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A pressurized liquid extraction-based method for the simultaneous extraction and in situ clean-up of polychlorinated biphenyls (PCBs), hydroxylated (OH)-PCBs and methylsulfonyl (MeSO(2))-PCBs from small (<0.5 g) tissue samples was developed and validated. Extraction of a laboratory reference material with hexane-dichloromethane-methanol (48:43:9, v/v) and(More)
[structure: see text] We have developed a general and efficient approach to a diverse series of phosphacoumarins as analogues of coumarins with various biological activities, and the inhibitory activity of the synthesized phosphacoumarins against the enzyme SHP-1, a protein tyrosine phosphatases, was tested. Some of them showed moderate to good efficiency.
Water-soluble organic nanoparticles were prepared by cross-linking the micelles of a tripropargylated cationic surfactant by a diazide cross-linker in the presence of Cu(I) catalysts. The nanoparticles were decorated with hydrophilic ligands of different lengths on the surface. By interacting with negatively charged liposomes through tunable electrostatic(More)
The micelles of two tripropargylammonium-functionalized cationic surfactants were cross-linked by a disulfide-containing diazido cross-linker in the presence of Cu(I) catalysts. With multiple residual alkyne groups on the surface, the resulting surface cross-linked micelles (SCMs) were postfunctionalized by reaction with 2-azidoethanol and an(More)
Polychlorinated biphenyls (PCBs), a major class of persistent organic pollutants, are metabolized to hydroxylated PCBs. Several hydroxylated PCBs are substrates of cytosolic phase II enzymes, such as phenol and hydroxysteroid (alcohol) sulfotransferases; however, the corresponding sulfation products have not been isolated and characterized. Here we describe(More)
Glutamate-functionalized oligocholate foldamers bound Zn(OAc)(2), guanidine, and even amine compounds with surprisingly high affinities. The conformational change of the hosts during binding was crucial to the enhanced binding affinity. The strongest cooperativity between the conformation and guest-binding occurred when the hosts were unfolded but near the(More)
A series of hydrocarbon and fluorocarbon carbohydrate surfactants with different headgroups (i.e., gluco-, galacto- and maltopyranoside) and (fluorinated) alkyl tails (i.e., C7 and C14 to C19) was synthesized to investigate trends in their cytotoxicity and haemolytic activity, and how surfactant-lipid interactions of selected surfactants contribute to these(More)
The disposition of toxicants is often affected by their binding to serum proteins, of which the most abundant in humans is serum albumin (HSA). There is increasing interest in the toxicities of environmentally persistent polychlorinated biphenyls (PCBs) with lower numbers of chlorine atoms (LC-PCBs) due to their presence in both indoor and outdoor air. PCB(More)
Three macrocyclic oligocholates containing a carboxyl group, a guanidinium ion, and a Cbz-protected amine, respectively, were studied as membrane transporters for hydrophilic molecules. To permeate glucose across lipid bilayers, the macrocycles stacked over one another to form a transmembrane nanopore, driven by a strong tendency of the water molecules in(More)
BACKGROUND Polychlorinated biphenyls are persistent organic pollutants that can be metabolized via hydroxylated PCBs to PCB sulfate metabolites. The sensitive and selective analysis of PCB sulfate monoesters by gas chromatography-mass spectrometry (GC-MS) requires their derivatization, for example, as PCB 2,2,2-trichloroethyl (TCE) sulfate monoesters. To(More)