Ligand-tagged liposomes, obtained by covalent conjugation of ligands to the liposomal surface, have been widely used as detection reagents in bioanalytical assays. A non-covalent conjugation method where IgG was attached to protein G-tagged liposomes has been recently utilized. To enlarge the application of non-covalent methods to a greater variety of ligands, including peptides, proteins, and nucleic acids, we developed and optimized a new method for the preparation of NeutrAvidin-tagged liposomes with subsequent attachment of biotinylated ligands.
View Article and Find Full Text PDFAttention to peanut allergy has been rising rapidly for the last 5 y, because it accounts for the majority of severe food-related anaphylaxis, it tends to appear early in life, and it usually is not resolved. Low milligram amounts of peanut allergens can induce severe allergic reactions in highly sensitized individuals, and no cure is available for peanut allergy. This review presents updated information on peanut allergy, peanut allergens (Ara h1 to h8), and available methods for detecting peanuts in foods.
View Article and Find Full Text PDFA competitive lateral flow assay for detecting the major peanut allergen, Ara h1, has been developed. The detector reagents are Ara h1-tagged liposomes, and the capture reagents are anti-Ara h1 polyclonal antibodies. Two types of rabbit polyclonal antibodies were raised either against the entire Ara h1 molecules (anti-Ara h1 Ab) or against an immunodominant epitope on Ara h1 (anti-peptide Ab).
View Article and Find Full Text PDFThe objective of this study was to develop and optimize a protocol for the rapid detection of Escherichia coli O157:H7 in aqueous samples by a combined immunomagnetic bead-immunoliposome (IMB/IL) fluorescence assay. The protocol consisted of the filtration or centrifugation of 30- to 100-ml samples followed by incubation of the filter membranes or pellet with anti-E. coli O157:H7 immunomagnetic beads in growth medium specific for E.
View Article and Find Full Text PDFAnal Bioanal Chem
January 2004
A rapid and highly sensitive receptor immunoassay for botulinum toxin (BT) has been developed using ganglioside-incorporated liposomes. Botulism outbreaks are relatively rare, but their results can be very severe, usually leading to death from respiratory failure. To exert their toxicity, the biological toxins must first bind to receptors on the cell surface, and the trisialoganglioside GT1b has been identified as the cell receptor for BT.
View Article and Find Full Text PDFAn extremely sensitive bioassay has been developed for cholera toxin (CT) detection, using ganglioside-incorporated liposomes. Cholera is a diarrheal disease, often associated with water or seafood contamination. Ganglioside GM1 was used to prepare the liposomes by spontaneous insertion into the phospholipid bilayer.
View Article and Find Full Text PDFNeuronal nicotinic acetylcholine receptors are members of the ligand-gated ion channel receptor superfamily and may play important roles in modulating neurotransmission, cognition, sensory gating, and anxiety. Because of its distribution and abundance in the CNS, the alpha 7 nicotinic receptor is a strong candidate to be involved in some of these functions. In this paper we describe the synthesis and in vitro profile of AR-R17779, (-)-spiro[1-azabicyclo[2.
View Article and Find Full Text PDFThe synthesis and antifungal activity of a series of novel 5-carbonyl derivatives of 3-phenyl-3-(1H-imidazol-1-ylmethyl)-2-methylisoxazolidines (4) are discussed. The preparation of the title compounds involved a 1,3-dipolar cycloaddition reaction of alpha-substituted ketonitrones with either acrylic esters, acrylamide or methyl vinyl ketone to furnish cis/trans-diastereomeric mixtures of the desired 5-carbonyl isoxazolidines 4. The anifungal activity was evaluated in vitro in solid agar cultures.
View Article and Find Full Text PDFThe synthesis and antifungal activity of a novel series of substituted 3,5-diphenyl-3-(1H-imidazol-1-ylmethyl)-2-alkylisoxazolidine derivatives (15-30) are described. The synthesis of the title compounds was accomplished via a 1,3-dipolar cycloaddition reaction of alpha-substituted ketonitrones with appropriate styrene precursors. The compounds when tested in vitro in solid agar cultures exerted a very potent antifungal activity against a wide variety of yeast and systemic mycoses and dermatophytes, especially Trichophyton and Microsporum sp.
View Article and Find Full Text PDFThe in vitro antifungal activity of a series of novel 5,5-disubstituted-3-phenyl-3-(1H-imidazol-1-ylmethyl)-2-methyli soxazolidines and related compounds against Trichophyton rubrum, Aspergillus fumigatus and Candida albicans was studied. The screening was performed in solid agar cultures and some structure-activity relationships involving the C-5-substitution pattern are discussed.
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