SEM, N2 adsorption-desorption and NH3-TPD. The catalytic performance of as-prepared CoAPO-5 molecular sieves for the oxidation of furfural to maleic acid was investigated. Research results indicated that the structure characteristics as well as the catalytic performances of CoAPO-5 molecular sieves were strongly affected by CTAB amount. Among those hierarchical CoAPO-5 catalysts, AFI-0.45 sample exhibited highest maleic acid yield of 85.9% at 60℃ after 3 h reaction. In addition, the stability of AFI-0.45 was proved persistent for subsequent cycles.

A novel composite nonwoven material, activated carbon fiber enhanced microfibrous entrapped sorbent (ACF-MFES), has been successfully prepared via the wet-laid and sintering process. Effects of fiber and particle sizes on the bed pressure drop of various filter media were studied. The performances of different filters were studied by breakthrough experiments. Results showed the adsorption rate constant of ACF-MFES was 10 times greater than that of the packed bed. And the ACF-MFES demonstrated highest adsorptive capacity. Finally, ACF-MFES was combined with the packed bed to develop a composite system. The filter’s adsorptive capacity of the three-layer composite bed with ACF-MFES as a polishing layer increased by 330%, compared with the sorbent packed bed.

CoAPO-5 molecular sieves were synthesized by a novel dynamic method. Crystallization, morphology and surface acidity were investigated by XRD, SEM, and Py-IR in details, and compared with samples prepared by traditional static method. Synthesis conditions, reaction time, temperature and the amount of catalyst were optimized as important parameters. The desulfurization performance of CoAPO-5 catalysts synthesized by two different methods was evaluated and compared. Also, some experiments were carried out to test selectivity and regenerability of CoAPO-5 catalysts synthesized by the dynamic method. Finally, ODS reaction kinetics and mechanism using CoAPO-5 was studied and discussed. Results indicated that dynamic method greatly shortened crystallization time, while kept the same structure and sulfur removal capacity of CoAPO-5. The dynamic synthesis method could be considered as an alternative method to prepare porous molecular sieves.

Curcumenol, an effective ingredient of Wenyujin, has been reported that exerted its antitumor potential in a few cancer types. However, the effect and molecular mechanism of curcumenol in lung cancer are largely unknown. Here, we found that curcumenol induced cell death and suppressed cell proliferation in lung cancer cells. Next, we demonstrated that ferroptosis was the predominant method that contributed to curcumenol-induced cell death of lung cancer in vitro and vivo for the first time. Subsequently, using RNA sequencing, we found that the long non-coding RNA H19 (lncRNA H19) was significantly downregulated in lung cancer cells treated with curcumenol, when compared to untreated controls. Overexpression of lncRNA H19 eliminated the anticancer effect of curcumenol, while lncRNA H19 knockdown promoted ferroptosis induced by curcumenol treatment. Mechanistically, we showed that lncRNA H19 functioned as a competing endogenous RNA to bind to miR-19b-3p, thereby enhanced the transcription activity of its endogenous target, ferritin heavy chain 1 (FTH1), a marker of ferroptosis. In conclusion, our data show that the natural product curcumenol exerted its antitumor effects on lung cancer by triggering ferroptosis, and the lncRNA H19/miR-19b-3p/FTH1 axis plays an essential role in curcumenol-induced ferroptotic cell death. Therefore, our findings will hopefully provide a valuable drug for treating lung cancer patients.

Glutathione is an essential intra- and extracellular antioxidant. The level of glutathione in the body is highly related to different disease states and is a useful indicator of disease risk and oxidative stress status. We have developed a sensitive, selective, and comprehensive LC-MS/MS method for the absolute quantification and 13C-tracer analysis of total glutathione using dithiothreitol for the reduction of glutathione disulfide. The limit of detection (LOD) was 0.01 μM, while the lower limit of quantification (LLOQ) was 0.78 μM, with the linear (R = 0.9997) range extending up to 100 μM. The intra-run and inter-run coefficients of variation of 2.49% and 2.04%, respectively, attest to high repeatability. Mean (±SD) recoveries of three different concentrations (low, medium, high) of GSH spiked into aliquots of HCT116 cells prior to cell extraction were 108.9% (±2.1), 100.8% (±8.3), and 99.9% (±7.1), respectively. Finally, using a 20 Da wide Q1 window in MRM mode, we were able to detect and relatively quantify all isotopic labeling states of GSH extracted from HCT116 cells fed with either 13C-labeled glucose or glutamine.

