please help me in this regard as i have assayed the activity of alkaline phosphatase in IU/L in serum as the kit has mentioned the given unit while some research articles have mentioned the activity in mmol units.

my findings are 26.34 IU/Land the research articles that i have read have mentioned 0.347 mmol units.

my quires are

1.what is the similarity between the two units

2.how much 26.34 IU/L equals to ...mmol unit.

3.what is better to use for enzyme activity mmol units or IU/L.