PerkinElmer EnVision, Instrument Manual

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Functional description
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Measurements can also be made from below if the appropriate modules are
included.
In Ultra Sensitive Luminescence and HTS AlphaScreen the detector is a
very high sensitivity PMT.
Apertures
In Ultra Sensitive luminescence and HTS AlphaScreen measurement, an
aperture is used to guide light from the sample into the detector. This
reduces signal loss due to light spreading out from the sample. It also
minimizes crosstalk from adjacent samples.
There are different sizes of aperture: for 1536, 384 and 96-well plates
respectively. Apertures also differ depending on if they are for HTS
AlphaScreen or one of the luminescence modes. You can use an aperture
smaller than the sample well e.g. a 1536-well plate aperture for a 384-well
plate. This will minimize the crosstalk although there will be some signal
loss because the aperture size is not optimum.
The system checks that the selected aperture is in place and gives a warning
message if it is not. You can still continue despite this warning if you
choose to.
A shutter is available to protect the additional detector from dust when it is
not being used e.g. for several days or longer. This shutter must be used
instead of an aperture when standard AlphaScreen measurements are made
because the other apertures prevent the detector and plate cooler from
coming close enough to the plate to make successful standard AlphaScreen
measurements.
Test plate
A test plate is supplied with every instrument. This includes multilabel solid
samples covering all technologies and commonly used labels.
Measurement features
Your instrument has the following measurement features:
Fast dual TRF
Homogeneous TRF-assays can be measured extremely rapidly and with
high sensitivity.
Multiple window TRF
The multiple window TRF option opens up the possibility to record the
signal in separate windows within one flash cycle. The need to follow a
change in the emission profile of a lanthanide chelate is of practical