This red powder is a dye that turns an intense yellow-green when mixed with water.
Fluorescein was first made in 1871 and it has since found use in many niche applications thanks to its unique coloring properties and ultraviolet fluorescence.
It is commonly used as a medical dye to detect and diagnose various eye injuries and also to trace the flow of streams, groundwater, and glacier water.
When mixing with water, a tiny amount goes a long way. This vial should be enough to dye at least 100 gallons of water. It is organic and harmless to the environment at these low concentrations.
The fluorescein reaction is pH-dependent. Once it has reacted in water, the color can be altered by changing the acidity of the water.
Even though fluorescein is commonly used in medical applications, please do not consume it.
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Vlad gave this item 5 stars
Charlie gave this item 5 stars
Item matched the description. A few tiny specs will make a liter of water glow bright green. Used it for a Halloween scientific glass display; it worked awesome and got lots of interest.
Fluorescein is very handy for finding leaks, among other purposes. A small amount goes a long ways. Glad I could get the amount I need at a decent price
This is pretty cool stuff
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