UV pretreatment has proven effective in enhancing the sulfur heterocycle specificity and saturation capacity of TiO2 adsorbents. Previous efforts in our laboratory have shown this effect to persist for over two weeks and were attributed to increased densities of surface hydroxyl groups as assessed by XPS and FTIR evaluations. This paper presents further evidence of the previous assertion by tracking the UV-induced conversion of adsorbed water and lattice oxygen into surface hydroxyls as monitored by XPS. Two different commercial TiO2 adsorbents (@ 163 and 70 m2/g) were investigated at various hydration levels as determined by TGA. Deconvolution of the XPS spectra demonstrated both the qualitative nature and quantitative conversion of adsorbed water and lattice oxygen according to the following stoichiometry, where one lattice oxygen is converted into two surface hydroxyls. O (lattice) 2 - + H 2 O (ads) → UV 2OH - Eight different reaction cases were examined using the 163 and 70 m2/g supports at four different hydration levels each. The measured stoichiometry for the above-noted conversion varied from 1.83 to 2.15 with an average value of 1.98 and a standard deviation of 0.10. Samples removed from the XPS chamber and stored in laboratory conditions showed that photo-generated surface hydroxyls could persist for over two weeks with or without handling.

Isobaric vapour–liquid equilibrium (VLE) data for two binary systems of p-Cresol (PC) + diethanolamine (DEA) and m-Cresol (MC) + DEA were measured at 20.0 kPa. The Herington area method was used to check the binary VLE data, and the results showed good thermodynamic consistency. Meanwhile, the Wilson, NRTL, UNIQUAC models and the chemistry theory proposed by Dolezalek were used to correlate the VLE data. The binary energy interaction parameters for activity models, and reaction equilibrium constants for chemistry theory were obtained. With help of the parameters obtained in this work, the NRTL model was used to predict the VLE data of the two binary systems at the pressure of 8.33 kPa. The predictive results were compared with the literature’s data. At same time, the excess Gibbs free energy for the two binary systems, and infinite dilution activity coefficients for MC and PC in DEA were estimated. The calculated results showed that the DEA had slightly stronger interaction with PC than MC.

Glutathione (GSH) and glutathione disulfide (GSSG) are commonly used to assess the oxidative status of a biological system. Various protocols are available for the analysis of GSH and GSSG in biomedical specimens. In this study, we present an optimized protocol for the in situ derivatization of GSH with N-ethylmaleimide (NEM) to prevent GSH autooxidation, and thus to preserve the GSH/GSSG ratio during sample preparation. The protocol comprises the incubation of cells in NEM containing phosphate buffered saline (PBS), followed by metabolite extraction with 80% methanol. Further, to preserve the use of QTOF-MS, which may lack the linear dynamic range required for the simultaneous quantification of GSH and GSSG in non-targeted metabolomics, we combined liquid chromatographic separation with the online monitoring of UV absorbance of GS-NEM at 210 nm and the detection of GSSG and its corresponding stable isotope-labeled internal standard by QTOF-MS operated with a 10 Da Q1 window. The limit of detection (LOD) for GS-NEM was 7.81 &micro, M and the linear range extended from 15.63 &micro, M to 1000 &micro, M with a squared correlation coefficient R2 of 0.9997. The LOD for GSSG was 0.001 &micro, M, and the lower limit of quantification (LLOQ) was 0.01 &micro, M, with the linear (R2 = 0.9994) range extending up to 10 &micro, M. The method showed high repeatability with intra-run and inter-run coefficients of variation of 3.48% and 2.51% for GS-NEM, and 3.11% and 3.66% for GSSG, respectively. Mean recoveries of three different spike-in levels (low, medium, high) of GSSG and GS-NEM were above 92%. Finally, the method was applied to the determination of changes in the GSH/GSSG ratio either in response to oxidative stress in cells lacking one or both monocarboxylate transporters MCT1 and MCT4, or in adaptation to the NADPH (nicotinamide adenine dinucleotide phosphate) consuming production of D-2-hydroxyglutarate in cells carrying mutations in the isocitrate dehydrogenase genes IDH1 and IDH2.

