Tanaka Precious Metals has succeeded in developing a high-sensitivity in-vitro diagnostic kit which uses colloidal gold. This development was based on research by Professor Eiichi Tamiya of the Graduate School of Engineering at Osaka University. The newly developed diagnostic kit is an immunochromatographic diagnostic kit utilizing color phenomenon which is caused by plasmon effect ( a phenomenon in which the free electrons in a metal and incident light resonate on the surface of metal nanoparticles, causing colloidal gold to appear red) of colloidal gold in providing greater sensitivity tan existing diagnostic agents. The kit also limits reactions with substances other than targeted antigen and maintains a high level of sensitivity in case of using whole blood as specimen. This new technology is expected to be used for early detection of diseases requiring a high level of sensitivity such as prostate cancer.
Conventional primary screening in early diagnostic uses ELISA test as the enzymatic method, however, ELISA test result takes over 3 hours. The immunochromatography on the other hand is simple and fast but lack the sensitivity to be used as an early detection in clinical tests of positive family history and recurrence test, forcing the doctors to use it only for examination and primary screening. The new technology is able to detect PSA in concentrations of 0.2ng/ml which is required for the clinical test of positive family history and recurrence test of prostate cancer.
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