FlexStation 3 Benchtop Multi-Mode Microplate Reader User Guide
166
0112-0127 B
Stokes Shift
The Stokes shift is the difference between the wavelengths of the
excitation and emission maxima, or peaks.
Time-Resolved Fluorescence
Time-resolved fluorescence (TRF) is a measurement technique that
depends on three characteristics that lead to better discrimination
between the specific signal, proportional to the amount of label, and the
unspecific fluorescence resulting from background and compound
interference:
•
Pulsed excitation light sources
•
Time-gated electronics faster than the fluorescence lifetime
•
Labels with prolonged fluorescence lifetime
The time-gating electronics introduce a delay between the cut off of each
light pulse and the start of signal accumulation. During the delay, the
unspecific fluorescence (caused by test compounds, assay reagents, and
the microplate) vanishes while only a small portion of the specific
fluorescence from the label is sacrificed. Enough of the specific signal
remains during the decay period with the added benefit of reduced
background.
Trituration
Trituration is mixing of the contents of the wells in either or both the
compound source and assay plates. Trituration is accomplished by fluid
being alternately aspirated from and dispensed back into a well using the
pipettor head.
FlexStation_manual.book Page 166 Tuesday, June 25, 2013 10:22 AM
