Section 18- Appendices
Alexa Fluor 594
73000
590
Alexa Fluor 647
239000
650
Alexa Fluor 660
132000
663
Cy3.5 150000
581
Cy5.5 250000
675
Nucleic Acids
For nucleic acid quantification, the Beer-Lambert equation is modified to use an extinction coefficient with units of ng-
cm/ml. Using this extinction coefficient gives a manipulated equation:
c = (A * e)/b
Where
c
is the nucleic acid concentration in ng/microliter,
A
is the absorbance in AU,
e
is the wavelength-dependent
extinction coefficient in
ng-cm/microliter
and
b
is the path length in cm.
The generally accepted extinction coefficients for nucleic acids are:
•
Double-stranded DNA: 50 ng-cm/ul
•
Single-stranded DNA: 33 ng-cm/ul
•
RNA: 40 ng-cm/ul
For the NanoDrop
®
ND-1000 Spectrophotometer, path lengths of 1.0 mm and 0.2 mm are used compared to a standard
spectrophotometer using a 10.0 mm path. Thus, the NanoDrop
®
ND-1000 Spectrophotometer is capable of measuring
samples that are 50 times more concentrated than can be measured in a standard spectrophotometer.
Note
: Absorbance data shown in archive files are represented as displayed on the software screen. For Nucleic Acid,
Protein A280 and Proteins and Labels modules, data are normalized to a 1.0 cm (10.0 mm) path. For MicroArray, UV-Vis,
Protein BCA, Protein Bradford, Protein Lowry and Cell Culture modules the data are normalized to a 0.1 cm (1.0 mm)
path. For high absorbance UV-Vis samples, data are normalized to a 0.1mm path.
Solvent Compatibility
The NanoDrop
®
ND-1000 Spectrophotometer is compatible with most solvents typically used in life science laboratories.
These include: methanol, ethanol, n-propanol, isopropanol, butanol, acetone, ether, chloroform, carbon tetrachloride,
DMSO, DMF, Acetonitrile, THF, toluene, hexane, benzene, sodium hydroxide, sodium hypochlorite (bleach), dilute HCl,
dilute HNO3, dilute acetic acid.
All forms of Hydrofluoric Acid (HF) are incompatible, as the fluoride ion will dissolve the quartz fiber optic cable.
Decontamination of Measurement & Optical Surfaces
If decontamination is necessary, a sanitizing solution, such as a 0.5% solution of sodium hypochlorite (1:10 dilution of
common commercial bleach solutions – freshly prepared), can be used to ensure that no biologically active material is
present on the measurement pedestals. The metal fiber optic fittings are made from 303 stainless steel and are resistant
to most common laboratory solvents (see “Solvent Compatibility” appendix).Note: Do not use a squirt bottle to apply the
diluted bleach.
Setting Up a Dymo 400 Label Writer Printer
To set DYMO default label to print with ND-1000:
1. Open Control Panel, then Printers and Faxes
2. Right click on Dymo printer then select Properties
3. Under General tab, choose ‘Printing Preferences’ then ‘Advanced’. Then set the following:
•
Paper Size:
30256
•
Halftoning:
Super Cell
•
Print Quality:
Barcodes and Graphics
4. Click ‘OK’ to close this window then click ‘Apply’
5. Next, click on the ‘Advanced’ tab. Ensure that ‘Enable advanced printing features’ box is checked.
6. Click on ‘Printing Defaults’ then ‘Advanced’ and set the following:
•
Paper Size:
30256
•
Halftoning:
Super Cell
18-2
