I am working with a 12 KDa protein overexpressed in E.coli and want to detect the amount of calcium bound to the protein sample by AAS. So please suggest.
AAS is used to detect heavy metal while flame photometer is used to detect calcium (alkaline earth metals). you can detect Ca in yr sample by using bi acidic digestion method followed by analysis through flame photometer
Add 10 ml of concentrated nitric acid of high purity, digest your samples in microwave oven and dilute further if necessary with deionised water. Then use FAAS to determine calcium in your samples.