Patent ID: 8263416
Filing Date: 2012-09-11
Classification: G01N

Abstract:
1. A method of turbidimetric immunoassay for assessing human Cystatin C in a human body liquid sample comprising a) forming an assay mixture by contacting said sample with a nanoparticle-antibody conjugate, comprising nanoparticles suitable for turbidimetric measurement, wherein said nanoparticles are coated with a shell of proteinaceous material comprising anti-human Cystatin C antibodies or antigen binding fragments thereof, to bind said Cystatin C, wherein said coated nanoparticles have a median diameter in the range of more than 58 up to 200 nm, and b) assessing the human Cystatin C content by measuring the change in turbidity of said mixture, wherein the coating is such that said nanoparticles are coated with about 5 to 35% of antibody binding to human Cystatin C per total weight of the nanoparticle-antibody conjugate.