PerkinElmer EnVision, Instrument Manual

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Functional description
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Crosstalk correction for AlphaScreen or HTS AlphaScreen
A crosstalk correction wizard allows the setup and measurement of the
contribution to the signal from a sample well due to the glow and afterglow
of adjacent samples and the effect of bleaching. The software then corrects
for these effects in the calculation of the final results.
Reading from above and below
Fluorescence intensity and time-resolved fluorescence readings can be taken
from above or below. Reading from above is the most efficient way when
no lid is used because no plastic surface has to be penetrated. For adherent
cells and lidded plates, reading from below provides superior efficiency. It
is a true epimode, in the sense that both excitation and emission are from
below.
Switching between reading from above to reading from below and vice
versa is purely a software issue and for the same run both above and below
can be used.
Shaking
The shaker accommodates the wide range of plates and applications for
which EnVision is suited. Three modes are available; linear, orbital and
double orbital. The duration, speed and amplitude of shaking can all be
defined by the user.
Scanning
Cell applications, require several reading points in one well. Due to the
heterogeneous spread of cells in a well it is important to scan the complete
area of the cell culture. This can be done with EnVision by specifying the
shape of the scan area and the number of points to be scanned. The scanning
function is also suitable for the reading of small membranes, chips and
slides.
Kinetics
In both slow and fast kinetic assays, EnVision allows faithful reproduction
of physical conditions. Delays and repeats can be specified by plates or
wells. Specific operation sequences can be defined by well or by well group.
Dispensing
A dispenser unit can be installed in EnVision. This enables dispensing to
microplates and is needed for applications requiring real time reading after
activation, such as cellular ion-channel and flash luminescence assays. Real
time measurements with dispensing can be done with the “Real time” tip in
a tip mount. The well is directly below the measuring head when dispensing
takes place so there is no delay between dispensing and measurement.