Operating Manual
16
1300-87076-1A Rev. 1
4. Open the detection arm and turn the pathlength selector to the appropriate position. For example, the
dsDNA concentration range of 0.5 mm is from 2 to 1,500 ng/µL, and 0.05 mm is from 1,000 to 20,000 ng/µL.
All method ranges are shown on the Spex NanoSNAP screen.
5. Add appropriate solution of at least 1 µL and tap on the
Blank
icon to establish blank data.
6. Tap on the
Name
bar to insert the sample name (optional). The naming system is auto-numbering.
7. Wipe away the blank solution off the sample window and the cover window with a lint-free wipe.
8. Add your sample of at least 1 µL and tap on the
Measure
icon for sample measurement.
9. Clean the sample window and cover on the detection arm with a lint-free wipe after the experiment. Use
deionized water, ethanol or isopropanol if needed.
10. The
Baseline correction
(340 nm) function is optional, and can be turned on/off any time.
11. The default of the
Auto Run
function is off. If
Auto Run
is turned on, sample measurement will be
performed automatically after closing the detection arm.
Note
: In Nucleic Acid, dsDNA, RNA, and ssDNA applications are offered in this protocol. If you need to test other
samples, please use
Factor Method
to customize your protocol settings in
More Assays
. Blank is not allowed to
be used for sample naming.
4.3 Calculation
In the nucleic acid protocols, a modified Beer-Lambert equation is used to calculate concentrations with
absorbance and factor as follows, with or without baseline correction.
Without baseline correction
: c = A260 x ԑ / b
With baseline correction
: c = (A260 - A
Baseline
) x ԑ / b
c
the nucleic acid concentration in ng/µL
A260 the absorbance at 260 nm
A
Baseline
absorbance at baseline wavelength
ԑ
the extinction coefficient factor of nucleic acid in ng x cm/µL
b
the pathlength in cm
The general extinction coefficient factors used in the calculation of nucleic acid are shown in Table 9.
Table 9. Extinction coefficient factors of nucleic acids.
Type
Extinction Coefficient Factors
dsDNA
50 ng x cm/µL
RNA
40 ng x cm/µL
ssDNA
33 ng x cm/µL