Measurements of isobaric vapor–liquid equilibrium (VLE) results for binary systems of m-cresol (MC) + diisopropanolamine (DIPA) and 2,6-dimethylphenol (DMP) + DIPA and the ternary system of MC + DMP + DIPA were conducted at the pressure of 20.0 kPa. The binary VLE experimental data showed that DIPA had stronger interaction with MC than DMP. The ternary system experimental VLE data showed that DIPA could improve the relative volatility of DMP to MC. The binary experimental data were checked by using Herington area and point test methods, and the checked results were thermodynamically consistent. Meanwhile, the VLE data were correlated by Wilson, nonrandom two-liquid, and universal quasichemical models, and the binary energy interaction parameters for these models were obtained. These activity coefficient models were used to predict the ternary system VLE data. The predictive results suggested that the Wilson model had the best prediction.

A series of metal-containing silicoaluminophosphate (MeSAPOs) molecular sieves was synthesized by the hydrothermal method, where bauxite was used as the source for single Si, Al and Me (Me = Fe, Ti). The products with different compositions, including MeSAPO-5, MeSAPO-11, MeSAPO-34 and MeSAPO-44, were all characterized by XRD, SEM, UV–vis and NH 3 -TPD. The catalytic performance of those MeSAPOs for dehydration of fructose to 5-hydroxymethylfurfural (HMF) were investigated. The results indicated that the catalytic performance decreased in the order of MeSAPO-11 > MeSAPO-5 > MeSAPO-34 > MeSAPO-44, which corresponded to the order of the total number of the acid sites. Among those MeSAPOs molecular sieves, MeSAPO-11 had the highest HMF yield of 65.1% at 170 °C after 2.5 h, due to more acid sites. Research results also indicated that the dehydration reaction rate and HMF yield were related to the acidity.

Isobaric vapour–liquid equilibrium (VLE) data for binary systems containing o-cresol (OC) + m-cresol (MC), OC + 2, 6-dimethylphenol (DMP), and MC + DMP at 20.0 kPa were measured by using a modified Othmer still. Its reliability was confirmed by measuring the saturated vapour pressure data for the components of MC and DMP. Herington area test was used to confirm the thermodynamic consistency for these binary systems, and the results showed good thermodynamic consistency. The binary VLE experimental data were correlated and predicted by Wilson, NRTL, and UNIFAC models. The results correlated by Wilson and NRTL models agree well with the experimental values. The results predicted by UNIFAC are in accordance with experimental data with rational deviations for systems OC + MC and OC + DMP but show relatively large deviations between the predicted values and experimental data for MC + DMP system. By defining the group =COH in DMP and MC as two different groups, the experimental data were correlated, and new groups with binary interaction parameters were obtained. The results calculated by UNIFAC with new defining groups are in accordance with the experimental data.

Metal ions differed greatly in affinity towards phosphopeptides, and thus it is essential to systematically compare the phosphopeptides enrichment ability of different metal ions usually used in the IMAC techniques. In this work, for the first time, eight metal ions, including Nb5+, Ti4+, Zr4+, Ga3+, Y3+, In3+, Ce4+, Fe3+, were immobilized on the polydopamine (PDA)-coated Fe3O4 (denoted as Fe3O4@PDA-Mn+), and systematically compared by the real biosamples, in addition to standard phosphopeptides. Fe3O4 microspheres were synthesized via the solvothermal reaction, followed by self-polymerization of dopamine on the surface. Then through taking advantage of the hydroxyl and amino group of PDA, the eight metal ions were easily adhered to the surface of Fe3O4@PDA. After characterization, the resultant Fe3O4@PDA-Mn+ microspheres were applied to phosphopeptides enrichment based on the binding affinity between metal ions and phosphopeptides. According to the results, different metal ions presented diverse phosphopeptides enrichment efficiency in terms of selectivity, sensitivity and the enrichment ability from real complex samples, and Fe3O4@PDA-Nb5+ and Fe3O4@PDA-Ti4+ showed obvious advantages of the phosphopeptides enrichment effect after the comparison. This systematic comparison may provide certain reference for the use and development of IMAC materials in the future.

