ABI Prism® 7900HT Sequence Detection System ... - OpenWetWare

Determining
T m Values
The following table describes the elements of the Dissociation Plot: (continued)
Component Description
Plot drop-down list Chooses the data displayed within the plot based on the derivative
calculation. The list offers the following selections:
♦ Raw – When selected, this option plots the normalized reporter
fluorescence data (Rn ) on a graph of fluorescence vs. temperature
(see below left).
♦ Derivative – When selected, this option plots derivative data (Rn ´)
on a graph of the derivative vs. temperature (see below right). The
derivative data is the negative of the rate of change in fluorescence
as a function of temperature.
The following figures show the plots accessible from the Plot drop-down list.
Detector
drop-down list
Raw Plot Derivative Plot
Chooses the data displayed within the plot based on detector name.
To determine the T m value of a melting curve within the Dissociation Plot:
Step Action
1 Move the mouse pointer over the green Tm line located on the Y-axis line of the plot.
The mouse pointer becomes a hand.
2 Click and drag the Tm line to the maximum point of the derivative plot of interest.
The SDS software displays the T m for the curve below the T m line.
T m display and slider
Note The apex of the curvature of represents the maximum rate of change in
normalized fluorescence.
Real-Time Analysis 6-23