Table of Contents
Advertisement
Protein A280 settings
Setting
Available Options
Sample
1 Abs = 1 mg/mL
a
type
BSA
Thermo Scientific
The Protein A280 application provides a variety of sample type options for purified
protein analysis.
Each sample type applies a unique extinction coefficient to the protein calculations. If
the extinction coefficient of the sample is known, choose the
(mass) option and enter the value. Otherwise, calculate the extinction coefficient or
choose the option that best matches the sample solution. If you only need a rough
estimate of protein concentration and the sample extinction coefficient is unknown,
select the 1 Abs=1 mg/mL sample type option.
Tip Ideally, the extinction coefficient should be determined empirically using a
solution of the study protein at a known concentration using the same buffer.
Mass Ext.
Coefficient
(L/gm-cm)
General reference
6.7
Description
Recommended when extinction coefficient is
unknown and rough estimate of protein
concentration is acceptable for a solution with
no other interfering substances. Assumes
0.1% (1 mg/mL) protein solution produces
1.0A at 280 nm (where pathlength is 10 mm),
i.e.,
1% = 10.
Calculates BSA (Bovine Serum Albumin)
protein concentration using mass extinction
coefficient (
) of 6.7 L/gm-cm at 280 nm for
1% (i.e., 10 mg/mL) BSA solution. Assuming
MW is 66,400 daltons (Da), molar extinction
coefficient at 280 nm for BSA is approximately
-1
-1
43,824 M
cm
.
NanoDrop One User Guide
5
Protein Applications
Measure Protein A280
+ MW (molar) or
1%
67
Advertisement
Table of Contents
