Eppendorf BioPhotometer - Manual (Page 44)

86
12 Calculation
12.1 Nucleic acids (dsDNA, ssDNA, RNA, oligo)
Calculation via factor
C = A 260 x F
C = Calculated concentration
A 260 = Absorbance measured at 260 nm
F = Factor (method-specific programming using the key)
The nucleic acid methods have the following special feature: The programmed factor is always based on the
unit of concentration "
µ g/mL". If the unit of concentration " µ g/ µ L" is selected, the factor is converted internally:
F’ = F / 1000
F’ = Converted factor; used for the calculation of the concentration.
Sample dilution
C
Dil, corr
= C x (V
P
+ V
Dil
) / V
P
C
Dil, corr
= Result converted using dilution factor
V
P
= Volume of the sample in the measuring solution (entered using the key)
V
Dil
= Volume of the diluent in the measuring solution (entered using the key)
Optical path length of the cuvette
Application: Using cuvettes with an optical path length of 1 mm, 2 mm or 5 mm.
The optical path length of the cuvette can be programmed for each method using the key.
A
cuv, corr
= A x 2 (with an optical path length of 5 mm)
A
cuv, corr
= A x 5 (with an optical path length of 2 mm)
A
cuv, corr
= A x 10 (with an optical path length of 1 mm)
A
cuv, corr
= Absorbance converted in accordance with an optical path length of 10 mm
Correction A 320
Application: Partial correction of incorrect absorbance caused by turbidity in the measuring solution.
The calculation procedure with or without correction A 320 can be programmed for each method using the
key.
A
x, corr
= A
x
- A 320
A
x, corr
= Absorbance at wavelength of 230, 260 and 280 nm, corrected mathematically
A
x
= Absorbance measured at wavelength of 230, 260 and 280 nm
A 320 = Absorbance measured at wavelength of 320 nm
The corrected absorbance is used for further calculation of results.
Conversion key: Calculating the quantity
Application: Calculating the quantity of nucleic acid in the total sample volume.
M = C x V
P, total
M = Calculated overall quantity of nucleic acid in sample vessel
C = Calculated concentration
V
P, total
= Volume of the sample in the sample vessel (entered using the key)
Parameter
Dilution
Dilution
Parameter
Parameter
Conversion
12 Calculation
12_Auswertg_e.fm Seite 86 Montag, 20. Februar 2006 11:34 Uhr