This paper explores the transient photocatalytic oxidation mechanism of carbon contaminants from a high surface area anatase TiO2 pellet under starved water/oxygen reaction conditions created when specimens are irradiated via a 375 nm UV laser inside the UHV analysis chamber of an XPS spectrometer. Complementary results are also provided following similar UV irradiations and reaction procedures in an evacuated in situ reaction cell of a Fourier-transform infrared spectrometer (FTIR). An interactive and non-steady state transient photocatalytic reaction is observed between surface carbon species and strongly adsorbed H2O brought to the exterior surface of the pellet via UV photodesorption from within the deeper lying pores of the pellet. The reaction stoichiometry and quantum efficiency of the reaction are reported at various irradiation intensities. In situ FTIR spectral features are also presented and discussed for a non-UV treated TiO2 sample and a 2-hour UV-treated TiO2 sample under evacuated conditions also showing the decomposition of carbon contaminants species and the consumption of adsorbed water/hydroxyls with the ensuing formation of carboxyl (HO-C O) carbon species and isolated surface hydroxyls. The photocatalytic decomposition of carbon species and the concomitant consumption of oxygen containing species was also tracked by following the XPS spectral changes of a UV-irradiated area on the pellet surface compared to a dark reference spot on the same specimen. Eight different reaction cases at four different UV intensities, repeated twice each, were also investigated using separate pieces of the same TiO2 media. The measured stoichiometry for the decomposition of carbon species and consumption of oxygen ranged from 0.53 during the first 10–20 min of irradiation and increased to 0.65 with an average value of 0.59 and a standard deviation of 0.11. These data suggest that the reaction product and leaving group from the TiO2 surface is primarily CO2 during the first 10–20 min of initial reaction with perhaps a small fraction of CO toward the end of reaction. Heating the sample specimen to 100 °C for 2-hour inside the XPS-UHV analysis chamber prior to UV illumination was effective in eliminating photocatalytic oxidation and carbon removal from the surface thereby demonstrating that strongly adsorbed water (prior to heating in vacuum) was a critical and limiting reagent in the overall H2O transport and reaction process. Photon efficiencies for the reaction were calculated based on the number of carbon species removed from the XPS-observable surface versus the number of the UV photons adsorbed in the topmost 2 nm of the sample. The highest photon efficiency observed was 0.0186 after 5–10 min of UV exposure at 1.5 mW/cm2. All reaction cases showed a significant efficiency drop after 30 min of UV irradiation due to the consumption of the adsorbed reactants, both carbon and water. From detailed deconvolution of the XPS C 1s spectra, UV irradiation showed a high selectivity towards hydrocarbon contaminant decomposition, which was 75% ± 5% of all carbon species removed.

In this paper, a facile extraction strategy is reported for the analysis of isopentenyl pyrophosphate, a key isoprenoid, based on magnetic core-shell microspheres with Ti4+ ion exterior walls coupled with liquid chromatography and tandem mass spectrometry. Because of their excellent hydrophilicity and biological compatibility, the polydopamine@Fe3 O4 -Ti4+ microspheres display ideal isopentenyl pyrophosphate extraction efficiency. The technique includes three steps: sample loading, nonphosphate washing, and phosphate elution. Moreover, the microspheres can be regenerated by thorough washing with a specific solvent and can be reused multiple times. The liquid chromatography with tandem mass spectrometry separation was performed on a Welch Ultimate® XB-C18 column with a total chromatographic analysis time of 5 min; the analytical recovery was 98.52%. The proposed method was used to determine the isopentenyl pyrophosphate concentration in rat plasma samples collected from the Shanghai Chest Hospital. The results indicate the prospective value of the as-made microspheres for the sensitive and selective enrichment of phosphate compounds in complicated matrices.

Adsorptive desulfurization (ADS) of hydrocarbon fuels at ambient pressure over TiO 2 adsorbents following an ex-situ one-time UV-treatment have been investigated in this work. Based on our previous study, TiO 2 adsorbent showed high adsorptive capacity (5.63 mg S/g adsorbent) when UV-treatment was applied in-situ during the adsorption step. In the current study, Ultra-violet (λ = 365 nm) treatment at 2.0 mW/cm 2 was applied before the breakthrough experiment. And, research results indicate that one-time ex-situ UV-treatment before sulfur adsorption also increased the desulfurization breakthrough capacity of TiO 2 by ca. 50%, from 3.90 mg S/g adsorbent to 5.95 mg S/g adsorbent. Moreover, for multiple adsorption, desorption and regeneration/calcination cycles (at 450 °C in air for 120 min), the stability of the UV-enhanced sulfur adsorption sites (once created) was persistent for subsequent cycles. In-situ IR and XPS were employed to investigate the effect of ex-situ UV treatment on the TiO 2 adsorbent. Based on these IR and XPS results, the photo-enhanced desulfurization capacity of TiO 2 was attributed to an increase in the total number of terminal acidic Ti(IV) OH groups.

