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• Effect of hydrogen, helium and dose rate on the evolution of dislocation loops were in-situ studied in detail. • Triple-beam (Fe++H 2 ++He+) irradiation significantly promoted the nucleation and growth of dislocation loops. • Dose rate affected loop type. The higher the dose rate, the lower the fraction of 〈100〉 loops. • The ratio of rotated loops was highest under triple-beam (Fe++H 2 ++He+) irradiation. Simulating neutron irradiation with ion irradiation requires considering the comprehensive effects of hydrogen, helium and dose rate to fully understand the microstructure evolution of material in an irradiation environment. Here, the characterization and evolution of dislocation loops in pure iron were investigated under heavy ion irradiation with four different injected gas ion types (Fe+, Fe++H 2 +, Fe++He+and Fe++H 2 ++He+) and under dual-beam (Fe++He+) irradiation with four different dose rates using in-situ transmission electron microscopy at 723 K. Comparing to the single-beam (Fe+) irradiation, the additional injection of H or He, or co-injected H and He, mainly promoted the nucleation of dislocation loops at the early stage of irradiation and enhanced loop growth after that. Among them, the simultaneous irradiation of triple beams (Fe++H 2 ++He+) was most pronounced. Moreover, triple-beam (Fe++H 2 ++He+) irradiation resulted in the highest ratio of the rotation of loop habit-plane. Under dual-beam (Fe++He+) irradiation, the results demonstrated that as the dose rate increased, the loop density increased and the loop size decreased. Moreover, the fraction of 〈100〉 loops at low dose rate was noticeably greater than that at high dose rate. The results of the current work provide important references for a better understanding of the effectiveness of ion irradiation in simulating neutron irradiation. [Display omitted] [ABSTRACT FROM AUTHOR]

The demand for ultrasensitive and inexpensive biosensors is always strong due to increasing healthcare related concerns. Herein, we developed a simple method to prepare uniform, reliable, high yield, and low-cost two-dimensional (2-D) polyaniline layer for biosensor applications. The 2-D PANI layer’s surface morphology led to a 46% increase in surface area compared to a flat 2-D surface. Due to this unique morphology and excellent semiconducting properties, the 2-D PANI layer exhibited ultrasensitive performance with excellent specificity on BNP biomarker detection in fixed Debye length condition, which is comparable to or even higher than 1-D nanostructure biosensors. In further Debye length investigation, we have observed signal changes that are varied from 8 nA to 16 nA with Debye length changes from 0.5 nm to 3.3 nm for constant BNP concentration. This result shows an improvement in device sensitivity over increasing Debye length, which conforms to Debye screening theory. With the high specificity of over 400 fold, the PANI layer was capable of monitoring significantly low BNP levels in human serum, as low as 50 pg/mL. Our findings provide an opportunity for the realization of ultrasensitive and inexpensive biosensors for clinical use. [ABSTRACT FROM AUTHOR]

Abstract: Single polypyrrole (PPy) nanowire-based microfluidic aptasensors were fabricated using a one-step electrochemical deposition method. The successful incorporation of the aptamers into the PPy nanowire was confirmed by fluorescence microscopy image. The microfluidic aptasensor showed responses to IgE protein solutions in the range from 0.01nM to 100nM, and demonstrated excellent specificity and sensitivity with faster response and rapid stabilization times (∼20s). At the lowest examined IgE concentration of 0.01nM, the microfluidic aptasensor still exhibited ∼0.32% change in the conductance. The functionality of this aptasensor was able to be regenerated using an acid treatment with no major change in sensitivity. In addition, the detection of cancer biomarker MUC1 was performed using another microfluidic aptasensor, which showed a very low detection limit of 2.66nM MUC1 compared to commercially available MUC1 diagnosis assay (800nM). [Copyright &y& Elsevier]

