Eppendorf BioPhotometer - Manual (Page 21)

63
5 Operation
5.4 Measuring proteins with reagent (Bradford, BCA, Lowry)
Call up method
If a valid calibration (which is then stored by the device) has already
been performed, the date and time of the stored calibration appear.
In this case, the method can be recalibrated after blank
measurement or the sample measurements may begin directly and
can then be calculated using the previously stored calibration.
Micro methods
The Bradford, Lowry and BCA methods have a special feature:
Two different concentration ranges may be programmed for each
of these methods. It is possible to toggle between the two methods
(e.g. "BCA" and "BCA micro") by pressing the method key
repeatedly.
Calculation
For the Bradford, Lowry and BCA methods, the device contains a
factory-set calibration procedure via multiple-point calibration and
calculation of a calibration curve via non-linear regression. Other
calculation methods may be programmed using the
key
(see Section 6 "Programming"):
– Factor (calculation of concentration values via factor).
– Absorbance (the measured values appear as absorbance
values with no further calculation).
The following parameters may be changed for the factory-set
calculation procedure via standard (see "Programming").
– Number of standards (1 to 10).
– Number of multiple measurements per standard (1 to 3).
– Calculation procedure for multiple-point calibration (linear or
non-linear calibration).
– Nominal concentrations of the standards.
The number of decimal places of the preprogrammed factor or the
preprogrammed nominal concentration of the standard determines
the number of decimal places in the result.
In the case of calculation via factor, please ensure that the factor is
adapted in line with the unit of concentration selected.
1
Bradford
B R A D F O R D
C A L I B R AT I O N R A N G E
X X X – X X X
µg/mL
Blank Standard or
Parameter
05_Bedienung_e.fm Seite 63 Dienstag, 21. Februar 2006 10:09 Uhr