Abstract: The present disclosure relates to novel bis-maleic anhydrides and to the surprising discovery that bis-maleic anhydride cross-linking agents can be used for preservation/fixation of a cell or tissue sample. Various bis-maleic anhydride cross-linking agent scan be used in methods requiring fixation of a cell or tissue sample. These reagents and methods are especially useful in procedures that require that the fixation agent be removed in order to facilitate analysis with other reagents. The inventive reagents and methods make it easier to reliably assay for various proteins, a nucleic acid and the like using analytical methods such as like immunohistochemistry, fluorescence in situ hybridization, RT-PCR, and the like.

Abstract: Disclosed are pyridinyl-isoquinoline-dione derivatives, methods of producing these derivatives, conjugates comprising the pyridinyl-isoquinoline dione derivatives and (i) a solid support, or (ii) a biomolecule, methods of producing these conjugates as well as the use of these conjugates as quenchers in fluorescence resonance energy transfer (FRET).

Abstract: The present disclosure relates to novel bis-maleic anhydrides and to the surprising discovery that bis-maleic anhydride cross-linking agents can be used for preservation/fixation of a cell or tissue sample. Various bis-maleic anhydride cross-linking agent scan be used in methods requiring fixation of a cell or tissue sample. These reagents and methods are especially useful in procedures that require that the fixation agent be removed in order to facilitate analysis with other reagents. The inventive reagents and methods make it easier to reliably assay for various proteins, a nucleic acid and the like using analytical methods such as like immunohistochemistry, fluorescence in situ hybridization, RT-PCR, and the like.

Abstract: The present invention relates to a method of measuring a vitamin D metabolite in a sample, the method comprising the steps of (a) treating said sample with a vitamin D metabolite releasing reagent under conditions appropriate to release a vitamin D metabolite from vitamin D-binding protein and not to cause protein precipitation, (b) subjecting the treated sample obtained in step (a) to a chromatographic separation, and (c) measuring a vitamin D metabolite during or after said chromatographic separation. The present invention also relates to methods for determining the vitamin D status of a subject, for use in the diagnosis of disease, and to agents and kits for use in performing the methods of the invention.

Abstract: The invention relates to a method for differentially hemolyzing whole blood. It discloses methods for detecting an analyte in a liquid sample known or suspected to contain red blood cells and suspected or known to contain eukaryotic cells, the method including the steps of processing the liquid sample with a membrane solubilizing agent under conditions appropriate to lyse cell membranes of red blood cells and at the same time not to cause precipitation of sample constituents, subjecting the processed sample to a chromatographic separation, and detecting the analyte. The differential hemolysis of red blood cells is of advantage in a method of detecting an analyte in a liquid sample that may contain both erythrocytes and nucleated cells. The differential solubilization of red blood cells can be easily combined with an online detection methodology, like LC-MS, and is advantageous in the detection of many analytes, e.g. in the detection of folate or of immunosuppressive drugs, like tacrolimus or sirolimus.

Abstract: Disclosed are pyridinyl-isoquinoline-dione derivatives, methods of producing these derivatives, conjugates comprising the pyridinyl-isoquinoline dione derivatives and (i) a solid support, or (ii) a biomolecule, methods of producing these conjugates as well as the use of these conjugates as quenchers in fluorescence resonance energy transfer (FRET).

Abstract: The present invention relates to a sampling tube for collecting and processing a whole blood sample. The sampling tube contains a reagent for differential hemolysis of whole blood, wherein said reagent for differential hemolysis comprises a chemical for differential hemolysis and an anti-coagulant, and wherein said sampling tube is a ready-to-use and single-use sampling tube. It also relates to the use of said sampling tube in the processing of a whole blood sample for liquid chromatography and also to the use of a blood sample processed in such sampling tube in a liquid chromatography-based analysis.

Abstract: The present invention relates to a method of measuring a vitamin D metabolite in a sample, the method comprising the steps of (a) treating said sample with a vitamin D metabolite releasing reagent under conditions appropriate to release a vitamin D metabolite from vitamin D-binding protein and not to cause protein precipitation, (b) subjecting the treated sample obtained in step (a) to a chromatographic separation, and (c) measuring a vitamin D metabolite during or after said chromatographic separation. The present invention also relates to methods for determining the vitamin D status of a subject, for use in the diagnosis of disease, and to agents and kits for use in performing the methods of the invention.

