A multilayered glucose biosensor via sequential deposition of Prussian blue (PB) nanoclusters and enzyme-immobilized poly(toluidine blue) films was constructed on a bare Au electrode using electrochemical methods. The whole configuration of the present biosensor can be considered as an integration of several independent hydrogen peroxide sensing elements. In each sensing element, the poly(toluidine blue) film functioned as both the supporting matrix for the glucose oxidase immobilization and the inhibitor for the diffusion of interferences, such as ascorbic acid and uric acid. Meanwhile, the deposited Prussian blue nanocluster layers acts as a catalyst for the electrochemical reduction of hydrogen peroxide formed from enzymatic reaction. Performance of the whole multilayer configuration can be tailored by artificially arranging the sensing elements assembled on the electrode. Under optimal conditions, the biosensors exhibit a linear relationship in the range of 1 x 10(-4) to 1 x 10(-2) mol/L with the detection limit down to 10(-5) mol/L. A rapid response for glucose could be achieved in less than 3 s. For 1 mM glucose, 0.5 mM acetaminophen, 0.2 mM uric acid, and 0.1 mM ascorbic acid have no obvious interferences (<5%) for glucose detection at an optimized detection potential. The present multilayered glucose biosensor with a high selectivity and sensitivity is promising for practical applications.

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Previous studies have shown that increasing estradiol concentrations had a toxic effect on the embryo and were deleterious to embryo adhesion. In this study, we evaluated the physiological impact of estradiol concentrations on endometrial cells to reveal that serum estradiol levels probably targeted the endometrium in controlled ovarian hyperstimulation (COH) protocols. An attachment model of human choriocarcinoma (JAr) cell spheroids to receptive-phase endometrial epithelial cells and Ishikawa cells treated with different estradiol (10−9 M or 10−7 M) concentrations was developed. Differentially expressed protein profiling of the Ishikawa cells was performed by proteomic analysis. Estradiol at 10−7 M demonstrated a high attachment rate of JAr spheroids to the endometrial cell monolayers. Using iTRAQ coupled with LC–MS/MS, we identified 45 differentially expressed proteins containing 43 significantly upregulated and 2 downregulated proteins in Ishikawa cells treated with 10−7 M estradiol. Differential expression of C3, plasminogen and kininogen-1 by Western blot confirmed the proteomic results. C3, plasminogen and kininogen-1 localization in human receptive endometrial luminal epithelium highlighted the key proteins as possible targets for endometrial receptivity and interception. Ingenuity pathway analysis of differentially expressed proteins exhibited a variety of signaling pathways, including LXR/RXR activation pathway and acute-phase response signaling and upstream regulators (TNF, IL6, Hmgn3 and miR-140-3p) associated with endometrial receptivity. The observed estrogenic effect on differential proteome dynamics in Ishikawa cells indicates that the human endometrium is the probable target for serum estradiol levels in COH cycles. The findings are also important for future functional studies with the identified proteins that may influence embryo implantation.

A series of coals of varying rank, from brown coal to anthracite, were studied by Fourier transform infrared spectroscopy (FTIR). Curve-fitting analysis was employed to characterize coal structural evolution during the coalification process. The study was carried out on samples of a natural evolutionary series as well as experimental simulation coals dispersed on KBr pellets throughout the Ordos Basin, China. The results showed that the infrared spectrum of coal allowed quality and even quantity identification of the degree of coalification. Oxygen-containing groups and alkyl side chains of coal cracked at different rates with increasing degree of coalification. The cracking rates were divided into three stages according to the main changes in coal structure. These stages were carboxyl groups, fat groups and aromatic rings. Carboxyl groups decreased when R o was less than 0.5%, and these groups were maintained until the fat coal stage began. Fat groups mainly cracked at the asphaltization stage and formed abundant hydrocarbons. These groups were the main sources for the formation of immature and low maturity, coal-generating oil before asphaltization. In the high evolutionary stage, after asphaltization, all alkyl side chains in the coal had cracked, while the degree of condensed aromatic rings had increased greatly. The ratios of aromatic hydrocarbons (3000 to 3100 cm Ϫ1 ) to aliphatic carbons (2800 to 3000 cm Ϫ1 ), CH 2 /CH 3 (2920/2950 cm Ϫ1 ) and carboxyl groups to aromatic carbons (1705/1620 cm Ϫ1 ϩ 1600cm Ϫ1 ϩ 1580 cm Ϫ1 ) appeared to be suitable parameters for assessing the natural maturation of coal.