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Aflatoxin B1 (AFB1) is a powerful carcinogen, and the pollution it causes has become a global public health safety issue. Therefore, microfluidic paper-based analytical devices (μPADs) with smartphones to read colorimetric signals were constructed for rapid AFB1 detection. The colorimetric mechanism of μPADs was based on the common starch–iodine reaction, and the addition of gelatin/chitosan enhanced the colorimetric effect. During detection and analysis, the competitive analysis occurred in the process of AFB1 monoclonal antibody's recognition of free AFB1 and functionalized antigen. The glucose oxidase-labeled IgG was used as the secondary antibody. Hydrogen peroxide, an oxidation product of the glucose, caused a chroma change in μPADs. Simultaneously, the change in chroma was consistent with the change in AFB1 concentration. Under the best optimized conditions, the limits of detection and quantitation of AFB1 in the buffer were 9.45 and 12.00 ng mL−1, respectively. A comparison of the detection performance of commercial kits with that of the method introduced herein confirmed the superiority of our method in actual food samples with known AFB1 concentrations. This colorimetric μPADs analysis met the detection requirements of some countries, such as China, and had great potential for development in the direction of daily extensive food safety control and environmental monitoring.

PEDOT:PSS-based conductive films have emerged as promising next-generation flexible transparent electrodes. However, the PEDOT:PSS-based electrodes suffer from poor electrical conductivity with extremely large mechanical deformation, owing to generation of defects, or partial exfoliation of PEDOT:PSS film from the underlying substrates. Herein, we report an intrinsic flexible conductive PEDOT:PSS@P[VEIm][DCA] composite film prepared by combining poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) with cross-linked poly(1-vinyl-3-ethylimidazolium dicyanamide) (P[VEIm][DCA]) ionogel, which exhibits high conductivity and transparency with negligible changes under harsh environmental conditions. The cross-linked P[VEIm][DCA] network can endow the composite film not only with excellent free-standing property, but also significantly enhanced electrical conductivity. We have successfully incorporated the PEDOT:PSS@P[VEIm][DCA] composite film into wearable touch panel device. We believe that the designed PEDOT:PSS@ionogel composite film is making an important step toward applications in flexible electronic and optoelectronic devices including touch panels, displays and so on.

Lingaoamide (1), a new cyclic heptapeptide natural product, was isolated from a freshwater Oscillatoria cyanobacterium. The producing organism was collected in Chinese water spinach paddy farm fields in Lingao County, Hainan, China. The structure of 1 was determined by conventional mass spectrometry, NMR spectroscopy, and chemical degradation studies. Lingaoamide concentration-dependently up-regulates the biogenesis of pro-pathogenic melanin pigments (melanogenesis) in the rice blast fungus, Magnaporthe grisea, when tested in vitro. This molecule also exhibits weak in vitro inhibition (MIC 32 μg/mL) of Gram-negative Pseudomonas aeruginosa and Gram-positive Bacillus pumilus, and does not appear to impact plant growth or immune response in vivo using the model organism, Arabidopsis thaliana.