3
Applications
Measure Custom
38
NanoDrop One
C
with NanoDropQC Software User Guide
Thermo Scientific
Factor or Extinction coeffi-
cient at 1 cm pathlength
(Formula methods only)
Specify whether to use factor or extinction coefficient to calculate concentration
result:
•
User-defined factor
. Enter
factor
for 1 cm pathlength and use adjacent drop
down list to select appropriate
unit
. Equation below shows how factor is used to
calculate sample concentration:
c = (A * f) / b
where:
c
= analyte concentration
A
= absorbance in absorbance units (A)
f
= factor (typically 1/
, where
= wavelength-dependent molar absorptivity
coefficient, or extinction coefficient)
b
= pathlength in cm (determined at measurement time, then normalized to
10 mm (1 cm) pathlength equivalent)
•
Extinction coefficient and molecular weight
. Enter
extinction coefficient
for
1 cm pathlength and use adjacent drop down list to select appropriate
unit
.
Equation below shows how extinction coefficient is used to calculate sample
concentration:
c = A / (
* b)
where:
c
= analyte concentration
A
= absorbance in absorbance units (A)
= wavelength-dependent molar absorptivity coefficient (or extinction
coefficient)
b
= pathlength in cm (determined at measurement time, then normalized to
10 mm (1 cm) pathlength equivalent)
Notes
:
• Refer to product literature for information about factors and extinction
coefficients for specific materials.
• To set up a method that reports absorbance measurements only, select Factor or
Extinction Coefficient with the factor or extinction coefficient set to “1”.
• If specified unit for factor or extinction coefficient is based on mass (such as
mg/mL) and specified unit for calculated result is based on molarity (such as
pmol/µL) or vice versa, enter
molecular weight
and use adjacent drop down list
to select appropriate
unit
.
Setting
Available Options
