Dear Kumar

Did you mean that you would like to calculathe the metal concent of a purifed metalloprotein sample and undestood for example if your protein bind 1 or 2 metal ions? 

Manuele

I'd recommend using the Bradford assay to measure your protein concentration.  Lowry and BCA are both metal dependent, so I'd avoid those assays.  Also, depending on the metal your protein contains, there may be an absorbance band that interferes with your ability to use a 280 nm absorbance reading.  However if the metal is something without charge transfer bands (ex. zinc) then measure your protein concentration by taking an absorbance measurement.

If you know the stoiochiometry of the metal to the protein (and there is no free metal), then the metal concentration in the protein sample determined by AAS can be used to calculate the protein concentration (in molar units) using the known stoichiometry. But it would be more direct to use a protein assay.

dear sir 

can you provide me with any paper or article related to the same.

Here is a paper on "metalloproteomics."

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3106322/

As a matter of fact, this is a classic experiment performed by Johann Friedrich Engelhart in 1825: He found that iron makes about 0.5% of haemoglobin irrespective of species and from the known atomic mass of iron (56) calculated the molecular mass of haemoglobin to n times 11000, with n the number of iron atoms per molecule of haemoglobin (which he had no way of knowing). Today we know the actual molecular mass is 4 times 16700, but given the primitive methods available to Engelhart his result is quite good. Scientists at that time believed this calculation to be "a hasty conclusion", and that no molecules could be that big. It took 100 years until Adair confirmed this result by osmotic pressure measurement.

I think i was not very clear about my question here, i want to know s it possible to calculate amount of protein in sample with help of AAS, if it is a metalloprotein?