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Convert DNase units to weight - 2mg/ml from a 2U/ml solution (Sep/16/2004 )

hello guys!

I need to prepare a 2 mg/mL DNAase solution. the DNAase stock has a concentration of 2U/ml. how can i make a 2mg/ml from a 2U/ml solution? this is quite hard to figure out .

hope very much for replies!

thanks for helping!


It hard to convert units to weight unless the vendor provides such information. Some vendors say one mg dry weigt of DNase I has >2,000 Kunitz units. Qiagen explicitily says that one mg = 2500 Kunitz units. If this is given, you can estimate the weight. However this number may not be applied to DNase from another vendor since they may have different activity.


hello labrat!

thanks for your helping, but still i can't figure out how to make a 2mg/ml from a 2U/ml, if for instance as your vendor said; 1 mg= 2500 Kunitz units. hope that you can show me the calculation. by the way what is Kunitz units? i am new about this, so hope that you can help me out!

thanks alot!


One Kunitz unit is defined as the amount of DNase I that causes an increase in A260 of 0.001 per minute per milliliter at 25°C, pH 5.0, with highly polymerized DNA as the substrate
One unit is the amount of the enzyme required to degrade 1 mg of calf thymus DNA in 10 minutes at 37°C completely. (1.5 units = 1 Kunitz unit)