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Actinide complexes, which could enable the electrocatalytic H

The performance of data-independent acquisition (DIA) mass spectrometry (MS) depends on the separation efficiency of peptide precursors. In Orbitrap-based mass spectrometers, separation efficiency of peptide precursors is limited by the relatively slow scanning rate compared to time of flight (TOF)-based MS. Here, we present PulseDIA, a multi-injection gas-phase fractionation (GPF) strategy for enhanced DIA-MS. This is achieved by equally dividing the conventional DIA analysis covering the entire mass range into multiple injections for DIA analyses with complementary windows. Using mouse liver digests, the PulseDIA method identified up to 50% more peptides and 29% more protein groups than that by conventional DIA with the same length of effective gradient time. Compared to conventional multi-injection GPF, PusleDIA exhibited higher flexibility and identified up to 18% more peptides and 8% more protein groups using two injections. The gain of peptides per effective time unit was the highest in PulseDIA compared to conventional DIA and GPF. We further applied the PulseDIA method to profile the proteome of 18 human tissue samples (benign and malignant) from nine cholangiocarcinoma (CCA) patients. PulseDIA identified 7796 protein groups in these CCA samples, with a 14% increase of protein group identification compared to the conventional DIA method. The missing value for protein matrix dropped by 7% using PulseDIA compared to DIA. A total of 681 significantly altered proteins were detected in CCA samples using PulseDIA, including several dysregulated proteins, which were absent in the conventional DIA analysis. Taken together, we present PulseDIA as an enhanced DIA-MS method with improved sensitivity and reproducibility.

Here, ferric oxide-loaded metal-organic framework (FeTCPP/Fe2O3 MOF) nanorice was designed and constructed by the liquid diffusion method. The introduction of iron metal nodes and the loading of Fe2O3 can effectively catalyze the Fenton reaction to produce hydroxyl radicals (•OH) and overcome the hypoxic environment of tumor tissue by generating oxygen. The monodispersity and porosity of the porphyrin photosensitizers in the MOF structure exposed more active sites, which promoted energy exchange between porphyrin molecules and oxygen molecules for photodynamic therapy (PDT) treatment. Therefore, the generated hydroxyl radicals and singlet oxygen (1O2) can synergistically act on tumor cells to achieve the purpose of improving tumor therapy. Then the erythrocyte membrane was camouflaged to enhance blood circulation and tissue residence time in the body, and finally, the targeted molecule AS1411 aptamer was modified to achieve the high enrichment of MOF photosensitizers on a tumor domain. As a result, the MOF nanorice camouflaged by the erythrocyte membrane can effectively reduce side effects and improve the therapeutic effect of PDT and chemo-dynamic therapy (CDT). The study not only improved the efficacy of PDT and CDT in essence from the MOF nanorice but also used the camouflage method to further concentrate FeTCPP/Fe2O3 on the tumor sites, achieving the goal of multiple gains. These results will provide theoretical and practical directions for the development of tumor-targeted MOF nanomaterials.

We reported and evaluated a microflow, single-shot, short gradient SWATH MS method intended to accelerate the discovery and verification of protein biomarkers in preclassified clinical specimens. The method uses a 15 min gradient microflow-LC peptide separation, an optimized SWATH MS window configuration, and OpenSWATH software for data analysis. We applied the method to a cohort containing 204 FFPE tissue samples from 58 prostate cancer patients and 10 benign prostatic hyperplasia patients. Altogether we identified 27,975 proteotypic peptides and 4037 SwissProt proteins from these 204 samples. Compared to a reference SWATH method with a 2 h gradient, we found 3800 proteins were quantified by the two methods on two different instruments with relatively high consistency (r = 0.77). The accelerated method consumed only 17% instrument time, while quantifying 80% of proteins compared to the 2 h gradient SWATH. Although the missing value rate increased by 20%, batch effects reduced by 21%. 75 deregulated proteins measured by the accelerated method were selected for further validation. A shortlist of 134 selected peptide precursors from the 75 proteins were analyzed using MRM-HR, and the results exhibited high quantitative consistency with the 15 min SWATH method (r = 0.89) in the same sample set. We further verified the applicability of these 75 proteins in separating benign and malignant tissues (AUC = 0.99) in an independent prostate cancer cohort (n = 154). Altogether, the results showed that the 15 min gradient microflow SWATH accelerated large-scale data acquisition by 6 times, reduced batch effect by 21%, introduced 20% more missing values, and exhibited comparable ability to separate disease groups.

