• Reduce cost and length by 50% or more on whole-genome sequencing projects
  View Webinar | PowerPoint Presentation
• ELISA Curve-Fitting Analysis with ReaderFit.com
  View Webinar | PowerPoint Presentation
• How can Optical Mapping accelerate my research?
  View Webinar | PowerPoint Presentation
• MasterPlex ReaderFit 101
  View Webinar | PowerPoint Presentation
• How to create the report you want out of MasterPlex?
  View Webinar | PowerPoint Presentation
• MasterPlex: One Quantitative Analysis Software Solution for Multiple Instruments
  View Webinar | PowerPoint Presentation
• Getting the Most Out of Your Multiplex Data
  View Webinar | PowerPoint Presentation

• 10 Tips for MasterPlex QT v4.0 Power Users on August 20th at 11AM – 12PM PDT – Reserve your seat!
• Microplate Reader/Elisa Data Analysis made easy with MasterPlex ReaderFit on September 10 at 11:00 AM – 12:00 PM PDT – Reserve your seat!

If you cannot make the time for the MasterPlex ReaderFit webinar, you can view a previously recorded video of it and obtain the PowerPoint presentation slides.

A recording of the MasterPlex QT webinar will be available online after August 20th, 2009.

1. Stand Alone – This is the most commonly used licensing scheme where each purchased license is installed on a single computer to run and activate the MasterPlex software. This is a perpetual license that does not expire. This is the most convenient scheme to manage and install. Stand Alone license installation instructions.
   

   MasterPlex Stand Alone Licensing Scheme

2. Network – This is a shared licensing scheme that involves the MasterPlex Network License Manager. For each x number of purchased licenses, there will be x number of allowed concurrent or simultaneous users using the MasterPlex software on the entire network. This means that the MasterPlex software can be installed on all the client computers that is on the same network as the MasterPlex Network License Manager. This scheme is usually more involved as far as the setup goes and could require your IT group to make sure the network security setup will allow such a configuration. Network license installation instructions.
   

   MasterPlex Network Licensing Scheme

3. Term – Term licensing is similar to Stand Alone licensing except that it expires after a certain duration. Term Licensing durations include the 3, 4, 5, 6, 7, 8, 12, or 24 month options. The software license expires at the end of the purchased term and also includes all major upgrades released during the term. Term license installation instructions.
   

   MasterPlex Term Licensing Scheme

With the exception of the Term Licensing, the type of license is not fixed to a sale: Rather it is decided when the time comes for the customer to fill out the online product registration form.

F(x) = A + (D/(1+(X/C)^B)^E)

• A is the MFI/RLU value for the minimum asymptote
• B is the Hill slope
• C is the concentration at the inflection point
• D is the MFI/RLU value for the maximum asymptote
• E is the asymmetry factor

The 5-PL model equation has the extra E parameter which the 4-PL model lacks and when E = 1 the 5-PL equation is identical to the 4-PL equation.

Anatomy of the 5 Parameter Logistic Model (5-PL)

Parameters A (minimum asymptote) and D (maximum asymptote) are the limits of where you can interpolate or extrapolate your data.  Any MFI/RLU values > D and MFI/RLU values < A simply cannot be calculated because they are out of the function range.

Limits of the 5-PL Standard Curve

What are the differences between extrapolation and interpolation?

Extrapolation occurs when you are inferring or estimating concentrations for points that are within calculable limits (A < x < D) but are outside of the range of our standard curve.  This occurs when the calculated Concentration < Minimum Standard Concentration or when the calculated Concentration > Maximum Standard Concentration.  For typical bioassay standard curves, extrapolating can be very dangerous and quite often be misleading.  The reason being that minute changes in MFI values on the flat parts of the standard curve can lead to huge changes in concentration or dose.

The Dangers of Extrapolation

Interpolation occurs when your MFI/RLU values are within standard range or Minimum Standard Concentration < x < Maximum Standard Concentration.  Ideally, this is the range where you would want all your unknown points to lie.

Extrapolation vs. Interpolation

The 5 Parameter Logistic model equation, by itself, is not equipped to give accurate and precise curve-fitting of bioassay data due to a phenomenon known as heteroscedasticity; the nonconstant variability that arises in almost all fields where chemical and bioassays are no exceptions.  In bioassays, measurement errors increase as concentrations get higher and therefore the variability of a measurement is not constant.

How does this affect curve-fitting? During curve-fitting, all standard samples are given equal freedom to influence the curve.  The only problem is that those points with higher errors (variance) are given the same freedom as those that are more accurate (points at the lower end of the curve).