Macrophages (Mφ) are abundantly present in the tumor microenvironment and may predict outcome in solid tumors and defined lymphoma subtypes. Mφ heterogeneity, the mechanisms of their recruitment, and their differentiation into lymphoma‐promoting, alternatively activated M2‐like phenotypes are still not fully understood. Therefore, further functional studies are required to understand biological mechanisms associated with human tumor‐associated Mφ (TAM). Here, we show that the global mRNA expression and protein abundance of human Mφ differentiated in Hodgkin lymphoma (HL)‐conditioned medium (CM) differ from those of Mφ educated by conditioned media from diffuse large B‐cell lymphoma (DLBCL) cells or, classically, by macrophage colony‐stimulating factor (M‐CSF). Conditioned media from HL cells support TAM differentiation through upregulation of surface antigens such as CD40, CD163, CD206, and PD‐L1. In particular, RNA and cell surface protein expression of mannose receptor 1 (MRC1)/CD206 significantly exceed the levels induced by classical M‐CSF stimulation in M2‐like Mφ; this is regulated by interleukin 13 to a large extent. Functionally, high CD206 enhances mannose‐dependent endocytosis and uptake of type I collagen. Together with high matrix metalloprotease9 secretion, HL‐TAMs appear to be active modulators of the tumor matrix. Preclinical in ovo models show that co‐cultures of HL cells with monocytes or Mφ support dissemination of lymphoma cells via lymphatic vessels, while tumor size and vessel destruction are decreased in comparison with lymphoma‐only tumors. Immunohistology of human HL tissues reveals a fraction of cases feature large numbers of CD206‐positive cells, with high MRC1 expression being characteristic of HL‐stage IV. In summary, the lymphoma‐TAM interaction contributes to matrix‐remodeling and lymphoma cell dissemination., The study highlights the ability of Hodgkin lymphoma cells to attract and to differentiate monocytes into M2‐like Mφ and the role of IL13 in regulating CD206 but also that CD206 contributes to the remodeling of the tumor microenvironment via take up glycoconjugates as well as type‐I collagen and immunosuppression by PD‐L1 upregulation.

Glutathione is an essential intra- and extracellular antioxidant. The level of glutathione in the body is highly related to different disease states and is a useful indicator of disease risk and oxidative stress status. We have developed a sensitive, selective, and comprehensive LC-MS/MS method for the absolute quantification and

More than half of all brain metastases show infiltrating rather than displacing growth at the macro-metastasis/brain parenchyma interface (MMPI), a finding associated with shorter survival. The Lymphoid Enhancer-binding Factor-1 (LEF1) is an epithelial-mesenchymal transition (EMT) transcription factor that is commonly overexpressed in brain-colonizing cancer cells. Here, we overexpressed LEF1 in an in vivo breast cancer brain colonization model. It shortened survival, albeit without engaging EMT at the MMPI. By differential proteome analysis, we identified a novel function of LEF1 as a regulator of the glutathione (GSH) system, the principal cellular redox buffer. LEF1 overexpression also conferred resistance against therapeutic GSH depletion during brain colonization and improved management of intracellular ROS. We conclude that besides EMT, LEF1 facilitates metastasis by improving the anti-oxidative capacity of epithelial breast cancer cells, in particular during colonization of the brain parenchyma. This article is protected by copyright. All rights reserved.

Photo-assisted adsorptive desulfurization (ADS) of hydrocarbon fuels using TiO2 and Ag/TiO2 adsorbents under mild conditions has been investigated. UV irradiation (λ = 365 nm) was directly introduced into the adsorbent packed bed. Typical UV flux at 1 cm from the UV lamp was 1.8–2.0 mW/cm2. Sulfur removal performance was evaluated by breakthrough experiments in the presence of UV and H2O. Results indicated that the sulfur removal capacity of TiO2 was increased by 50% during UV-assisted ADS. Ag/TiO2 adsorbents showed the highest UV-assisted capacity which was 6.35 mg S/g adsorbent using a model fuel containing 3500 ppmw sulfur (benzothiophene in n-octane) and 1000 ppmw H2O. In situ IR analysis were applied to study the effects of H2O and UV molecules on surface OH groups. The chemical state change of Ag caused by UV irradiation was characterized by X-ray Photoelectron Spectrometer (XPS). Based on IR data, the enhanced desulfurization capacity of TiO2 under UV irradiation was attributed to the increase in the total number of terminal Ti(IV) OH groups. Multi-cycle experiments will be carried out later to study the stability of UV-activated sulfur removal sites and the photo-assisted sulfur removal mechanism will be investigated in the future.

