WPI APOLLO 4000, Инструкция по эксплуатации

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APOLLO 4000
NITRIC OXIDE DETECTION
WORLD PRECISION INSTRUMENTS C-1
USING THE APOLLO 4000 TO
DETECT NITRIC OXIDE
Initial Set-up
Attach the nitric oxide sensor to the required sensor input channel on the APOLLO
4000. From the main Setup menu of the software, select the correct poise voltage
“Nitric Oxide” and appropriate Range for the selected channel. The electrode must
now be calibrated.
Calibration of the NO Sensor
Accurate measurements of NO require an accurate calibration. Three calibration
methods are described in this section. The first and most convenient method is based
on a simple chemical reaction which generates known amounts of NO (from NO-
2
).
This method can only be used with the 2.0 mm sensor (ISO-NOP).
The second method is based on the decomposition of the S-nitrosothiol NO-donor,
SNAP using either Cu(I) as described in Method I or Cu(II) as outlined in Method II,
as a catalyst. The NO liberated from SNAP is used to calibrate the sensor.
The third method involves preparing aqueous solutions of NO standards from saturated
NO solutions.
The Calibration Kit
Perform the calibration using the NO calibration kit (WPI catalog #5435 ) which consists
of the following items:
Plastic stand with two holes; two glass vials; two silicon septums without holes;
two silicon septums with holes and radial slit; one short needle; one long needle.
The chemicals required for the calibration are not provided.
NOTE: The NO chamber (WPI # NOCHM ) can be used as an alternative to the use
of the calibration kit. Designed specifically for use with 2.0 mm electrodes, the
chamber can be adapted to other probes. Calibration temperatures from 4 - 40
°
C
can be controlled using an external circulating bath.