Section 9- Proteins & Labels
Sample
Type
Detection
Limit
Approx.
Upper
Limit
Typical Reproducibility
(minimum 5 replicates)
(SD= mg/ml; CV= %)
Purified BSA
0.10 mg/ml
20 mg/ml
sample range 0.10-10 mg/ml:
±
0.10 mg/ml
sample range >10mg/ml:
±
2%
Cy3
0.2uM
100uM
sample range 0.20-4.0 pmol/ul:
±
0.20 pmol/ul
sample range >4.0 pmol/ul:
±
2%
Unique Screen Features
Max Absorbance:
used to rescale the upper limit of the vertical axis.
Sample Type:
The same six sample types (options) listed under Protein A280 (Section 8) are available for purified
Proteins & Labels analysis and concentration measurement. All of the options can be viewed by clicking the mouse while
it is positioned within the sample type box. The sample type (color-keyed) can be selected by clicking on the preferred
option or by scrolling through the selections using the up or down arrow keys located to the left of the sample type box.
See Protein A280 (Section 8) for a detailed description of each sample type.
λ
3:
user-selected wavelength
Norm Abs @
λ
3:
10mm equivalent normalized absorbance at the respective wavelength.
Dye 1 (or 2):
user-selected dye
Norm Abs @
λ
1:
normalized 10 mm equivalent absorbance of selected Dye
uM:
concentration based upon selected Dye’s extinction coefficient. See the “Concentration Calculation (Beer’s Law)”
in the Appendices for more details on this calculation.
Abs ratio
λ
1/
λ
3:
ratio of the absorbance of Dye 1 to the absorbance at the user-selected wavelength (
λ
3).
mg/ml:
concentration of proteins in the sample calculated using the absorbance at 280 nm minus the absorbance at 340
nm (i.e. normalized at 340 nm). See the “Concentration Calculation (Beer’s Law)” Appendices for more details on this
calculation.
Baseline Type
This application module has two user-selectable “Baseline Type” options. The default setting is set to normalize the
display spectrum at 750nm. Alternatively, the 400-750 Slope Baseline Type will normalize the display at 750 nm and
accommodate any linear baseline offset across the 400 to 750 nm range.
9-2
