Photon Systems Instruments AquaPen-C AP 110-C, Instruction Manual

Page: 26 / 52

Page | 26
5.2 O
PTICAL DENSITY MEASUREMENT
(A
QUA
P
EN
-C
ONLY
)
5.2.1 C
ALIBRATION
Calibration of the AquaPen is required before measuring OD. It can be done with either plain water or ideally, culture medium placed in
a cuvette and the AquaPen. Calibration assures accurate OD measurements and it is recommended before every set of samples.
It is highly recommended to calibrate AquaPen for OD measurements every time the instrument is switched ON.
Steps for calibration of the AquaPen for OD measurements:
•
Use the standard 4 ml cuvette.
•
Clean the cuvette with distilled water and paper tissue.
•
As a calibration standard use cultivation medium (BBM, BG11 etc.) or distilled water.
•
Put cuvette with medium (optimal volume 3 ml) into the AquaPen cuvette holder.
•
Turn ON the device – hold SET button for 1 sec.
•
select Measurement > OD > Calibration.
•
Press SET button to start the calibration.
•
To check the validity of the calibration, select Measurement > OD > OD680nm (or OD720nm) with the blank cuvette in the AquaPen.
•
Press SET to do the measurement.
•
The display should show value of 0.000.
•
If the OD value is different than 0.000 repeat OD calibration again.
•
Remember that the calibration is specific to a particular cuvette. New calibration should be performed for a new cuvette.
•
Calibration is automatically stored in the device memory and is saved until the device is turn OFF.
Please remember or mark the orientation of the cuvette when placed in the device. For repeated measurements
it is recommended to position the cuvette always in the same orientation in the AP cuvette holder.
5.2.2 M
EASUREMENT
•
Fill the cuvette with a sample of algae or cyanobacteria and close the cuvette with the stopper. Minimal volume of sample is 2 ml.
•
Place the cuvette with sample inside the AquaPen cuvette holder.
•
Close the cover.
•
Turn the device on by pressing SET key for 1 sec
•
Select from the menu Measurement > OD680nm or OD720nm.
•
Press SET to start the measurement.
•
Value of the measured parameter will appear on the display. All measured data are stored in the AquaPen memory and can be
downloaded to a PC via USB connection or Bluetooth connection using FluorPen software (page 44).