Patent ID: 8399260
Filing Date: 2013-03-19
Classification: C07K,G01N,Y10T

Abstract:
1. A method for extracting low-molecular-weight proteins/peptides contained in a body fluid sample, the method comprising the steps of: (a) adding reagent 1 containing urea and thiourea and reagent 2 containing a reducing agent to the body fluid sample, mixing reagent 1, reagent 2 and the body fluid sample to form mixture 1, subsequently dropping the mixture 1 into reagent 3 containing 95% or more of an organic solvent, and mixing the mixture 1 and reagent 3 to form mixture 2, wherein a volume of reagent 3 used in the dropping is 20 times or more of the mixture 1; (b) stirring at a temperature ranging from −20 to 10° C. the mixture 2 obtained in step (a); (c) centrifuging at a temperature ranging from 0 to 10° C. the stirred solution obtained in step (b) and removing the supernatant; (d) adding reagent 4 containing an organic solvent and an acid to the precipitate obtained in step (c) and mixing reagent 4 and the precipitate; (e) stirring at a temperature ranging from −20 to 10° C. the mixed solution obtained in step (d); and (f) centrifuging at a temperature ranging from 0 to 10° C. the stirred solution obtained in step (e) and recovering the supernatant.