Table of Contents
Advertisement
7
Custom Applications
Measure Custom
Setting
Analysis wavelength
correction
Factor or Extinction coeffi-
cient at 1 cm pathlength
(Formula methods only)
162
NanoDrop One User Guide
Available Options
Use this option to specify absorbance correction at analysis wavelength only.
Available options:
• None. No correction at analysis wavelength.
• Single point. Enter wavelength for analysis correction. (Absorbance
value at specified analysis correction wavelength is subtracted from
absorbance value at analysis wavelength. Corrected value is used to
calculate sample concentration.)
• Sloping baseline. Enter two wavelengths that define sloping baseline
for analysis correction. (Absorbance value of sloping baseline at analysis
wavelength is subtracted from absorbance value at analysis wavelength.
Corrected value is used to calculate sample concentration.)
Specify whether to use factor or extinction coefficient to calculate concentra-
tion 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/
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)
, where
= wavelength-dependent molar
Thermo Scientific
Advertisement
Table of Contents