How can we deal with this issue? One way to counterbalance nonconstant variability is to make them constant again.  To accomplish this, weights are assigned to each standard sample data point.  These weights are designed to approximate the way measurement errors are distributed.  By applying weighting, points on the lower part of the curve are given more influence on the curve again.

MasterPlex quantitative analysis software uses 4 different algorithms of assigning weights:

1. 1/Y^2 – Minimizes residuals (errors) based on relative MFI/RLU values.
2. 1/Y – This algorithm is useful if you know the errors follow a Poisson distribution.
3. 1/X - This choice is rarely used because it minimizes residuals based on their concentration values.  Gives more weight to the right part of the graph.
4. 1/X^2 – Similar to the above.

How can EC50/IC50 be calculated from the 5PL model equation? The formula for calculating the EC50/IC50 from the 5PL is as follows:

x = C((2^(1/E) – 1)^(1/B))

MiraiBio offers 2 powerful curve-fitting quantitative analysis solutions that utilizes our time-tested 5-PL nonlinear regression model as well as many others:

1. ReaderFit.com – This is the free online lite-version of MasterPlex ReaderFit with the same core curve-fitting algorithms.
2. MasterPlex ReaderFit for Elisa or Dose Response Analysis – MasterPlex ReaderFit is our Curve-Fitting Data Analysis Software Package Optimized for ELISA or Dose Response Analyses (e.g. EC50/IC50 or even IC90 calculations).  Download our 14-day free trial today!
3. MasterPlex QT for the Luminex xMAP 100/200 or Bio-Plex Platforms – The World’s First Multiplex Curve-Fitting Software for the Luminex 100 and Luminex 200 xMAP Platforms.  Download our 14-day free trial today!

You may also be interested in reading our blog post on:

• Dummies Guide to Curve-Fitting for Quantitative Analysis
• 4PL nonlinear regression model
• Tips for ELISA analysis
• The importance of weighting with the 4PL and 5PL
• Dose response analysis and EC₅₀/IC₅₀ determination

In addition to the online community members, MiraiBio’s own employees will be browsing around as well joining in on all the conversations.  So whether you were just curious about something or need help troubleshooting, feel free to drop by and start a converation!

Achieving a good standard curve fit is important for calculating unknown analyte concentrations (e.g. cytokine or chemokine) using xMAP assays. A good curve fit gives confidence in the final result. However for many the task can be daunting because there are so many variables:

1. Do I treat replicates at individual points or use the average value?

2. What if a replicate fails?

3. Do I use 4PL, 5PL or some other model equation?

4. When do I use a weighting algorithm and which on should I use?

5. How do I know I have achieved the best curve fit?

MasterPlex QT has always offered advanced features for customers who like to manipulate standard curve fitting parameters manually. The latest version of MasterPlex makes it even easier to quickly ascertain the quality of your fit and tweak it on the fly by selecting different model equations, weighting algorithms or throwing out saturated and/or failed standard replicates. The new interface puts everything you need to optimize your curve fit in to one tab so you can quickly make changes and compare results instantly.
The new Best Fit feature takes curve fitting to the next level. Of course you still have the option to tweak your curve fit to heart’s content but who has the time!

Test drive the new Best Fit feature now by downloading the fully-functional trial demo of MasterPlex QT v4.0!

We are now happy to introduce the new Term Licensing options for our MasterPlex QT and GT Luminex data analysis software.  Term Licensing durations include the 3, 4, 5, 6, 7, 8, 12, or 24 month options.  The software license expires at the end of the purchased term and also includes all major upgrades released during the term.

For those that do not need to run analyses 24/7, this may be the cost-efficient choice for you.  To find out more details, please visit the MasterPlex QT product page or the MasterPlex GT product page at the MiraiBio Store.

The official product release date is 9/22/08.

For more information, visit the MasterPlex QT v4.0 product information page.

MiraiBio has just released a Flash demo movie on doing absolute quantification with MasterPlex QT. This demo covers the following topics:

1. Opening up a raw data file
2. Marking the plate
3. Entering standard values (for replicate standard wells that are side-by-side)
4. Entering standard values (for replicate standard wells that are stacked on top of each other)
5. Selecting the model equation along with the weighting algorithms
6. Calculating and viewing the concentrations and standard curves
7. Saving your settings in a template
8. Applying your template file to new plate files

This demo movie will serve as a great quick start guide for new users.

For more information on MasterPlex QT, please visit the MasterPlex QT overview page or download the FREE trial.