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Protein concentration for ext. coefficient - (Jul/20/2020 )

How can I determine the Protein concentration from its extinction coefficient. If the extinction coefficient is 14480. What will the procedure to determine its concentraion.

 

 

-samita-

A=ecl

 

A=absorbance

 

e=extinction coefficient

 

c=molar concentration

 

l=path length

 

rearranging to solve for c:

 

c=A/el

 

however, you can ignore l if it is the same for all measurements

 

therefore

 

molar concentration = absorbance/extinction coefficient

-mdfenko-

Thanks for your reply.

it will be molar concentration means Moles/litre (mM/ml and uM/uL) and to convert it into mg/ml we can simply multiple its molecular weight in daltons (grams/mole). The unit will be grams/lit (mg/ml and ug/uL). Will it be like this.

-samita-

Yes

-mdfenko-

Also, pay attention to the decimal point on absorbance readings (and on the extinction coefficient)

-mdfenko-