ThermoFisher Scientific NanoDrop Eight, User Manual

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4 Nucleic Acid Applications
Measure Oligo DNA or Oligo RNA
36 NanoDrop Eight User Guide Thermo Scientific
Related Topics
• Instrument Settings
Detection Limits for Oligo DNA and Oligo RNA Measurements
The lower detection limits and reproducibility specifications for the oligonucleotide
sample types (ssDNA and RNA) are provided
here . The upper detection limits are
dependent on the upper absorbance limit of the instrument and the extinction
coefficients for the user-defined base sequences.
To calculate upper detection limits for nucleic acid samples
To calculate upper detection limits in ng/µL, use the following equation:
(upper absorbance limit
instrumen
t
* extinction coefficient
sample
)
For example, for a sample measurement using an extinction coefficient of 55, the
equation looks like this:
(550 AU * 55 ng-cm/µL) = 30,250 ng/µL
• Molecular Weight of oligo calculated from user-defined
base sequence.
• Number of Bases entered.
• Molar Ext. Coefficient (260 nm) . Molar extinction
coefficient of oligo (in ng-cm/µL) at 260 nm calculated from
entered base sequence.
• %GC . Percentage of guanine and cytosine residues in
total number of bases entered.
Baseline
Correction On or off
Enter baseline
correction
wavelength in nm or
use default value
(340 nm)
Corrects for any offset caused by light scattering particulates
by subtracting measured absorbance at specified baseline
correction wavelength from absorbance values at all
wavelengths in sample spectrum. As a result, absorbance of
sample spectrum is zero at specified baseline correction
wavelength.
Tip : If the sample has a modification that absorbs light at
340 nm, select a different correction wavelength or turn off
Baseline Correction.
Setting Available Options Description
Note For measurements with 10 mm pathlength cuvettes, the upper
absorbance limit is 1.5 AU, which is approximately 75 ng/µL for dsDNA.