Question

You have an RNA sample with a concentration of 23ng/ ul, the RT-qPCR protocol you are following states to use 75 ng of RNA per each reaction. What volume of your RNA sample will you need to obtain 75ng of RNA in one reaction?

Answer 1

Answer and Explanation:

Here from the data in this question, the concentration of RNA in sample is 23 ng/ul and the required concentration is 75 ng. Since the stock concentration is low, we don't have to dilute the RNA.

1 ul have 23 ng and 3 ul will have 69 ng (3 x 23). 4ul will have concentration of 92. We need 6 more ng apart from 3 ul having 69 ng.

1 ul has 23 ng, 0.5 ul has 11.5 ng, 0.25 ul will have 5.75 ng. 0.26 ul will have approximately 6 ng.

So 3 ul with 69 ng + 0.26 ul with 6 ng = 3.26 ul of RNA is needed to get 75 ng in approximate.

It is approximate we cannot take exactly the 75 ng.