spectrophotometric analysis - (Apr/18/2007 )

hey there...

can someone pls help me with this question...i read it and I dont understand a word of it...

a newly-isolated dna sample had an absorbance@260 of 0.8 for a 0.02mg.ml-1 soln. when 1ml of this soln was mixed with 1ml of 0.5M HCl and hydrolysed for 6hr, the resulting soln had an absorbance@260 of 0.53. if the original soln (0.02mg.ml-1) was heated to 100 degrees celsius for 5min and then quickly cooled wat absorbance@260 wld you expect to measure at a 1 in 5 dilation...

can someone pls explain the steps (not the answer) for dng this problem...

cheers
biology_06er

so you have to think about what the steps would do to the DNA. you understand that mg.ml-1 is mg/ml right? and the standard you should be using is listed as X ug per A260 unit. You should have this number available to you or it would be easy to look up so I won't give it here. When you find that constant you will find it describes different X ug for different "types" of DNA then you think about what the treatments given above will do to the DNA and use the appropriate constant. Hint: remember to pay attention to the treatment some of these treatments listed will dilute the final concentration others will not.

If you post what you come up with I will check your work.

good luck!