Luminex xPONENT 3.1 - Manual (Page 37)

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Touring the Software
• Timeout - Select Enabled to enable a timeout. Acquisition stops once the timeout is
reached. Type a value from 1 to 250 seconds.
• XY heater - Select Enabled to enable the XY heater. In the box, type the desired value
in degrees Celsius. The temperature range is 35 to 60°C in 0.5 increments.
WARNING: Acquiring data before the heater has reached the proper
temperature can compromise test results.
• DD gating - Use this to set the minimum and maximum DD gating values. Use values
within the range of 0 to 32767. In the first box, type the minimum value. In the second
box, type the maximum value. The default minimum and maximum values are 7500
and 13500 respectively.
• Reporter Gain - Select High PMT to increase the reporter gain level. Refer to assay
application instructions for more detailed information.
Analysis Settings. Use this section to set the analysis type, set the number of standards
and controls, select an external analysis program, and choose whether to analyze results
while acquiring samples.
• Analysis Type - Use this list to choose from the following analysis types:
• None - No analysis. Select if you have your own data post-processing program and
want to obtain only fluorescent intensity results. You cannot apply standards or
controls when you select None. You cannot analyze acquisitions with this setting.
• Qualitative - Qualitative analysis determines results as either positive or negative,
reactive or non-reactive. The software is flexible in defining custom result ranges,
such as negative, low positive, or high positive. Determinations are based on a
single standard. For qualitative analysis the Luminex software uses a specific
algorithm, shown below.
Where FI = Fluorescent Intensity and Ki = a “Quali” value entered in lot information to
determine the value or the qualitative assay standard.
The “Quali” value determines a cutoff or threshold. This, in conjunction with ranges
using the Lum Qual formula or an edited range specific for your assay, helps to
determine qualitative results for unknown samples.
Two predefined formulas using the algorithm are included in the system. You can use
them as is or edit their range values to meet your requirements. For information about
changing the analysis settings, see “Analysis Settings Dialog Box” on page 28 and
“Analysis Settings Dialog Box” on page 29.
• Quantitative - Determines the sample concentrations from standard curves using
regression methods Cubic Spline, Linear, Logistic 4P, Logistic 5P, Luminex
Logistic 4P, and Luminex Logistic 5P. Type the desired values for standards and
controls in the Number of Standards and Number of Controls boxes. Select either
Fit of All Standards or Mean of Replicates for the calculation of the curve fit.
NOTE: There are two forms of the 4P and 5P regression formulas. When
you change from one formula to another, xPONENT displays the
formula. The Luminex Logistic 4P regression is calculated as y =
a + b/(1 + (x/c) ^ d), while the widely used Logistic 4P regression
formula is calculated as y = a + ((b-a)/(1+(x/c) ^d)). The Luminex
Logistic 5P regression is calculated as y = a + (b/(1 + ((x/c) ^ d))