5 operation – Eppendorf BioPhotometer User Manual

Page 18

5 Operation

Measure sample

Results display

As an indication of the purity of the nucleic acid sample which
has been measured, the absorbance at 230, 280 and 320 nm
as well as the ratios A

260

280

and A

260

230

are displayed in

addition to the concentration result and the absorbance at a
wavelength of 260 nm. With pure samples, the absorbance at
320 nm should be approximately zero.

Turbid measuring solutions show increased absorbances for
all wavelengths. These can adulterate the results. In such
cases the inﬂuence on the result can be partially corrected by
switching on the "Corr. with A

320

" parameter. (Chapter 6.3

"Explanation of parameters")

Measure
next sample

To measure the next sample, press the

key again.

Sample dilution

The sample dilution in the measuring cuvette can be entered
using the

key before the measurement starts and is

included automatically in the result calculation (see
"Measuring diluted samples").

Conversion key

The most-recently measured concentration result can be
converted into molar concentrations and/or into nucleic acid
quantities (unit of mass or unit of mol):

Entering "TOTAL SAMPLE"

The value entered is converted using the concentration
measured. The result shown is the quantity of nucleic acid
present in the sample.

Entering "BASE PAIRS" or "MOL.MASS"

It is sufﬁcient to make an entry in only one of the two lines.
The molar concentration is calculated using the value
entered and the concentration measured.

Input ﬁelds can be skipped using the

key.

Sample

d s D N A

S A M P L E 0 0 1

0 . 6 9 4 A

2 3 0

1 . 4 0 8 A

2 6 0

1 . 9 7

2 6 0

2 8 0

0 . 7 1 5 A

2 8 0

2 . 0 3

2 6 0

2 3 0

0 . 0 0 2 A

3 2 0

µg/mL

Sample

Dilution

Conversion

C A L C. A M O U N T:
TOTA L S A M P L E –

–

µL

C A L C. M O L A R I T Y:
B A S E PA I R S

–

M O L . M A S S

–

– k D a

Enter

05_Bedienung_e.fm Seite 60 Dienstag, 21. Februar 2006 10:09 Uhr