i want the caculation method for estimation of GST in serum
Here's a good article describing an assay for GST in serum.
Another one here.
i am already has a method but the way of calculation is a problem for me as i dilute the serum before the start and then dilute the final solution
can you be more specific how and when you dilute your samples? It would help greatly. Generally speaking, you have to take into account the _fold_ of dilution. For example, if you dilute your serum sample from 50 microliters to 150 microliters before the assay, the concentration is lower by three-fold, and hence you have to multiply the measured concentration by 3 to get the concentration in the original serum. I assume you dilute your original sample because the concentration is too high for the linear range of the assay, but why do you dilute your final solution?