Precious Metal Elements
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Principles and Examples of Detection for In-Vitro Diagnostic Kits
When gold is in colloidal form (nanoparticles), it takes on a red coloring. This property has been used in the field of medicine recently in diagnostic kits.
Nano-sized gold colloids are used with in-vitro diagnostic kits (immunochromatography*1) that enable fast and simple, early detection during influenza and pregnancy testing, allergen detection, and detection of some forms of cancer and other diseases.
*1. Immunochromatography is an analytical method enabling fast and simple visual determination of the existence of antigens in a sample (blood, etc.) by using capillary action of porous media.
![“I’m a gold nanocolloid, one-millionth of a millimeter in size. Nano-sized particles like me are not gold colored anymore, but wine-red colored.”“In-vitro diagnostic kits have taken advantage of this characteristic of mine.”](https://prod-cms-cache-bucket.s3-ap-northeast-1.amazonaws.com/wp-content/uploads/sites/images/ex/en/library/element/column01/images/img_block01_01.jpg)