This present invention provides rapid, reproducible, biomarker-based screening methods for the developmental toxicity testing of compounds. The methods are designed to identify the exposure level at which a test compound perturbs metabolism in a manner predictive of developmental toxicity. In particular, the perturbation of two metabolites, ornithine and cystine, is measured, wherein a ratio of the fold change in ornithine to the fold change in cystine of less than or equal to about 0.88 is indicative of the teratogenicity of a test compound.

Embodiments of compounds for selectively detecting an analyte are disclosed, along with methods and kits for detecting analytes with the compounds. The compounds are bridged viologen conjugates including at least one fluorophore according to the general structure ##STR00001## At least one of R.sup.1/R.sup.2, R.sup.2/R.sup.3, R.sup.3/R.sup.4, R.sup.5/R.sup.6, R.sup.6/R.sup.7, and/or R.sup.7/R.sup.8 together form a substituted or unsubstituted cycloalkyl or aryl.

Provided is a biosensing device including unit cells each including a source electrode and a drain electrode spaced apart from each other, a sensing membrane for forming a channel between the source and drain electrodes, a gate electrode spaced apart from the sensing membrane, and a dam structure surrounding at least parts of an edge of the sensing membrane and made of an insulator, wherein the dam structure is configured to contain a precursor solution to be solidified to generate the sensing membrane.

The Invention relates to a novel receptor molecule for estimation of amino acids based on florescence enhancements. Particularly, the invention relates to a novel Cu (II)-complex as a turn-on luminescence probe for selective detection of cysteine and histidine in pure aqueous environment and in biological sample as well as for detection of cyanide ions among various anions under physiological conditions.

The present invention relates to a compound (L) for selective determination of free cysteine and a process for the preparation thereof.

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wherein R1 is selected from benzene, toluene, naphthalene and pyrene.

The invention provides bioconjugates of heterocylic compounds such as S-adenosylmethionine and S-adenosylhomocysteine with biotin or digoxigenin. The bioconjugates also include carbon and nitrogen linker moieties of varying length that are used to attach such compounds to biotin or digoxigenin. The conjugates are useful in immunoassays. The invention provides a method for detecting SAM and SAH, comprising the steps of: (a) preparing the following components: (i) bio-conjugates of SAM, SAM analogs or SAH; (ii) an europium, a terbium cryptate or other fluorophore as a donor that has a specific ligand for the tracer in the bio-conjugates of (i); (iii) an acceptor fluorescent dye that has the excitation spectra overlap those of donor's emissions and has an antibody specific for SAM or SAH labeled; (b) addition of the biological fluid containing said SAM or SAH; and (c) spectroscopic measurement of the fluorescence of the donor and the fluorescence of from the acceptor.

The present invention includes: preparing a sample containing a peptide to be analyzed; adding a labeling compound which specifically reacts with a thiol group to the sample, and labeling a reduced cysteine residue contained in the peptide in the sample with the labeling compound; separating a sample containing the peptide labeled with the labeling compound by a chromatograph; executing product ion scan measurement with a peptide ion, as a precursor ion, generated by ionizing the peptide labeled with the labeling compound under a condition that a thiol group is not desorbed from a cysteine residue; and determining whether or not the peptide to be analyzed contains a reduced cysteine residue by determining whether or not a peak appearing at a specific mass-to-charge ratio corresponding to a structure of the labeling compound is present in a mass spectrum created based on data obtained by the measurement execution.

A facile laboratory-based method and kit for use in accordance with the method is disclosed. The method allows for the localisation of biomolecules comprising a conjugatable sulfhydryl group to be localised to the surface of cells, such as red blood cells, as lipid conjugates. The method obviates the need to purify the lipid-conjugated biomolecule before contacting with the cells.

The present invention, in some aspects, relates to systems and methods for determining oxidized proteins, including glutathionylated proteins such as S-glutathionylated proteins. The systems and methods of the invention can be used in vitro (e.g., in cell or tissue culture) or in vivo, for example, to diagnose a person having an oxidative stress condition. For instance, in some cases, the invention can be used to spatially determine the location and/or concentration of oxidized proteins within cells and/or tissues (e.g., through visual detection). In one set of embodiments, a glutathionylated or otherwise oxidized moiety on a protein may be reacted with a detection entity, which may be, for example, fluorescent, radioactive, electron-dense, able to bind to a signaling entity or a binding partner in order to produce a signal, etc. As a specific example, a glutathionylated moiety on a glutathionylated protein may be reacted with an alkylating agent to form an alkylthio moiety; the alkylthio moiety may include a detection entity or otherwise be able to interact with a signaling entity. In some embodiments, other moieties on the protein may be altered or blocked before reaction of the protein with the detection entity. Such moieties on the protein may be, for instance, non-oxidized or non-glutathionylated moieties able to react with the detection entity. As a particular example, in a protein containing a glutathionylated moiety and non-glutathionylated thiol moieties, the thiol moieties may first be altered or blocked prior to reaction of the protein with the detection entity. Also provided in certain aspects of the present invention are kits for determining oxidized proteins, which may include components such as detection entities, alkylating agents, blocking agents, reducing agents, signaling entities, binding partners, antibodies, instructions, and the like.

The present invention relates to a coumarin derivative of Formula (L) for detection of cysteine and process for preparation thereof. The present invention further relates to a process of detection of cysteine residues present in protein as well as the cysteine released by the enzymatic action of aminoacylase 1 by using coumarin derivative of Formula (L). ##STR00001##