Process for detecting binding reactions with use of the measurement of the relaxation of the double refraction of magnetic particles

Abstract

The invention relates to a new process for detecting analytes or binding reactions using measurement of the double refraction, as well as the use of the compounds in analytical chemistry that are necessary for this purpose.

1 - 18 . (Cancelled)  
     
     
         19 . A composition that comprises combinations of a ferromagnetic or ferrimagnetic substance with a structure-specific substance, wherein the structure-specific substance is such that its Brownian relaxation proceeds faster than its Néelian relaxation under measuring conditions for detection of an analyte or binding reaction by its double refraction behavior or relaxation behavior of double refraction in the composition.  
     
     
         20 . A composition that comprises combinations of a ferromagnetic or ferrimagnetic substance with a substance that is to be identified, wherein the substance that is to be identified is such that its Brownian relaxation proceeds faster than its Néelian relaxation under measuring conditions for detection of a binding reaction by its double refraction behavior or relaxation behavior of double refraction in the composition.  
     
     
         21 . A composition according to  claim 19 , wherein the ferromagnetic or ferrimagnetic substance's particle size is 1 nm to 100 μm.  
     
     
         22 . A composition according to  claim 19 , wherein the ferromagnetic or ferrimagnetic substance is stabilized with a shell that comprises an oligomeric or polymeric carbohydrate, protein, peptide, nucleotide, surfactant, polymer and/or lipid.  
     
     
         23 . A composition according to  claim 19 , wherein the structure-specific substance is an antibody, antibody fragment, biotin, a substance that binds biotin, agonist that binds specifically to receptors or their antagonists, peptide, protein, receptor, enzyme, enzyme substrate, nucleotide, ribonucleic acid, deoxyribonucleic acid, carbohydrate, or lipoprotein.  
     
     
         24 - 25 . (Cancelled)  
     
     
         26 . An apparatus comprising a light polarizer, a device that receives a sample, a device that magnetizes the sample with magnetic pulses or a magnetic field of variable frequency, and an analysis of analyzer that analyzes the polarization direction of polarized light, wherein said apparatus is capable of implementing a process for detecting an analyte or a binding reaction in a binding assay conducted in a sample labeled with a ferromagnetic or ferrimagnetic substance comprising determining double refraction behavior or relaxation behavior of double refraction in the sample, and correlating said behavior with the presence of the analyte or binding reaction.  
     
     
         27 . An apparatus according to  claim 26 , that contains an optical bank, a laser, a polarizer, an optical cell containing the sample, an analyzer and a photodetector.  
     
     
         28 . An apparatus according to  claim 26  further comprising a λ/4-plate between the sample and the analyzer.  
     
     
         29 . A composition according to  claim 20 , wherein the ferromagnetic or ferrimagnetic substance's particle size is 1 nm to 100 μm.  
     
     
         30 . A composition according to  claim 20 , wherein the ferromagnetic or ferrimagnetic substance is stabilized with a shell that comprises an oligomeric or polymeric carbohydrate, protein, peptide, nucleotide, surfactant, polymer and/or lipid.  
     
     
         31 . A composition according to  claim 20 , wherein the substance that is to be identified is an antibody, antibody fragment, biotin, a substance that binds biotin, agonist that binds specifically to receptors or their antagonists, peptide, protein, receptor, enzyme, enzyme substrate, nucleotide, ribonucleic acid, deoxyribonucleic acid, carbohydrate, or lipoprotein