Protein Concerntrations - Protein Concerntrations Using a Spectrophtometer (Dec/06/2008 )

Hi Guys......

Can somebody explain briefly to me about:

How to measure protein concerntrations using a spectrophotometer?, as we know that proteins are colorless, so these protein are found in the urine of some ill patients....please help me...giving some respond or sugestions.

Thanks!

For total protein the biuret test is suitable
http://en.wikipedia.org/wiki/Biuret_test