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Equation for calculating insert:vector ratio in ligation reaction - (Feb/26/2009 )

hi all

i am very much in need for the equations to carry out calculations before performing ligation, can any one plz help?

-sagar-

Hey

Equations? calculations? for ligation?

I am not sure if I understand what you mean to convey.

TC

sagar on Feb 26 2009, 11:57 PM said:

hi all

i am very much in need for the equations to carry out calculations before performing ligation, can any one plz help?

-T C-

Do you need the ligation recipe or how to calculate the vector-insert ratio? Please be more specific.

-scolix-

insert mass in ng = 6 X (insert lenght in bp/vector lenght in bp) X vector mass in ng

You may change the 6 above depending on the actual ratio you want to get (sometimes a 3:1 works best than 6:1)

-planktonica-

planktonica on Mar 4 2009, 01:16 PM said:

insert mass in ng = 6 X (insert lenght in bp/vector lenght in bp) X vector mass in ng

You may change the 6 above depending on the actual ratio you want to get (sometimes a 3:1 works best than 6:1)


One thing to mention, you have to get pure vector and insert before applying this equation. Sometimes RNA contamination will lead to incorrect calculation.

Try 3:1 and 1:1 insert to vector ratio, these two ratio usually rock in ligation reaction.

-Nrelo-

Hi Sagar,

Go to the 'Biomath Calculator' website using the following link.

http://www.promega.com/biomath/default.htm

Click on Ligations: Molar Ratio of Insert to Vector

Enter the parameters of your ligation and it will calculate the relative amounts for you.

Easy! :P

-frg-