A researcher should be able to determine most definitively a

A researcher should be able to determine most definitively a solution containing single-stranded DNA from one containing double stranded DNA by

a. Heating the solutions to 90oC and then measuring the absorption of light at 260 nm

b. Monitoring the change in absorption of light at 260 nm while elevating the temperature

c. Determining the A260/A280 ratio for each sample.

d. Running an agarose gel on the samples and comparing their migration rates.

e. All of the above.

f. None of the above.

Solution

e. all of the above.

in general, absorbance at 260 nm is measured to check the substance. OD at 260 nm would be equal to 1, if the sample is 50 g/mL of dsDNA solution or 33 g/mL of ssDNA solution.

to check the purity ratio of absorbane at 260 nm to absorbance at 280 nm (A260/A280) is calcuated.

agarose gel electrophoresis can also be performed to differentiate. A supercoiled ds DNA would move faster on agarose gel compared to ssDNA.