PerkinElmer QuantaSmart 1694267, Справочное руководство

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CHAPTER 5
76 PerkinElmer Life and Analytical Sciences
Quench Standards Assay
A Quench Standards set is composed of a series of vials, each containing the
same amount of nuclide with varying amounts of quenching agent. Using the data
from the quench standards, a quench curve is generated to determine the
counting efficiency for a sample and calculate DPM (Disintegrations Per Minute),
where DPM=CPM/Efficiency. The system stores the spectrum of each standard in
the quench standards set. The quench standards set needs to be counted one
time only, as the quench data is available for use with any protocol.
To accurately assess the level of quench within a sample, the nature and
composition of the quench standards should reflect the matrix and environment of
the samples you would like to count.
Performing a Quench Standards Assay
The following tasks are required when performing a Quench Standards Assay.
„
Calibrate the instrument, if necessary.
„
Create a new assay, choosing Quench Standards as the assay type and
define the new assay parameters, OR Open an existing Quench Standards
Assay and edit or review if necessary. Save the assay in the Assays folder of
the Packard\TriCarb directory.
„
Associate (link) the assay parameters with a protocol and attach the
corresponding protocol flag to the first cassette to be counted.
„
Load the cassette(s) with vials and load the instrument with cassettes.
„
Start the instrument.
Note:When using the Low Level count mode, you must not use
quench standards which have been purged free of oxygen with an
inert gas. The oxygen quenching in unpurged standards facilitates
discrimination between background and true beta events.
Unpurged quench standards are available from PerkinElmer Life
and Analytical Sciences.