In this work, for the first time, magnetic binary metal oxides nanocomposites which integrated Zr and Ti into one entity on an atomic scale on polydopamine coated magnetic graphene (magG/PD/(Zr-Ti)O4 ) was designed and synthesized, and applied to the enrichment of phosphopeptides. The newly prepared magG/PD/(Zr-Ti)O4 composites gathered the advantages of large surface area, superparamagnetism, biocompatibility and the enhanced affinity properties to phosphopeptides. MagG/PD/ZrO2 , magG/PD/TiO2 , as well as the simple physical mixture of them were introduced to compare with magG/PD/(Zr-Ti)O4 composites. High sensitivity (1 pg/μL or 4.0 × 10(-11) M) and selectivity (weight ratio of β-casein and BSA reached up to 1:8000) toward phosphopeptides were also presented for magG/PD/(Zr-Ti)O4 composites. Additionally, mouse brain tissue was chose as the real samples to further investigate the phosphopeptides enrichment ability of this new material.

Magnetic microspheres (Fe3O4) were coated with polydopamine (PDA) and loaded with the metal ions Ti(IV) and Nb(V) to give a material of type Fe3O4@PDA-Ti/Nb. It is shown to be useful for affinity chromatography and for enrichment of phosphopeptides from both standard protein solutions and real samples. For comparison, such microspheres loaded with single metal ions only (Fe3O4@PDA-Ti and Fe3O4@PDA-Nb) and their physical mixtures were also investigated under identical conditions. The binary metal ion-loaded magnetic microspheres display better enrichment efficiency than the single metal ion-loaded microspheres and their physical mixture. Both multiphosphopeptides and monophosphopeptides can be extracted. The Fe3O4@PDA-Ti/Nb microspheres exhibit ultra-high sensitivity (the lowest detection amount being 2 fmol) and selectivity at a low mass ratio such as in case of β-casein/BSA (1:1000).

Three-layer structure graphene/mesoporous silica composites incorporated with C8-modified interior pore-walls (graphene@mSiO 2 -C8) were prepared and applied for efficient extraction of glucocorticoid residuals in milk followed by liquid chromatography-tandem mass spectrometry (LC–MS/MS) analysis. The graphene@mSiO 2 -C8 nanocomposites were synthesized by coating C8-modified mesoporous silica onto hydrophilic graphene nanosheets through a simple surfactant-mediated co-condensation sol–gel process. The obtained nanosheets possess unique properties of large surface area (632 m 2 /g), extended plate-like morphology in the exterior surface, highly open pore structure with uniform pore size (2.8 nm), numerous C8-modified interior pore-walls, as well as good water dispersibility. The performance of the prepared graphene@mSiO 2 -C8 materials for extracting small hydrophobic molecules directly from complex protein-rich samples was evaluated by analysis of glucocorticoids in milk. Extraction conditions such as sorbents amount, type and volume of eluting solvent, time of adsorption and desorption were investigated and optimized to achieve the best efficiency. Method validations including linearity, recovery, repeatability, and limit of detection (LOD) were also studied. The results indicated that this methodology provided low LOD (S/N = 3, 0.0075–0.03 ng mL −1 ) and good linearity (0.03–60 ng mL −1 , R 2 > 0.996) for glucocorticoids. Satisfactory reusability and stability were also obtained during the extraction. Finally, the graphene@mSiO 2 -C8 composites were successfully applied to the extraction and residue analysis of glucocorticoids in real milk samples. The experimental results showed that this novel approach offered an attractive choice for convenient, efficient and rapid solid-phase extraction of targeted hydrophobic compounds in biological samples.

