5 replies to this topic

[Mad Researcher]

Hi,

I am confused as how to calculate the activity of Papain. 

It's in lyophilized form and I want to prepare 200 µl. So, how can I calculate the activity.

I have the following information: Size - 1 u/vial and Act: 26.1 u/mgP; 57% protein

 

What should I dissolve it in to prepare the solution?

 

Thanks

[bob1]

Do you have an activity that you want? Or do you want activity per ul? 

 

If the latter, then it is simple 1 U/200 ul = 0.005 U/ul

[Mad Researcher]

Do you have an activity that you want? Or do you want activity per ul? 

 

If the latter, then it is simple 1 U/200 ul = 0.005 U/ul

Hi Bob,

I want an activity of 20 units/ml. How do I calculate that?

[bob1]

200 ul is 0.2 of a ml. 

 

For this you can use the n=c*v

 

n= 20 u/ml * 0.2 ml

n=4 U

[Mad Researcher]

200 ul is 0.2 of a ml. 

 

For this you can use the n=c*v

 

n= 20 u/ml * 0.2 ml

n=4 U

So, how much of the solution (example, PBS) should I add to the lyophilized powder to make it 4U? Also, is PBS is the best solution to dissolve the Papain or do you recommend dissolving it in any other solution?

[bob1]

Your vial contains 1 U total... so you would add 1/20th of a ml or 50 ul. You can not make a 200 ul solution with a concentration of 20 U/ml with this vial alone.