Measure Proteins and Labels
Thermo Scientific NanoDrop One User Guide 75
Setting Available Options
Mass Ext. Coefficient
(L/gm-cm)
Description
Sample type
a
a
To add or edit a custom protein, use Protein Editor.
1 Abs = 1 mg/mL
BSA
IgG
Lysozyme
Other protein
(
+ MW)
Other protein
(
1%)
General reference
6.67
13.7
26.4
user-entered molar
extinction
coefficient/molecular
weight
User entered mass
extinction coefficient
Tap h ere for detailed description of each available setting.
Each sample type applies a unique extinction coefficient to
the protein calculations. If the extinction coefficient of the
sample is known, choose the
+ MW (molar) or 1%
(mass) option and enter the value. Otherwise, calculate the
extinction coefficient or choose the option that best
matches the sample solution. If you only need a rough
estimate of protein concentration and the sample extinction
coefficient is unknown, select the 1 Abs=1 mg/mL sample
type option.
Tip: Ideally, the extinction coefficient should be
determined empirically using a solution of the study
protein at a known concentration using the same buffer.
Analysis
Correction
b
b
Analysis Correction affects calculation for protein concentration only.
On or off
Enter analysis correction
wavelength in nm or use
default value (340 nm)
N/A Corrects sample absorbance measurement for any offset
caused by light scattering particulates by subtracting
absorbance value at specified analysis correction wavelength
from absorbance value at analysis wavelength. Corrected
value is used to calculate sample concentration.
Tip: If the sample has a modification that absorbs light at
340 nm, select a different correction wavelength or turn off
Analysis Correction.
Dye 1/Dye 2
Type
c
c
To add custom dye or edit list of available dyes, use Dye/Chromophore Editor.
Cy3, 5, 3.5, or 5.5,
Alexa Fluor 488, 546,
555, 594, 647, or 660
See
Dye/Chromophore
Editor for specific
values for each dye
Select pre-defined dye used to label sample material, or one
that has been added using Dye/Chrom. Editor.
Dye 1/Dye 2
Unit
picomoles/microliter
(pmol/uL), micromoles
(uM), or millimoles
(mM)
not applicable Select unit for reporting dye concentrations.
Sloping Dye
Correction
d
d
Sloping Dye Correction affects calculations for dye concentration only.
On or off Corrects dye absorbance measurements for any offset
caused by light scattering particulates by subtracting
absorbance value of a sloping baseline from 400 nm to
750 nm from absorbance value at dye’s analysis wavelength.