Sipper - biochrom ultrospec 7000 User Manual

17 . Sipper

The Sipper and Flowcell accessories for the Ultrospec range of instruments are
designed as an aid to speed up sample handling. The system comprises a peristaltic
pump head that is controlled by the software to sip a known, calibrated volume
of sample and move this into a Flowcell which is in the sample position of the
spectrophotometer.
The Sipper can be set up and used within all applications and Sipper parameter are
stored as part of an application method.
17 .1. Setting Sipper defaults
It is simple to customize the default parameters of the Sipper for a particular
installation by setting all of the default values. Every application will then load
these defaults each time the Sipper page is opened however they can be changed
within the application. These default values are set within the instrument under the
Settings, Accessories, Sipper Icons and are stored even when the instrument is
switched off.
Sip Volume
• Amount of sample to be sipped up. Range of values = 0.3 ml to 50 ml.
Note: working with volumes less than 1 ml will require careful setting of the air gap to
minimize cross contamination between samples.
Air-gap
• Gap between successive samples which is set by pumping air after the tube has
been removed from the sample liquid – set in cm of tubing. Range of values = 0
to 200 cm.
The Sipper has the ability to program an air gap between samples to help minimize
cross contamination and to allow users flexibility to work with different volumes and
lengths of Sipper inlet tubing. When the start button is pressed the Sipper pumps up
the volume of sample that is set within the method and the user is then prompted to
remove the tubing from the sample. After a short delay the pump starts again and
the sample is moved along the tubing and air is sucked into the end of the tubing.
The default air gap set in the software is 40 cm which has been set to work with a
65 cm length of tubing on the Flowcell inlet. If a different length of tubing is used then
a different default air gap will need to be set. To calculate this default air gap:
• Measure the length of tubing connected to the Flowcell tubing inlet and take
20 cm from this value.
• From the home page go into a single wavelength method and enter through until
you get to the Sipper parameter page. Set the volume to 1 ml and the air gap to
the value measured above. Set the settle time to 1 second and Auto read to off.
• Sip a sample of water, remove the tube from the sample when prompted and
note the position of the end of the sample slug – you need this to be stopping
above the inlet position to the Flowcell. For a 1 ml sample volume you should
have this stopping 15-25 cm above the Flowcell inlet. To move the position of the
sample press the menu icon, parameters icon, step through the method until you
reach the Sipper parameters and adjust the air gap value. Increasing the value
will move the end of the sample closer to the Flowcell inlet, lowering the value
will move it further away.
• Once the value has been determined exit the Single wavelength application, go to
Settings, accessories, Sipper and enter this value in the default air gap box.
Settle time
• Amount of time before the system is ready to measure after the sample has
entered the Flowcell. Value entered in seconds. Range of values = 1 to 30 seconds
29004782UM AA 10/2011
5061-046 Rev1
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