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For systems containing oil–water mixtures, such as oil spills, contaminated groundwater, various industrial processes, etc., it is often desirable to selectively capture the oil phase. Here, we demonstrate transpiration-powered oil sequestration in a synthetic tree when its roots are placed in an oil–water bath. As water transpired from the nanoporous synthetic leaf, driven by the negative Laplace pressure of concave menisci within the nanopores, oil preferentially entered the tree via membranes that were oleophilic and hydrophobic. Both filtration and the subsequent pumping against gravity of oil up the tree's vertical tube array were spontaneously powered by transpiration. After the tree's precharged water was fully evaporated, liquid samples extracted from the tree were ≈96–100% pure oil as measured from refractometry and gravimetry. [ABSTRACT FROM AUTHOR]

Efficient capture of target analyte on biosensor platforms is a prerequisite for reliable and specific detection of pathogenic microorganisms in a microfluidic chip. Antibodies have been widely used as ligands; however, because of their occasional unsatisfactory performance, a search for alternative receptors is underway. Heat shock protein 60 (Hsp60), a eukaryotic mitochondrial chaperon protein is a receptor for Listeria adhesion protein (LAP) during Listeria monocytogenes infection. This paper reports application of biotinylated Hsp60 as a capture molecule for living (viable) L monocytogenes in a microfluidic environment. Hsp60, immobilized on the surface of streptavidin-coated silicon dioxide exhibited specific capture of pathogenic Listeria against a background of other Listeria species, Salmonella, Escherichia, Bacillus, Pseudomonas, Serratia, Hafnia, Enterobacter, Citrobacter, and Lactobacillus. The capture efficiency of L monocytogenes was 83 times greater than another Listeria receptor, the monoclonal antibody, mAb-C11E9. Additionally, the capture rate was further increased on a Hsp60-coated biochip by 60% when a dielectrophoresis force was applied for 5 min at the beginning of the final 1 h incubation step. Our data show that Hsp60 could be used for specific detection of L monocytogenes on a biochip sensor platform.

A sandwich fluorescent immunoassay in a microarray format was used to capture and detect E. coli O157:H7. Here, we explored quantitative aspects, limitations, and capture efficiency of the assay. When biotinylated capture antibodies were used, the signal generated was higher (over 5-fold higher with some cell concentrations) compared to biotinylated protein G-bound capture antibodies. By adjusting the concentration of reporter antibody, a linear fluorescent response was observed from ~3.0 x [10.sup.6] to ~9.0 x [10.sup.7] cells/mL, and this was in agreement with the number of captured bacteria as determined by fluorescence microscopy. Capture efficiency calculations revealed that, as the number of bacteria presented for capture decreased, capture efficiency increased to near 35%. Optimization experiments, with several combinations of capture and reporter antibodies, demonstrated that the amount of bacteria available for capture ([10.sup.6] versus [10.sup.8] cells/mL) affected the optimal combination. The findings presented here indicate that antibody microarrays, when used in sandwich assay format, may be effectively used to capture and detect E. coli O157:H7.

An enantioselective first total synthesis and structural revision of the cytotoxic natural product amphidinolide W is described. Optical rotation of amphidinolide W is reported for the first time after total synthesis and amphidinolide W and its diastereomers are very unstable and prone to decomposition even when they are stored at low temperatures.

Poly(3-hexyl thiophene) (P3HT) organically modified montmorillonite (om-MMT) polymer nanocomposites (PNCs) are prepared in the melt-cooled state. The hierarchical structures up to third order, namely, side chain mesomorph formation followed by the interchain lamellar structure of P3HT and finally its intercalation within the clay is observed.

An NAMFIS deconvolution analysis for laulimalide in DMSO-d6 is performed to examine the conformational energy surface of laulimalide. 15 laulimalide conformations are identified that can be classified into 5 different families, Supine, Convex, Cobra, Strech, and Concave motifs.

The syntheses of dibenzo[c,p]chrysne, its proximate carcinogens and possible ultimate carcinogens are reported. The results show that the synthesis of dibenzo[c,p]chrysne and its metabolites by Suzuki coupling sequence is possible but the overall yield is low.

A convenient synthesis of (3R,3aS,6AR)-hydroxyhexahydrofuro[2,3-b]furan, a high-affinity non-peptidal ligand for HIV protease inhibitor UIC-94017, is described. The synthesis utilizes a novel stereoselective photochemical 1,3-dioxolane addition to 5(S)-benzyloxymethyl-2(5H)-furanone as the key step.

A route for the syntheses of Dibenzo[def,p]chrysene and its 12-methoxy derivative using a Suzuki cross-coupling approach is presented. This method is easy, gives high yields, and can be adapted to large scale synthesis.