Question

ou are given an oligonucleotide whose molecular weight is 10000 dalton. assuming you want to make 100micro litre of 100micro molar stock. how much oligonucleotide you would need? ​

Answer 1

Given info : You are given an oligonucleotide whose molecular weight is 10000 Daltons. Assuming you want to make 100 µl of 100 µM stock.

To find : how much oligonucleotide would you need ?

solution : molecular weight of oligonucleotide = 10000 Daltons.

we know, 1 Dalton = 1 amu [ approx ]

so, molecular weight of oligonucleotide = 10000 amu = 10000 g/mol.

volume of solution = 100 μL = 10¯⁴ L

molarity of solution = 100 μM = 10¯⁴ M

we know,

molarity = mole of solute/volume of solution

⇒10¯⁴ M = mole of solute/10¯⁴ L

⇒mole of solute = 10^-8

mass of oligonucleotide/molecular weight of oligonucleotide = 10^-8

⇒mass of oligonucleotide/10000 = 10^-8

⇒mass of oligonucleotide = 10¯⁴ g = 100 × 10¯⁶ g = 100μg

Therefore the mass of oligonucleotide is 100μg