WPI APOLLO 4000, Инструкция по эксплуатации

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APOLLO 4000
HYDROGEN PEROXIDE DETECTION
World Precision instruments e-4
Interference
Temperature
the background current of the sensor will usually increase with increasing
temperature of the experiment. Although, the sensitivity of the sensor does not
change significantly within the range 0-37°c. it is therefore recommended that
any calibration should be performed at the same temperature as the experiment.
pH
Between pH 3-0, changing the pH of the solution does not affect the sensitivity
of the HPo sensor. However if the pH is below 3.0, the noise of the sensor
will increase. At pH 0.0 and higher, the response of the sensor will diminish
significantly.
Maintenance of HPO Sensors
When the iso-HPo- sensor is not being used (and for short-term storage)
it should be connected to the APollo 4000 with power on and with the tip
suspended in distilled water. tthis will keep the sensor polarized and ready for
immediate use.
Clean the Membrane
the membrane sleeve itself requires very little maintenance. the primary concern
is to avoid to damage the membrane and to keep it as clean as possible. After
each use, the membrane should be cleaned by suspending the tip in distilled
water for 0-30 minutes to dissolve salts and remove particles ,which may
have accumulated on the membrane. if the probe was used in a protein rich
solution the tip should first be soaked in a protease solution for several minutes
to remove protein build-up, and then in distilled water. enzymatic detergent
(e.g., enzol, WPi#
7363 ) can also be used. the membrane sleeves can also be
sterilized chemically using an appropriate disinfectant (e.g., cidex, WPi# 7364 ).
Accumulated organic matter can be removed by briefly immersing the tip in an
acid or base solution (at times both may be necessary) for 0 seconds. A good
indication of a dirty membrane sleeve is a sluggish response or an unusually low
sensitivity. if these problems are not rectified by the above cleaning procedures
then the membrane sleeve should be replaced. the probe cannot be used in
organic solvents.