If 633 mCi are expected to be eluted from a wet column generator, what volume of evacuated vial should be used to obtain an eluate concentration of approximately 30 mCi/ml?

To determine the appropriate volume of the evacuated vial in order to achieve an eluate concentration of approximately 30 mCi/ml from a total activity of 633 mCi, a simple calculation can be employed. The desired concentration can be formulated as the total radioactivity divided by the volume.

By rearranging this formula, the required volume can be calculated as:

Volume (ml) = Total Activity (mCi) / Required Concentration (mCi/ml)

Substituting the values:

Volume (ml) = 633 mCi / 30 mCi/ml = 21.1 ml

This calculation demonstrates that using a volume of 21.1 ml would yield the expected concentration of approximately 30 mCi/ml when starting with an activity of 633 mCi.

Choosing a different volume would result in either a concentration that is too high or too low compared to the desired 30 mCi/ml. For example, selecting a larger volume like 25.0 or 30.0 ml would dilute the eluate more than needed, while a smaller volume such as 15.5 ml would concentrate the activity higher than 30 mCi/ml. Thus, the choice of 21.1 ml is optimal to meet the