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We have developed a sensitive and rapid gold nanoparticle-based immunochromatographic strip (GNP-ICS) for the detection of phenacetin (PNCT) and paracetamol (PAP) using an anti-PNCT monoclonal antibody (mAb). The sensitive anti-PNCT mAb (2D6) had a half maximal inhibitory concentration (IC50) and limit of detection (LOD) of 3.51 and 0.21 ng mL−1, respectively. Additionally, its cross-reactivity with PAP was approximately 10.1%. The developed GNP-ICS assay based on GNP-labeled mAb was sensitive for the detection of PNCT with vLOD and cut-off values of 2.5 and 50 ng mL−1 respectively and a vLOD value of 25 ng mL−1 for PAP. Furthermore, the developed icELISA and GNP-ICS assays were applied to determine PNCT-spiked beverage samples without pretreatment, in addition to a kind of PAP-containing drug. The recoveries were validated using high performance liquid chromatography (HPLC). The results revealed that the developed GNP-ICS assay was reliable for the detection of PNCT in practical samples. [ABSTRACT FROM AUTHOR]

This report describes the development of a sensitive and broadly specific indirect competitive enzyme-linked immunosorbent assay (icELISA) and a gold nanoparticle-based immunochromatographic strip (GNP-ICS) assay for the detection of benzo[a]pyrene (B[a]P), using an anti-B[a]P monoclonal antibody (mAb). A broad-specific anti-B[a]P mAb (4E8) was raised from two types of haptens, with half maximal inhibitory concentrations and limits of detection (LOD) values of 2.51 and 0.54 ng mL−1, respectively. In addition, the cross-reactivity was up to 390% with structurally related compounds. The GNP-ICS assay based on a GNP-labeled mAb showed broad specificity in the detection of B[a]P and its analogues, with cut-off and visual LOD values of 100 and 10 ng mL−1, respectively. Furthermore, the recoveries from the developed icELISA and GNP-ICS assay in edible oil samples spiked with B[a]P were validated by high-performance liquid chromatography–fluorescence detection. The results revealed that the icELISA could reliably detect B[a]P in edible oils. [ABSTRACT FROM AUTHOR]

In this work, GaN crystals were grown on non-polar and semi-polar HVPE GaN seeds by the basic ammonothermal method. The growth behaviors of various crystal planes were investigated. Different surface morphology regimes were observed with features including hillock-, slate- and elliptical sphere-like surfaces. The growth rates and evolution processes of various planes of the as-grown GaN crystals were characterized using scanning electron microscopy (SEM) and cathodoluminescence (CL) measurements. Our results suggest that the growth rates of identical crystal planes grown on HVPE seeds with different orientations are almost the same. The dominant facets of these GaN crystals were ultimately found to be non-polar m-planes, {10−11} semi-polar planes and polar (000−1) planes by analyzing the morphological evolution of the crystal shape using the kinetic Wulff's rule. [ABSTRACT FROM AUTHOR]

In order to demonstrate the influence of structural fine-tuning on bandgap and semiconductor performance of π-conjugated polymer materials, three new diketopyrrolopyrrole (DPP) based copolymers P1, P2 and P3 with monomers, i.e., 2-phenylpyridine, 2-(thiophen-2-yl)pyridine and 2-(thiophen-2-yl)thiazole, respectively, have been synthesized using a typical Suzuki cross-coupling polycondensation. The DFT calculations demonstrate that polymer P3 displays high backbone coplanarity in comparison to polymers P1 and P2. Absorption spectra results reveal that P3 exhibits a remarkable red-shifted absorption profile, narrow band gap and broad absorption. The thin film FET measurements show that P3 possesses the highest hole mobility (μh) up to 1.25 cm2 V−1 s−1 and on/off (Ion/off) ratio as high as 108. Those results demonstrate that the fine-tuning of the π-conjugated backbone can significantly affect the band gaps and coplanarities, and ultimately improve the semiconducting performances. [ABSTRACT FROM AUTHOR]

In this paper, we report two conjugated molecules 1 and 2 with four diketopyrrolopyrrole (DPP) moieties, which are linked by [2,2]paracyclophane. The energies of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of 1 and 2 were estimated from the respective onset oxidation and reduction potentials, which were determined on the basis of cyclic voltammetric data. Both 1 and 2 exhibit strong absorption in the visible region. Blended thin films of 1 and 2 with P3HT (poly(3-hexylthiophene)) in different weight ratios were utilized as active layers to fabricate solar cells. The results reveal that blended thin films of P3HT/1 and P3HT/2 at a weight ratio of 2 : 1 yielded the best photovoltaic performance with power conversion efficiencies (PCEs) up to 1.33% and 1.84% after thermal annealing. Blended thin films of P3HT/1 and P3HT/2 were characterized by XRD (X-ray diffraction) and AFM (atomic force microscopy) techniques. The low degree of inter-chain packing order and poor thin-film morphology are responsible for the relatively low PCEs. [ABSTRACT FROM AUTHOR]

