Search

Spin to charge conversion process in a broad range of temperatures is studied in La0.92MnO3/Pt bilayers prepared by polymer-assisted deposition (PAD). It is shown that an excellent LMO/Pt interface can be obtained in spite of using ex situ deposition of the Pt layer. The values obtained for the effective spin-mixing conductance, g ↑↓eff = 0.76 × 1015 cm−2, suggest that significant spin transport across the LMO/Pt interface could be achieved. Spin pumping experiments generate a transversal voltage signal VISHE, due to spin to charge conversion via inverse spin Hall effect, that has been detected down to about 100 K with values of the spin-Hall angle, SH, of about 2.5%, slightly decreasing on reducing temperature in the analyzed temperature range. These results indicate that LMO is a promising perovskite building block for all-oxide multifunctional high-frequency spintronics devices and that PAD technique provides oxide epitaxial thin films of good quality adequate for spintronic applications. [ABSTRACT FROM AUTHOR]

Here we establish a one-pot reaction to directly convert the DNA base 5-hydroxymethylcytosine (5hmC) to an intramolecular cyclization nucleobase, which loses both protons of the exocyclic N4-amino group and thus is recognized as thymine (T) by DNA polymerase. Based on this 5hmC-specific reaction, a prospective bisulfite-free strategy for 5hmC sequencing is proposed. This is also the first example to show modified DNA labeling in non-water solvent-dominant media for DNA sequencing. [ABSTRACT FROM AUTHOR]

Monitoring of over-expressed nucleolin in the cytoplasm facilitates early cancer diagnosis. Herein, we present a novel biosensing nanoscaffold based on anti-nucleolin aptamers and polymer-grafted graphene oxides for the fluorescent imaging of nucleolin in the cell cytoplasm, which can distinguish cancer cells from normal cells. [ABSTRACT FROM AUTHOR]

By identification of a super-stable protein–DNA-affinity system, we developed a free-solution capillary electrophoresis approach for rapid and sensitive detection of fundamentally important DNA strand exchange reactions mediated by recombinases. We further extended this assay for identification of hyper-recombinases generated from bioengineering and detection of single DNA mismatches caused by replication error. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is a mycotoxin that can cause health risks to human/animal health. Contamination by OTA can occur in various foods and agricultural products, so sensitive and rapid detection of OTA is crucial. We describe a simple and sensitive fluorescence immunoassay for OTA using tetramethylrhodamine (TMR)-labeled OTA as a fluorescent probe. We conjugated tetramethylrhodamine to OTA through a covalent reaction, and obtained three TMR-OTA isomer probes after purification by high-performance liquid chromatography. All of the fluorescent probes showed high binding affinity to the anti-OTA antibody. Binding of the TMR-OTA probe to the antibody induced strong fluorescence of TMR-OTA due to the possible change in the local environment of TMR caused by affinity binding. In the presence of OTA, the OTA target competitively displaced the bound TMR-OTA probe from the antibody, causing a decrease in fluorescence. Measuring the change in fluorescence enabled rapid detection of OTA. This method was selective and allowed the detection of 1 nM OTA, showing potential for rapid OTA analysis in applications. [ABSTRACT FROM AUTHOR]

Complex oxide thin films grown by using chemical methods are of strong interest because of their low-cost, environment friendly fabrication and easy scalability. However, their introduction in spintronic applications or magnetic devices is still scarce mainly because of concerns regarding their interfacial quality. Here, we report on the preparation by polymer-assisted-deposition (PAD) of epitaxial La0.92MnO3 (LMO) thin films. We demonstrate that ferromagnetic conducting LMO thin films with smooth surfaces (rms ∼ 0.2 nm) can be prepared by PAD. By means of temperature-dependent broadband ferromagnetic resonance (FMR), we show that the LMO film exhibits a four-fold in-plane anisotropy, with [110] being the easy in-plane axis, compatible with strain release from the rhombohedral bulk phase. It has also been found that the isotropic Gilbert damping, α, determined from the broadening of the FMR linewidth, does not show a relevant extrinsic contribution and it exhibits an intraband-like temperature dependence, i.e. it increases as temperature decreases. By capping LMO thin films with a 10 nm thick Pt layer deposited ex situ, damping is substantially enhanced, from a value at 150 K of αLMO ∼ 1 × 10−2 for the bare LMO film to αLMO+Pt ∼ 2.5 × 10−2 for the Pt capped film. This strong increase of magnetic damping is indicative of the transfer of spin momentum from LMO to the Pt layer by spin pumping. Our results demostrate that LMO films grown by PAD may be used as efficient spin source systems in heterostructures for spintronic devices. [ABSTRACT FROM AUTHOR]

