Ssdna calci

ssDNA concentration calculation

1. Calculation of ssDNA
Concentration
DR. S. SIVASANKARA NARAYANI., M.SC., M.PHIL.,PH.D.,MRSB(UK)
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2. Single-strandeddna(ssdna)concentrationexpressedinµg/ml
To determine the concentration of single-stranded DNA (ssDNA) as a µg/ mL
amount, the following conversion factor is used:
1 OD of ssDNA = 33 µg/mL
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3. Single-strandedDNAisolatedfromM13mp18,aderivativeofbacteriophageM13usedin
cloningandDNAsequencingapplications,isdiluted10µLintoatotalvolumeof1000µL
water.Theabsorbanceofthisdilutedsampleisreadat260nmandanA
260valueof0.125is
obtained.Whatisitsconcentrationinµg/mL?
1 OD = 33 µg/mL
0.125 OD = x µg/mL ?
x µg/mL = 0.125 OD X 33 µg/mL
= 4.125 µg/mL
Therefore, the concentration of the diluted sample is 4.125 µg/mL
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4. To determine the concentration of the M13mp18 DNA stock solution, this value must be
multiplied by the dilution factor:
4.125 µg/mL X 1000µl/10µl = 4125 µg/mL /10
= 412.5 µg/mL
Therefore, the stock of M13mp18 DNA has a concentration of 412.5 µg/mL.
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5. Reference
Calculations for molecular biology and Biotechnology –A Guide to
mathematics in the laboratory, Second Edition –Frank. H. Stephenson
[email protected]
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