Introduction：Colloidal gold diagnostic techniques are similar to ELISA assays and were initially used in serum and urine tests. The whole process of sample detection takes 5-10 min. Colloidal gold technology is an immunological detection method that medical researchers use colloidal gold instead of enzyme as a marker, on the basis of enzyme-labeled immunoassay, and antigen-antibody binding. It has made great contributions to the effective detection of AIDS virus in humans. With the in-depth development of medical technology, the application fields of immune colloidal gold technology are more extensive, such as pregnancy test and detection of various infectious diseases. At present, this technology is also widely used in veterinary clinical diagnosis.

Basic principle: Colloidal gold immunotechnology (GICT) is a labeling technology applied to antigen and antibody using colloidal gold as a tracer marker, which is a new technology in the field of immunology. With the continuous development of nanotechnology, colloidal gold has been discovered and widely used in various disciplines such as medicine, molecular science, biology and immunology. Colloidal gold refers to the polymerization of chloroauric acid (HAuCl4) into particles of a specific size under the action of reducing agents such as vitamin C and tannic acid, and these particles form stable colloidal substances under electrostatic action. The basic principle of colloidal gold technology: the microporous membrane is used as a carrier to coat a known antigen or antibody, and the sample to be tested is dropped through the diafiltration or capillary siphon effect of the microporous membrane. The antibody or antigen coated by the pore filter is combined, and then reacts with the colloidal gold marker to form a red line or point, which is positive, and no such phenomenon is negative.

Advantages: (1) The immunocolloidal gold diagnostic technology is easy to operate, only kits or test strips are required for detection, no other equipment and reagents are required, sample pretreatment is simple or unnecessary, samples are diverse, serum, tissue fluid, feces and urine liquid, etc. (2) Immunocolloidal gold diagnostic technology is convenient and fast, and the reaction generally only takes 5-10 minutes to produce results, while other methods, such as ELISSA, require 1-2 hours, and PCR takes the longest time. The technology is suitable for grassroots and on-site because it is convenient, fast and not constrained by the site. Rapidly specific without compromising sensitivity, with assays demonstrating sensitivity of 1ng/mL or less.The Colloidal Gold Pet Rapid Test Kit sold by FKNMED whose sensitivity can be reach up to 98% and

Specificity can be reach up to 97%. For further information, please click the link: https://www.fknmed.com/product/Colloidal-Gold-Pet-Rapid-Test-Kit-84.html (3) The use cost of immunocolloidal gold diagnostic technology is low, and the detection does not require special equipment and reagents. The judgment of the results is intuitive, and the negative and positive results have obvious color development, which is easy to judge by the naked eye. (4) Immunocolloidal gold diagnostic technology has specificity; it has a wide range of applications and can still be used under different detection conditions; it can detect multiple items at the same time, and improve the utilization rate of samples, especially when samples are difficult to obtain. Significantly. (5) The physical and chemical properties of colloidal gold labeling are stable, and the kits or test strips can be stored for a long time, and can be stored for more than 2 years under refrigerated conditions at 4oC without signal attenuation. (6) Since colloidal gold is red, it is not necessary to add coloring reagents, eliminating the need for enzyme-labeled carcinogenic substrates, reducing the harm to the test personnel and the pollution of the working environment, which is safe and environmentally friendly, and meets the requirements of building an environmentally friendly society.

Application: Due to the above advantages of immunocolloidal gold technology, it is widely used in veterinary clinical disease diagnosis, mainly including two aspects: one is for antibody detection, and the other is for disease detection. Antibody detection using immunocolloidal gold technology In the process of antibody detection, the basic principle of immunocolloidal gold diagnosis is that the corresponding antigen is coated on a nitrocellulose membrane (NC membrane), and the corresponding antigen is labeled with colloidal gold. If the test sample is positive, Then the antibody in the sample reacts with the antigen or gold-labeled antigen on the NC membrane, and red lines or dots appear. If the sample is negative, the above phenomenon does not appear. A large number of studies have proved that in the antibody detection of many diseases in animals, the application of immunocolloidal gold technology has better coincidence rate, sensitivity and specificity. It can be seen that colloidal gold diagnostic technology has high coincidence rate, sensitivity and specificity in animal disease diagnosis, and this technology has important application value in veterinary clinical diagnosis.

Summary: To sum up, the immunocolloidal gold diagnostic technology has the advantages of simple operation, convenience and quickness, low detection cost, high sample utilization rate, easy analysis and judgment of results, high detection rate, strong stability and specificity, etc. It is especially suitable for grass-roots, field It has broad application prospects in veterinary clinical diagnosis.

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