Thermo NanoDrop One User Manual

Measure OD600
Thermo Scientific NanoDrop One User Guide 137
Calculations for OD600 Measurements
Similar to the nucleic acid applications, the OD600
application uses a modification of the Beer-Lambert
equation to calculate sample concentration where the
extinction coefficient and pathlength are combined and
referred to as a “factor.”
The OD600 application offers a user-specified factor, to
be used in conjunction with Beer’s Law to calculate
sample concentration. If the factor is known, enter the
factor. Otherwise, use 1x10
8
, which is the generally
accepted factor for most bacterial cell suspensions such
as E. coli.
Measured Values
A600 absorbance
Note: For micro-volume absorbance measurements and measurements
taken with nonstandard (other than 10 mm) cuvettes, the spectra are
normalized to a 10 mm pathlength equivalent.
• Cell culture absorbance values are measured at 600 nm using the
normalized spectrum. If no Absorbance Correction is specified, this is
the reported A600 value and the value used to calculate cell
concentration.
•If an Absorbance Correction is specified, the normalized and
(absorbance) corrected absorbance value at 600 nm is reported and
used to calculate cell concentration.
A(
) absorbance
• Normalized and (absorbance) corrected (if used) absorbance value at
any specified Additional Monitored Wavelength (
) is also reported.
Calculated cell concentrations are based on the
absorbance value at 600 nm, the entered factor and the
sample pathlength. A single-point absorbance correction
may be applied.
Sample Pathlength
• For micro-volume measurements, the software selects the optimal
pathlength (between 1.0 mm and 0.03 mm) based on sample
absorbance at the analysis wavelength.
• For cuvette measurements, pathlength is determined by the cuvette
Pathlength setting in the software (see General Settings).
• Displayed spectra and absorbance values are normalized to a 10 mm
pathlength equivalent.
•
Reported Values
Cell concentration. Reported in cells/mL. Calculations are based on
Beer-Lambert equation using corrected A600 absorbance value.

Thermo NanoDrop One Specifications

General

Wavelength Range	190-850 nm
Pathlength	1 mm and 0.2 mm (Auto-ranging)
Detection Limit	2 ng/µL (dsDNA)
Light Source	Xenon flash lamp
Maximum Concentration	15, 000 ng/µL (dsDNA)
Detector	2048-element linear silicon CCD array
Measurement Time	< 5 seconds
Weight	2.0 kg (4.4 lbs)
Nucleic Acid Quantitation	Yes
Protein Quantitation	Yes
Display	7-inch capacitive touch screen
Sample Volume	1-2 μL
Absorbance Precision	±0.002 A
Operating Voltage	100 to 240 V AC
Dimensions (W x D x H)	20 cm x 25 cm x 15 cm (8 in. x 10 in. x 6 in.)
Software	Thermo Scientific™ software
Connectivity	USB, Ethernet, Wi-Fi
Operating Temperature	15 - 35°C
Dimensions	20 cm x 25 cm x 15 cm (8 in. x 10 in. x 6 in.)
Absorbance Range	0 - 550 A (10 mm equivalent)