Chemistry: analytical and immunological testing – Involving immune complex formed in liquid phase
Patent
1997-12-22
2000-08-15
Chin, Christopher L.
Chemistry: analytical and immunological testing
Involving immune complex formed in liquid phase
435 71, 435 792, 435 793, 435 794, 435 795, 435962, 436518, 436523, 436524, 436526, 436534, 436537, 436176, 436826, G01N 33533
Patent
active
061035386
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates to an improvement in a colloidal gold immunoassay method for the determination of the presence or absence or the degree of presence of a target substance in a specimen, and especially to an improvement in a colloidal gold immunoassay method useful in the field of external diagnostics.
BACKGROUND ART
Detection of an antigen or an antibody by a colloidal gold immunoassay method is known for many years. The principle of this assay method is summarized as set out next. Namely, when a target substance is an antigen, for example, a colloidal gold which has been sensitized with an antibody capable of recognizing this antigen, that is, an antibody-sensitized colloidal gold is used in a reaction mixture containing, in general, the antigen and impurities and the like in an intimately mixed state, whereby the antibody-sensitized colloidal gold is specifically caused to bind to the antigen. A complex-containing reaction mixture, which contains a complex formed as a result of the reaction, is subjected to permeation like chromatographic development through a reaction mixture permeable material or to filtering permeation through a reaction mixture permeable material while making use of a diffusive infiltration phenomenon of the reaction mixture, so that the reaction mixture containing the complex, the antibody-sensitized colloidal gold, which has not reacted, and the impurities and the like are allowed to infiltratively move.
Further, by a capturing antibody which has been immobilized beforehand on the reaction mixture permeable material at a specific position on a moving path, binds specifically to the antigen and is different in antigen recognition site from the antibody-sensitized colloidal gold, the complex alone is captured at the specific position and the remaining matters are moved away along with the reaction mixture. By a color tone of the colloidal gold in the complex as appeared at the specific position, the antigen alone is distinguished or detected.
When the target is an antibody, on the other hand, a colloidal gold which has been sensitized with an antigen capable of recognizing the antibody (antigen-sensitized colloidal gold) is also reacted with the antibody by specific binding in a reaction mixture containing the antibody. Subsequently, the complex-containing reaction mixture which contains the resulting complex is caused to move through a reaction mixture permeable material by making use of a penetrative infiltration phenomenon as in the above-described detection. By either a capturing antibody or a capturing antigen which has been immobilized beforehand on the reaction mixture permeable material at a specific position and binds specifically to the antigen or antibody in the complex, only the complex out of the complex-containing reaction mixture is captured at the specific position. By a color tone of the colloidal gold in the complex as appeared at the specific position, the target antibody alone can be distinguished or detected.
In this colloidal gold immunoassay method, the specific binding is generally binding through an antigen-antibody reaction, and a usable colloidal gold is generally of the red type or the purple type.
The reaction mixture generally contains, as a medium, water which in turn contains biocomponents, buffer and the like. Water may be replaced in part by an inert water-soluble organic solvent such as dimethyl sulfoxide or dioxane with a view to assisting dissolution of the target substance in such a liquid-form medium, namely, liquid medium without interfering with the specific binding reaction. Further, an inert high-molecular substance may be added to protect the antibody or the like or to lower the dielectric constant of the reaction mixture containing the colloidal gold. Moreover, a surface active substance or the like can also be added for assisting the diffusive infiltration phenomenon of the reaction mixture.
As the reaction mixture permeable material, a sheet-like or laminate-like material equipped with permeability for the react
REFERENCES:
patent: 5108933 (1992-04-01), Liberti et al.
patent: 5225326 (1993-07-01), Bresser et al.
Chin Christopher L.
Nguyen Bao-Thuy L.
SS Pharmaceutical Co., Ltd.
LandOfFree
Colloidal gold immunoassay method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Colloidal gold immunoassay method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Colloidal gold immunoassay method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2005592