Abstract: The present invention provides a novel procedure of preparing samples for analysis by way of mass spectrometry, preferably LC-MS/MS. Accordingly, functionalized magnetic particles with a hydrophobic surface were used for extracting low molecular weight compounds from complex liquid biological samples such as plasma, serum, whole blood or hemolyzed blood. The method of the invention includes (a) contacting the sample with an amount of functionalized magnetic particles with a hydrophobic surface, (b) incubating the sample and the particles, thereby adsorbing the compound to the hydrophobic surface, (c) separating the particles by applying a magnetic field and removing the liquid, (d) optionally washing the particles, (e) eluting the compound from the particles.

Abstract: The present invention relates to a reagent for digestion of hemoglobin comprising a buffer, pepsin and a 1,3-dialkyl-imidazolium salt. It also discloses to the use of this reagent in a method for digesting hemoglobin, in a method for detecting HbA1c, and to a sampling tube for collection of a whole blood sample comprising said reagent for digesting hemoglobin.

Abstract: A method and reagent for detecting the presence or amount of an analyte by a redox reaction and a fluorimetric determination, is disclosed. The reagent comprises a compound of the general formula Q-F as a redox indicator, wherein Q is a quencher group and F is a fluorophore group. The quencher group Q or/and the fluorophore group F can be reduced or oxidized, and the fluorescence can change depending on the reduction or oxidation.

Abstract: The present invention relates to novel chemiluminescent compounds, to a method for synthesizing these compounds, to derivatives and conjugates comprising these compounds, to the use of these compounds or conjugates thereof in chemiluminescence based assays, especially in immunoassays.

Abstract: Disclosed herein are branched linkers of the formula: Zn-Y-Xm Wherein X, Y, Z, m, and n are as defined herein. The branched linkers are useful for producing conjugates that are used in diagnostic or therapeutic methods. Methods of producing the branched linkers are also described.

Abstract: The invention relates to a method for differentially hemolyzing whole blood. It discloses method for detecting an analyte in a liquid sample known or suspected to comprise red blood cells and suspected or known to comprise eukaryotic cells, the method comprising the steps of processing said liquid sample with a membrane solubilizing agent under conditions appropriate to lyse cell membranes of red blood cells and at the same time not to cause precipitation of sample constituents, subjecting the processed sample to a chromatographic separation, and detecting the analyte. The differential hemolysis of red blood cells is of advantage in a method of detecting an analyte in a liquid sample that may comprise both erythrocytes as well as nucleated cells. The differential solubilization of red blood cells can be easily combined with an online detection methodology, like LC-MS, and is advantageous in the detection of many analytes, e.g.

Abstract: The present invention relates to a sampling tube for collecting and processing a whole blood sample. The sampling tube contains a reagent for differential hemolysis of whole blood, wherein said reagent for differential hemolysis comprises a chemical for differential hemolysis and an anti-coagulant, and wherein said sampling tube is a ready-to-use and single-use sampling tube. It also relates to the use of said sampling tube in the processing of a whole blood sample for liquid chromatography and also to the use of a blood sample processed in such sampling tube in a liquid chromatography-based analysis.

Abstract: The present invention relates to novel chemiluminescent compounds, to a method for synthesizing these compounds, to derivatives and conjugates comprising these compounds, to the use of these compounds or conjugates thereof in chemiluminescence based assays, especially in immunoassays.

Abstract: The present invention provides a novel procedure of preparing samples for analysis by way of mass spectrometry, preferably LC-MS/MS. Accordingly, functionalized magnetic particles with a hydrophobic surface were used for extracting low molecular weight compounds from complex liquid biological samples such as plasma, serum, whole blood or hemolyzed blood. The method of the invention includes (a) contacting the sample with an amount of functionalized magnetic particles with a hydrophobic surface, (b) incubating the sample and the particles, thereby adsorbing the compound to the hydrophobic surface, (c) separating the particles by applying a magnetic field and removing the liquid, (d) optionally washing the particles, (e) eluting the compound from the particles.

Abstract: A method and reagent for detecting the presence or amount of an analyte by a redox reaction and a fluorimetric determination, is disclosed. The reagent comprises a compound of the general formula Q-F as a redox indicator, wherein Q is a quencher group and F is a fluorophore group. The quencher group Q or/and the fluorophore group F can be reduced or oxidized, and the fluorescence can change depending on the reduction or oxidation.

Abstract: A method and reagent for detecting an analyte by a redox reaction and a fluorimetric determination, is disclosed. The method comprises contacting a sample containing the analyte with a detection reagent which contains a compound of the general formula Q-F as a fluorimetric redox indicator, wherein Q is a quencher group and F is a fluorophore group.

Abstract: The present invention concerns a method for producing microparticles loaded with proteins which is characterized in that the microparticles are loaded in suspension under strongly alkaline conditions. The invention also concerns microparticles which can be produced using this method and their use in a binding test e.g. in an immunoassay.