The pyrolysis of asphaltenes under hydrothermal environments covering the subcritical and supercritical regions of water was applied, and the influence of the presence of H-donors was surveyed by a reaction kinetics analysis based on the lumping approach. Under hydrothermal environments, the pyrolysis of asphaltenes consisting mainly of condensation to coke and decomposition to maltenes is significantly faster than that under a N2 environment. The H-donors introduced, decalin or maltenes, may provide nonaromatic H atoms, capping the carbon radicals essential to pyrolysis. Accordingly, the apparent activation energies of the condensation and the decomposition of asphaltenes both increase to varying degrees. The pyrolysis of asphaltenes in the presence of a small quantity of decalin is seriously retarded in subcritical water but recovers rapidly in supercritical water owning to the promoted initiation efficiency at high temperature. Accompanied by a large amount of maltenes, the decomposition to maltenes in...

Asphaltenes derived from the condensation of maltenes under high-pressure N2 and supercritical water (SCW) environments were characterized with various approaches. The reaction kinetics of the condensation of asphaltenes under hydrothermal environments were also measured. By improving the diffusivity of hydrocarbon species and the isolation of aromatic carbon radicals from hydrogen donors in the SCW phase, the dealkylation of alkyl substitutes and the condensation of aromatic rings involved in the condensation of maltenes are promoted. Consequently, asphaltenes formed in the SCW phase (As-SCW) have a higher aromaticity and lower alkyl and naphthenic fractions than asphaltenes formed in the oil phase (As-oil). Nevertheless, As-SCW and As-oil both present a cokelike supermolecular structure with the stacking of polycyclic aromatic rings. Benefitting from the highly fused aromatic molecular structure and the cokelike supermolecular structure, the condensation of As-SCW to coke occurs readily under hydrotherm...

Density functional theory calculations were carried out to study the charge transfer properties of bis(phthalocyaninato) yttrium and lanthanum double-decker complexes M(Pc)2 (M = Y, La) for organic field effect transistors. The results indicate that the intrinsic delocalized hole in M(Pc)2 (M = Y, La) induces the high energy level of highest occupied molecular orbital and low energy level of lowest unoccupied molecular orbital in the sandwich double-decker molecules as well as the small ionization potential and large electronic affinity. These factors lead to very small injection barrier relative to Au source-drain electrode of these two double-deckers for both hole and electron and render them as good potential ambipolar semiconductor. Associated with the very small reorganization energy for hole and electron and large transfer integral in crystal, these two complexes M(Pc)2 (M = Y, La) display intrinsic charge transfer mobility of 0.034 and 0.17 cm2 V−1 s−1 for hole and 0.031 and 0.088 cm2 V−1 s−1 for e...

Density functional theory calculations were carried out to investigate the effect of oligomer length, halogen substitution, and heteroatom substitution on the organic field-effect transistor (OFET) performance of a series of oligothienoacenes (1−5 for oligothienoacene with thiophene units' number from two to six). Compounds 1−5 are revealed to act only as p-type semiconductors due to their very high electron injection barrier relative to the work function potential of Au source-drain electrodes. Heteroatom substitution of the thiophene sulfur atom in particular with boron in the fused-ring thiophene oligomer 5 was revealed to elevate the HOMO energy level and lower the LUMO energy level and therefore lower both the hole and electron injection barriers. However, halogen substitution cannot effectively improve the electron injection barrier, but significantly increased the reorganization energy, therefore leading to decreased transfer mobility. The appropriate ionization potential and electron affinity, bal...

Density functional theory (DFT) calculations were carried out to describe the molecular structures, molecular orbitals, atomic charges, UV-vis absorption spectra, IR, and Raman spectra of bis(phthalocyaninato) rare earth(III) complexes M(Pc)(2) (M = Y, La) as well as their reduced products [M(Pc)(2)](-) (M = Y, La). Good consistency was found between the calculated results and experimental data. Reduction of the neutral M(Pc)(2) to [M(Pc)(2)]- induces the reorganization of their orbitals and charge distribution and decreases the inter-ring interaction. With the increase of ionic size from Y to La, the inter-ring distance of both the neutral and reduced double-decker complexes M(Pc)(2) and [M(Pc)(2)](-) (M = Y, La) increases, the inter-ring interaction and splitting of the Q bands decrease, and corresponding bands in the IR and Raman spectra show a red shift. The orbital energy level and orbital nature of the frontier orbitals are also described and explained in terms of atomic character. The present work, representing the first systemic DFT study on the bis(phthalocyaninato) yttrium and lanthanum complexes sheds further light on clearly understanding structure and spectroscopic properties of bis(phthalocyaninato) rare earth complexes.