In this paper we report two DPP-based conjugated molecules DPPBT and DPPTT in which the respective electron withdrawing moieties 2,1,3-benzothiadiazole and thiazolo[5,4-d]thiazole are flanked by two DPP moieties. For comparison, DPPBZ containing 1,4-diethynylbenzene and two DPP moieties were synthesized. HOMO/LUMO energies of DPPBT, DPPTT and DPPBZ were estimated on the basis of cyclic voltammetric data. Owing to the fact that LUMO energies of DPPBT and DPPTT were lowered to ca.−3.5 eV, thin films of both DPPBT and DPPTT exhibit ambipolar semiconducting properties under N2 atmosphere with hole and electron mobilities up to 0.25 cm2 V−1 s−1 and 0.09 cm2 V−1 s−1, respectively. In comparison, thin film of DPPBZ just shows p-type semiconducting property. Notably, ambipolar semiconductors with relatively high carrier mobility are rarely reported for DPP-containing small conjugated molecules. Alternatively, both DPPBT and DPPTT can function as electron donors for photovoltaic materials. Thin films of DPPTT:PC71BM and DPPBT:PC71BM at a weight ratio of 1 : 1 exhibit PCEs of 4.18% and 2.44%, respectively, with VOC higher than 0.95 V. [ABSTRACT FROM AUTHOR]

A new method to label and detect the long ssDNA products from rolling circle (RC) amplification was reported. ZnS nanocrystal clusters (NCCs) were used to tag the RC products. The NCCs release millions of cations to trigger millions of metal-responsive dyes for cascade signal amplification. Selective and sensitive quantification of miRNA was demonstrated; and the NCCs delivered much lower detection limits compared to using peroxidase or quantum dots as the labels. [ABSTRACT FROM AUTHOR]

A simple and sensitive approach to detect Hg2+colorimetrically using blotting membrane is described to detect as low as 0.1 nM Hg2+with the aid of a scanner. [ABSTRACT FROM AUTHOR]

Although zinc oxide nanoparticles (ZnO NPs) with distinct physicochemical properties have attracted great attention, the application of ZnO NPs is still limited due to their potential biotoxicity. In this work, ZnO- Polygonatum sibiricum (PS) NPs are synthesized to overcome this challenge. The ZnO NPs stably combine with PS according to microstructural observation, particle size distribution, zeta potential results and Fourier transform infrared spectroscopy analysis. The cytotoxicity of ZnO NPs is alleviated by combining them with PS as a consequence of the diminished generation of reactive oxygen species and reinforced superoxide dismutase activity. Furthermore, the respiratory index and histopathologic results of mice exposed to NPs manifest that the pulmonary dysfunction caused by ZnO NPs is avoided in the ZnO-PS NPs group. This study provides the foundations for the amelioration and universal utilization of ZnO NPs and emphasizes the potential of ZnO-PS NPs in biomedical applications., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Two conjugated molecules with a [2,2]paracyclophane core were designed as non-fullerene electron acceptors for photovoltaic cells. Using as the donor, a high power conversion efficiency (2.69%) is achieved for the blending thin film of with , which is relatively high for solution-processed OPVs based on small molecular non-fullerene acceptors and as the electron donor.

A sensitive and simple assay for the detection of Pb(2+) in aqueous solutions is reported. It takes advantage of the high affinity between single-stranded DNA (ssDNA) and single-walled carbon nanotubes (SWCNT) as well as the capability of SWCNT in fluorescence quenching. Lead(II) catalyzes the cleavage of a fluorescently labeled DNA substrate by a DNAzyme, which releases the single-stranded product to be adsorbed onto a SWCNT. The decrease in fluorescence is proportional to the Pb(2+) concentration. Concentrations as low as 1 nM Pb(2+) in water could be detected and the detection range spans over 5 orders of magnitude. The unique combination of Pb-specific DNAzyme with SWCNT produces a universal, facile and cost-effective sensing platform for lead ions. The concept can be applied to the design of detection assays for other metal ions or small molecules.