Exogenous and endogenous genotoxic carcinogens and their in vivo metabolites may result in DNA damage and cause adverse health effects. It is very difficult to specifically detect trace DNA damage in the presence of a large excess of unmodified nucleosides. Here we report a molecularly imprinted polymer (MIP) nanocomposite, namely nanoMIP, which can be used as a “plastic antibody” for specific recognition of benzo[a]pyrene diol epoxide (BPDE)–DNA adduct. Enhanced binding affinity (880 nM) of nanoMIPs was achieved by using two tailor-made functional monomers. The property of binding kinetics was greatly improved in virtue of the well-defined nanostructure, which was fabricated by initiators for continuous activator regeneration-atom transfer radical polymerization (ICAR-ATRP). The BPDE-adducted DNA can be specifically captured by synthetic nanoMIP. By taking advantage of this antibody-mimicking behavior, we further developed a fluorescently imaged particle counting immunoassay (FIPCIA) method for ultrasensitive detection of BPDE–ssDNA adducts using a laser scanning confocal microscope (LSCM). The number of countable fluorescent dots is proportional to the content of BPDE–ssDNA adducts in the DNA sample. The proposed plastic antibody-based FIPCIA method can detect traces of BPDE–DNA adducts as low as 18 pM in human lung carcinoma A549 cells. This highly-sensitive detection of DNA lesions offers a promising alternative to immunogenic antibody-based immunoassays for genomics and DNA modification analysis. [ABSTRACT FROM AUTHOR]

Triphenylsulfonium chloride (TPSC) was employed as a bifunctional agent for the selective enrichment of perfluoroalkyl sulfonates by triphenylsulfonium perfluorosulfonic acid (TPA, a photoacid generator) precipitation, and for the direct detection of perfluorosulfonic acid by MALDI-TOF-MS, using the triphensylsulfonium group of TPA as a matrix. [ABSTRACT FROM AUTHOR]

Molecularly imprinted nanotubes for enantioselective drug delivery and controlled release are fabricated by the combination of template synthesis and ATRP grafting. The release of R-propranolol from the imprinted nanotubes in rats is restricted while the release of pharmacologically active S-enantiomer is greatly promoted. [ABSTRACT FROM AUTHOR]

Selective cleavage of both active and inert C–C bonds in substituted allylcyclopropanes was realized viaa novel ligand-controlled approach using zirconocene(ii)-1-butene or zirconocene(ii)-benzyne complexes. [ABSTRACT FROM AUTHOR]

Breast cancer is the most prevalent malignant disease among women across the globe. Notably, estrogen signaling plays a vital role in the progression of estrogen receptor-positive breast cancer. Therefore, targeting epigenetic regulators is a promising therapy for cancer. To identify epigenetic regulators, we conducted a siRNA screening targeting 140 epigenetic genes by which 32 positive and 15 negative regulators of estrogen signaling were obtained. The protein-protein interaction network of the candidate genes was constructed and the topological parameters of the network were calculated. As a result, the top 10 genes with higher MCC (Maximal Clique Centrality) scores were considered as hub genes. Notably, the hub genes all belong to polycomb group genes. The transcription levels of the above genes were compared between breast cancer and normal tissues using the UALCAN database. Then, the survival analysis of the hub genes was conducted using the Kaplan-Meier Plotter online database. Lastly, the effect of hub genes on MCF-7 cell proliferation and ER target gene expression were investigated. These results indicate that PcG genes regulate estrogen signaling and breast cancer development.

1,8-Bis(dimethylamino)naphthalene (DMAN), a classical 'proton sponge', was functionalized on silica particles as a novel solid-phase extraction (SPE) adsorbent (DMAN@silica) for extracting perfluoroalkyl sulfonates (PFSs). High reproducibility and excellent extraction capability for PFSs were obtained in a wide pH range (3.0~8.5). The adsorbed PFSs on DMAN@silica sorbents could be efficiently eluted by 1,8-bis(tetramethylguanidino)naphthalene (TMGN) solution which is a proton sponge with higher proton affinity than DMAN. The elution could be directly analyzed by MALDI-TOF-MS using TMGN as matrix. Clear mass spectra for the PFSs were obtained due to no matrix ions interference observed. Furthermore, a novel strategy based on the DMAN@silica-SPE enrichment, followed by MALDI-TOF-MS analysis, was proposed and applied for PFSs quantification in environmental water samples. The calibration curves of each of the target analytes showed a wide linear dynamic range of response (0.1-10 ng L(-1) for perfluorooctane sulfonate (PFOS), perfluorohexyl sulfonate (PFHxS) and perfluorobutylsulfonate (PFBS)), which were over 2 orders of magnitude. The detection limits for PFOS, PFHxS, and PFBS were 0.021, 0.016, and 0.013 ng L(-1), respectively (S/N = 3). Recoveries of PFOS, PFHxS, and PFBS are in the ranges of 92-104%, 95-102%, and 98-109% for spiked river water samples. These results indicated that the prepared DMAN@silica adsorbents could efficiently enrich PFSs and that the proposed method is reliable.

We have found a new way, a metal-organic coordination gel template method, to generate polymer monoliths with an essentially macropore size, in which the pores are organized spontaneously into continuous networks; furthermore, the resulting macroporous monoliths have potential applications in high-throughput and high-efficiency separation of proteins.