Rapid and selective enrichment of phosphopeptides from complex biological samples is essential and challenging in phosphorylated proteomics. In this work, for the first time, niobium ions were directly immobilized on the surface of polydopamine-coated magnetic microspheres through a facile and effective synthetic route. The Fe3O4@polydopamine-Nb(5+) (denoted as Fe3O4@PD-Nb(5+)) microspheres possess merits of high hydrophilicity and good biological compatibility, and demonstrated low limit of detection (2 fmol). The selectivity was also basically satisfactory (β-casein:BSA=1:500) to capture phosphopeptides. They were also successfully applied for enrichment of phosphopeptides from real biological samples such as human serum and nonfat milk. Compared with Fe3O4@PD-Ti(4+) microspheres, the Fe3O4@PD-Nb(5+) microspheres exhibit superior selectivity to multi-phosphorylated peptides, and thus may be complementary to the conventional IMAC materials.

Metal ions differed greatly in affinity towards phosphopeptides, and thus it is essential to systematically compare the phosphopeptides enrichment ability of different metal ions usually used in the IMAC techniques. In this work, for the first time, eight metal ions, including Nb

We report herein an extraction method for the analysis of perfluorinated compounds in human serum based on magnetic core–mesoporous shell microspheres with decyl-perfluorinated interior pore-walls (Fe 3 O 4 @mSiO 2 -F 17 ). Thanks to the unique properties of the Fe 3 O 4 @mSiO 2 -F 17 microspheres, macromolecules like proteins could be easily excluded from the mesoporous channels due to size exclusion effect, and perfluorinated compounds (PFCs) in protein-rich biosamples such as serum could thus be directly extracted with the fluorocarbon modified on the channel wall without any other pretreatment procedure. The PFCs adsorbed Fe 3 O 4 @mSiO 2 -F 17 microspheres could then be simply and rapidly isolated by using a magnet, followed by being identified and quantified by LC–MS/MS (high-performance liquid chromatography coupled to tandem mass spectrometry). Five perfluorinatedcarboxylic acids (C6, C8–C11) and perfluorooctane sulfonate (PFOS) were selected as model analytes. In order to achieve the best extraction efficiency, some important factors including the amount of Fe 3 O 4 @mSiO 2 -F 17 microspheres added, adsorption time, type of elution solvent, eluting solvent volume and elution time were investigated. The ranges of the LOD were 0.02–0.05 ng mL −1 for the six PFCs. The recovery of the optimized method varies from 83.13% to 92.42% for human serum samples.

Ag–TiO2 adsorbents have pronounced capacity for selective removal of organosulfur compounds from complex fuel mixtures. Computational calculations were performed to investigate the nature of this pronounced selectivity as well as to study the adsorbent structure. A cluster model was developed for this study. Geometry optimization, frequency analysis, and single-point energy calculations were carried out using density functional theory (B3LYP/6-31G(d)(ECP=SDD(Ag,Ti))//B3LYP/LANL2DZ). The computed adsorption energies included dispersion terms (GD3) and were corrected for basis set superposition errors (BSSEs). Silver incorporated onto anatase–TiO2 clusters and with greater preference in the presence of −OH groups. Adsorption energies were calculated for sulfur-containing species (thiophene, benzothiophene, dibenzothiophene, 4,6-dimethyldibenzothiophene) and nonsulfur aromatics (quinoline, benzofuran, naphthalene, benzene) typically present in fuel mixtures. Calculated adsorption energies are consistent with...

In this work, a facile route was initially developed for preparation of a novel metal oxide affinity chromatography (MOAC) material by grafting titania nanoparticles on polydopamine (PD)-coated graphene (denoted as G@PD@TiO2). In the first step, self-assemble polymerization of dopamine on graphene was performed in basic solution at room temperature, which not only offered the coupling linker between titania and graphene but also improved the hydrophilicity and biological compatibility of the nanohybrids. Thereafter, the titania nanoparticles were grafted on the surface of the PD-coated graphene via a simple hydrothermal treatment. The as-prepared G@PD@TiO2 nanohybrids exhibited high sensitivity (detection limit of 5 fmol) and high selectivity for phosphopeptides at a low molar ratio of phosphopeptides/nonphosphopeptides (1:1000). Moreover, the as-prepared nanohybrids were also investigated for enrichment of phosphopeptides from real biological samples (human serum and mouse brain). A total number of 556 phosphorylation sites were identified from the digest of mouse brain proteins, showing great potential in the practical application.