"drop of dye" is correct and usable in written English.
You can use it to describe a small amount of a colored liquid you would use for coloring something. For example, "She carefully added a drop of dye to the fabric to give it a hint of color."
Tracking the flow of wheat gluten around the world, much less evaluating its quality, is like trying to contain a drop of dye in a churning whirlpool.
A friend of mine once compared the presence of a lie in a piece of writing to a drop of dye in pure water.
"You can't see a nucleic acid or protein within a cell, so you have to use a drop of dye to bring out the structure.
I saw the first ash enter the air like a drop of dye in water, shooting forward then folding in on itself, expanding, losing definition, before being recharged with another burst.
Observations of an enhanced mass transfer and an irregular mixing when a small drop of dye is gently placed on a nanofluid dispersion have led to several propositions for the underlying cause, but none of them have been conclusively established.
Does one drop of dye in water really poison the whole glass?
After losing five straight games, the Nets (6-9) know this is not the time to dwell on negativity, something that could, like drops of dye, color the season.
Water flow rates were not measured directly, but drops of dye introduced into stirred water were completely dispersed (into the 70-ml volume) within 5 s.
The water was of course not completely still, as small temperature gradients led to some convective flow; however, flow rates were very low (and hence boundary layers around the egg mass very large); drops of dye put into still water took many minutes to disperse.
This comes out to about 4 to 5 drops of dye for each 1/4 cup of sugar.
Simply toss them into a bowl of water, to which you have added a few drops of dye.
