PerkinElmer QuantaSmart 1694267, Reference Manual

Page: 85 / 218

ASSAYS
PerkinElmer Life and Analytical Sciences 75
Alpha Beta Standards Assay
An Alpha Beta Standards Assay allows you to count pure beta and pure alpha
standard sources. By counting the beta and alpha standards, you can establish
the optimal Pulse Decay Discriminator value, where misclassification of the beta
and alpha events is at a minimum. Establishing this value allows the instrument to
discriminate between alpha and beta emitting nuclides in your samples in Alpha
Beta Assays.
Performing an Alpha Beta Standards Assay
The following tasks are required to run the Alpha Beta Standards Assay. Two
standards are required, a pure beta emitter and a pure alpha emitter.
„
Choose the Alpha Beta Standards selection from the Libraries menu.
„
Click the Add button and enter the name for a new Alpha Beta Standard Set.
„
Choose Automatic for the Discriminator Type if your pure alpha and pure
beta standards have an activity of at least 50,000 CPM each. If the activity in
either standard is less than 50,000 CPM, choose Manual as the Discriminator
Type by clicking on it.
„
The remaining fields are for information only. They are either default values
or values computed by the instrument.
„
Choose File-New and select Alpha Beta Standards as the assay choice from
the drop down menu.
„
Click the Name button on the Count Conditions Tab to choose from the list of
Alpha Beta Standard names in the Alpha Beta Standards Library. Define the
other available assay parameters as desired.
Note:High Sensitivity or Low Level Count mode are not available
when counting Alpha Beta Standards, but will be available when
counting samples in an Alpha Beta assay
„
When the assay definition is complete, name and save the assay.
„
Associate (link) the assay parameters with an available protocol flag in the
protocol tree. Place the numbered protocol clip on a cassette.
„
Place the pure beta emitter standard in cassette position 1 and the pure
alpha emitter standard in cassette position 2.
„
Click the green start button at the top of the main window.
„
After counting is complete, the misclassification (or spillover) curve and the
optimum discriminator value will be stored in the Alpha Beta Standards
Library.