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Weekly question

Model question 1

Question: Which analysis model should you use for this interaction?

A: 1:1 interaction
B: 1:1 interaction with mass transfer
C: bivalent analyte interaction
D: 1:1 interaction on decaying surface

Equilibrium constant

Is the equilibrium dissociation constant all what matters?

In kinetics there seems to be a race for the best (lowest in this context) equilibrium dissociation constant (KD) there is. Interactions are compared by their equilibrium dissociation constant and that is it. Similarly often only the IC50 of a system is given while the full kinetics are not well established.

In my opinion, reporting a single value for a kinetic interaction is hiding all the other information present in the measurements between two or more components.
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Improving protein quality

With regular maintenance your instrument is in perfect order. In addition you make the best, clean and degassed buffers. But what about the proteins you use? Are they of the best quality? And this new batch is the same as the previous, you are sure of that?
Is your protein affected by the buffer and immobilization conditions used? Your assay problems might be caused by poor protein quality!
Luckily there is an easy and fast way to check the integrity of your proteins. Nanotemper Technologies provides various instruments to check your protein quality, all using a minimum of sample. .
SPR is not an Art

SPR is not an Art!

Surface Plasmon Resonance (SPR) seems to be difficult for many people. Judging on the literature many of you are struggling to get nice sensorgrams with easy to fit curves. However, SPR is straightforward when you know what you are doing. Consequently, you have to learn how SPR works, how to perform an experiment and how to analyze it. So what are the key parts of a proper SPR experiment?
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Blog of Ryan Denomme

Ryan Denomme of Nicoya publishes a nice blog about SPR and related topics. For instance about preserving precious sample by optimizing preconcentration and immobilization or what the difference is between SPR and LSPR.
Definitely worthwhile to check this blog!


More Blog Posts

Read more blog posts by following the next link.


The KD assistant is a small program to assist with the optimization of kinetics runs. The program can calculate the maximal analyte concentration to be used from one manual analyte injection. The input consists of the initial binding rate (slope), the response of the analyte injection and the analyte concentration. The program deals also with the capturing level of the ligand and adjusts the analyte concentration accordingly. Goto Software


The SPR-forum is dedicated to the combination between SPR and biomolecular interactions. There are many questions asked and answered so browse through the topics.
Feel free to post your questions about the technology, instruments or experimental set-up.


The SPR-Simulation software is a standalone application to simulate kinetic interaction curves. The program draws the curves after the input of the kinetic rate constants, the analyte concentration and the association and dissociation times.
Other features are the simulation of equilibrium sensorgrams, mass transport, decaying surfaces and plotting an overlay over an imported sensorgram figure.


Your Help

Your help is appreciated!. Give your feedback about this website, tips for better experiments or report interesting links. Maybe you have nice tips for every body or you can contribute in a more substantial way to the SPR-pages. Check out the forum for questions and answers.

Web links

Look at the many books, suppliers, machines, software and other links!? Did you look at the FAQ and download pages? You will find a lot of interesting stuff there.
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The SPRpages are not affiliated to any company or institute. For the maintenance of the SPRpages we rely on the donations and the sales of the SPRpage book and the SPR-simulation program. Therefore, any donation is appreciated.

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clean immobilization stabilization association steady state dissociation regeneration analysis