WPI ISO-HPO-2, Руководство пользователя

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ISO-HPO-2
World Precision Instruments 3
Gas permeable membrane –The membrane covers the end of the stainless sleeve
to separate it from the external environment.
Stainless steel sleeve (WPI# 600012, pkg. of 4)–The sleeve houses the sensitive
electrode pair. The sleeve is flanged to properly connect with the locking cap. It must
contain fresh filling solution (WPI# 100042 ).
Working/Counter electrode –This is an internal H
2
O
2
-sensing pair of working and
counter (reference) electrodes.
Locking cap– This cap attaches the sleeve to the probe handle.
When the sensor is assembled (with locking cap and sleeve in place) the internal
electrode should press gently against the polymeric membrane, which will be slightly
stretched . This ensures that the electrolyte diffusion is as thin as possible, minimizing
sensor response time.
NOTE : Once a membrane is stretched it is permanently deformed and cannot be
reused if the sleeve is removed from the electrode.
Additional membrane sleeves are available in packages of 4 (WPI #
600012 ). The
ISO-HPO-2 start-up kit (WPI # 600011 ) also includes replacement membrane sleeves,
along with all the accessories to fill them properly with filling solution (electrolyte).
OPERATING INSTRUCTIONS
Polarizing the Sensor
1. Measure an appropriate volume (for example, 10mL) of 0.1M PBS buffer solution
into a glass vial. Place the vial on a magnetic stirring plate and put a small stir bar
into the vial. Set the stir rate at a medium speed.
2. Remove the sensor from the filling solution in which the tip has been immersed
during storage. See the Probe Unpacking Instructions included with your sensor.
NOTE : Some sensors are shipped or stored dry. For these sensors, you will need
to install the membrane sleeve (included). See “Replacing the Membrane Sleeve”
on page 7.
3 Immerse the ISO-HPO-2 sensor tip in PBS buffer solution. The sensor tip should
be immersed about 0.3-0.5mm into the solution, and should not be touched by
the stir bar.
4. Connect the ISO-HPO-2 sensor to the input on the free radical analyzer.
5. Turn on the free radical analyzer ( TBR4100/1025) .
6. Select the poise voltage for hydrogen peroxide on the free radical analyzer. On
the TBR4100/1025 , set the Probe Select switch to HPO (+450mV).
NOTE : It is important that the poise be set correctly to avoid erroneous results.
7. Set the current range to 10nA