Abstract: Recognition and separation of chiral molecules is of great importance in the field of biotechnology, especially on pharmaceutics. Molecular imprinted polymers (MIP) have been proved as a powerful tool for the separation of target molecules. In this paper, polypyrrole (PPy) nanowires with an average diameter of ca. 100nm and few micrometers in length were successfully prepared by electrochemical polymerization, in which enantiomeric camphorsulfonic acid (d- or l-CSA) molecule acted as both the dopant and molecular imprinting pseudo-template. Both electrochemical impedance spectra (EIS) and circular dichroism (CD) spectra were employed to demonstrate the enantioselective interaction between de-doped PPy nanowires imprinted with CSA enantiomers (MIP-PPy) and chiral phenylalanine (d- or l-Phe). EIS leads to the characterization of interfacial electron resistance of the PPy coated electrode, while CD spectra provides spectral evidence for the enantioselective recognition event. Both methods proved that MIP-PPy nanowires have the capability for the recognition and separation of chiral phenylalanine. The sensitivity of the chiral recognition was further investigated by using various concentrations of chiral Phe and adsorption time. This approach provides a potential route for fabricating enantioselective recognition polypyrrole nanostructures that could be employed in enantiomeric sensoring or separating various chiral molecules. [Copyright &y& Elsevier]

The objective of this study was to investigate the antioxidant and enzyme inhibitory activity, and characterize the bioactive constituents of the phenolic extract of Potentilla discolor Bge. Dry material of Potentilla discolor Bge. was extracted with 80% ethanol solution to obtain the crude phenolic extract (CPE) with the total phenolic content (TPC) of 20.40 ± 0.69 mg of gallic acid equivalents per gram of dry material (mg GAE/g DM). After purified with AB-8 macroporous resin, TPC of the purified phenolic extract (PPE) (353.65 ± 5.50 mg GAE/g DM) was much higher than that of the CPE. PPE exhibited stronger 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and 2,2′-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity than CPE and 2,6-Di-tert-butyl-4-methylphenol (BHT), with the IC50 values of 0.030 ± 0.002 mg/mL and 0.059 ± 0.002 mg/mL, respectively. The total antioxidant activities of PPE and BHT were similar, and were higher than CPE. PPE was found to significantly inhibit α-amylase and α-glucosidase with IC50 values of 0.966 ± 0.072 and 2.431 ± 0.088 mg/mL, respectively. Finally, using UPLC-TOF–MS/MS technology, 35 compounds were tentatively identified, including 12 phenolic acids, 23 flavonoids and their derivatives, 29 of which have been discovered for the first time in Potentilla discolor Bge. These results suggested that PPE had the potential to be used as an antioxidant and anti-diabetic component in functional foods. [ABSTRACT FROM AUTHOR]

Drug‐induced liver injury (DILI) is one of the common adverse effects of drug therapy, which is closely associated with oxidative stress, apoptosis, and inflammation response. Medium‐chain fatty acids (MCFA) were reported to relieve inflammation and attenuate oxidative stress. However, little has been known about the hepatoprotective effects of MCFA in DILI. In the present study, acetaminophen (AP) and rifampicin (RFP) were used to establish DILI models in LO2 cells, and the cytoprotective effects of MCFA on hepatocellular injury were investigated. Results showed that the optimal condition for the DILI model was treatment with 10 mM AP or 600 µM RFP for 24 hr. LCFA treatment markedly reduced the cell viability and increased the activities of alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase. Meanwhile, LCFA treatment aggravated cell apoptosis, mitochondrial dysfunction, and oxidative stress. The mRNA and protein expression levels of inflammatory cytokines (IL‐1β and TNF‐α) were significantly elevated by LCFA. In contrast, MCFA treatment did not significantly affect cell viability, apoptosis, oxidative, stress and inflammation, and it did not produce the detrimental effects on DILI models. Therefore, we proposed that MCFA may be more safe and suitable than LCFA as nutrition support or the selection of daily dietary oil and fat for the patients with DILI. [ABSTRACT FROM AUTHOR]

A highly sensitive, conductometric and label-free biosensor for the detection of immunoglobulin E (IgE) is developed based on the immobilzation of the IgE aptamer onto a single polyaniline nanowire electrochemically synthesized in a facile and controllable way. [ABSTRACT FROM AUTHOR]