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SECTION 9 – DNA/PROTEIN
The DNA/Protein measurement mode allows the user to measure multi-wavelength absorbance
ratios, such as 260nm/280nm and 260nm/230nm, which are commonly used to estimate a protein or
nucleic acid sample’s purity. The mode also includes calculations that can be used to estimate the
concentration of the protein or nucleic acid sample.
9.1
DNA MENU OPTIONS
The
DNA/Protein measurement mode enables
measurement parameters to be changed. The four
options at the bottom of the screen allow the user to edit
the concentration calculation factors, select the
measurement mode, select the units of the
measurement and reset the modes settings to their
default values. These options are selected with the
corresponding function buttons.
9.2
ADJUSTING THE MEASUREMENT MODE
The DNA/Protein measurement mode includes two sets
of calculations to calculate the concentration of nucleic
acid and protein samples. The measurement mode
option can be selected by pressing the function key
below the Mode option. The options that are available
are:-
1. Absorbance Difference 1
2. Absorbance Difference 2
The default equations and factors used by the
instrument are shown below:-
Absorbance Difference 1
Purity Ratio = Abs@260nm / Abs@280nm
DNA Conc ( g/ml) = (Abs@
260
x 62.9) – (Abs@
280
x 36.0)
Protein Conc ( g/ml) = (Abs@280 x 1553) – (Abs@260 x
757.3)
