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What are the limitations of Sudan IV test for lipid?
We just did a lab on this in my bio class.
The Sudan test uses Sudan IV reagent. If a lipid or fat is present, red globs of fat will appear at the top of the solution. If not, there won't be a...
Tests for lipids such as fats and oils based on their ability to selectively absorb pigments in fat-dyes such as the Sudan IV. The test will make red globs appear if it is indeed a lipid.
because it want to show that Sudan iv is soluble in water n not soluble when there is lipid presence . From there you can make lipid as your responding variable