Test for Proteins

[KathChem82]

Please share with me your ideas about these tests! i believe they are tests for proteins. i just want to know the observable changes for positive results. if you can share with me the reactions, then it would be greatly appreciated.

1. Biuret Test
2. Ninhydrin Test
3. Xanthoproteic test
4. Millon's Test
5. Hopkins Cole test
6. Sakaguchi Test
7. Lead Acetate Test

Thanks Guys!