Molecular Devices FLIPR Tetra, Руководство пользователя

Страница: 167 / 302

FLIPR
®
Tetra High Throughput Cellular Screening System User Guide
0112-0109 H 167
Basal fluorescence too high:
• Decrease the Excitation Intensity .
• Decrease the Exposure Time .
• Decrease the Camera Gain (EMCCD camera).
• Decrease the Gate Open (ICCD camera).
Adjusting the Pipettor Height
To ensure prompt compound delivery, the pipettor height can be
adjusted. It is based on pipettor mechanics and the physics of liquid.
for Fluorescence an air gap, called the Hold Volume , is drawn into the
tips after fluid aspiration from the source plate. This air gap ensures
fluid doesn’t leak out during pipettor movement. The hold volume will
be the first item to leave the pipette tip during dispense and enters the
target well as a bubble. These bubbles may cause random light
reflections and spurious signals. To avoid bubbles, fluid dispensing
should occur with tips just above, but touching the initial well fluid
level. This will leave the tips touching the meniscus after the addition
has been completed to ensure complete sample dispensing.
If pipette tips are in the air at the end of fluid delivery, a drop can form
on the tip end due to surface tension resulting in reproducibility
problems. Therefore, the pipettor height should be set just above, but
touching the starting fluid volume in the wells.
The fluid surface in a 384- or 1536-well plate is a deeply curved
meniscus. Therefore, we recommend setting the pipettor height
somewhere below the starting fluid volume for the 384- or
1536-pipettor.
Note: For Luminescence suspension assays, no Hold Volume is
recommended along with low and fast addition.