- Protein-protein interactions were analyzed on OpenSPR™, Biacore™ and IBIS™ instruments
- Kinetic analysis was used to determine the on rate, off rate, and affinity constant of the interaction of 2 different ligands with an analyte
- All three instruments produced acceptable kinetic constants within the expected error range for these experiments, validating the OpenSPR™ instrument against other commercial SPR equipment
OpenSPR is a benchtop surface plasmon resonance (SPR) solution which provides researchers with the ability to complete in-depth label-free binding kinetics in their own lab. When searching for an SPR solution, researchers have to choose from various performing tools for different applications. Addressing the performance of the tools and establishing their consistency and accuracy is important when making a purchasing decision. We always get asked about when we will create a comparison study between our OpenSPR and other more expensive commonly used tools and so we are responding with this great comparison study. In this study, we will investigate the binding kinetic results of protein-protein interactions and how they compare between OpenSPR, Biacore T100 and IBIS MX96 SPR systems.
Analyzing Protein-Protein Interactions with all Three Systems
There’s no better way to compare the instruments than to have Dr. Olan Dolezal from CSIRO independently create the biomolecular system and conditions for producing the experimental results for each system. The goal of the study was to produce useful information for researchers and industry experts that could put them in a better position to understand the capabilities of the OpenSPR. The kon, koff, and KD of two different protein ligand mutants (M1 and M2) to one protein analyte were determined and compared using kinetic analysis.
For those of you who are interested in knowing the materials and equipment used for the experimental procedure, take a look at our detailed technical note. But, let us get to the heart of the matter: how does OpenSPR compare to the Biacore and IBIS SPR systems?
Figure 1. Binding curves and kinetic analysis of M1 ligand on OpenSPR
Figure 2. Binding curves and kinetic analysis of M1 ligand on Biacore T100
Figure 3. Binding curves and kinetic analysis of M1 ligand on IBIS MX96
Table 1. Binding kinetics and affinity of M1 ligand
Table 2. Binding kinetics and affinity of M2 ligand
These two tables answer the question
The KD for M1 was found to be 5.7nM, 5.2nM, and 8.9nM on the OpenSPR, IBIS, and Biacore, respectively. The KD for M2 was found to be 0.54nM, 0.12nM, and 0.16nM on the OpenSPR, IBIS, and Biacore, respectively. The average KD was 6.61nM +/- 2.0 for M1 and 0.27 +/-0.23nM for M2.
As shown in Tables 1 and 2, all three instruments produced acceptable kinetic constants within the expected error for these experiments. A Global Benchmarking study went into detail on the level of error that can be expected in kinetic experiments with different users and different instruments, showing that for one protein-antibody system a KD of 0.620nM was obtained with an error +/- 0.980nM . Such errors can arise from differences in conditions, user errors, and equipment differences. If you take a deeper look into the technical note, you’ll notice that the binding curves between the instruments all look comparable with similar signal to noise levels. The results of this study validates the OpenSPR against other commercial SPR equipment.
The OpenSPR is a very versatile and affordable system…Both graduate and undergraduate students have used the instrument to generate reliable data.
Now you have just learned how comparable the accuracy and high quality kinetics are between all three systems. In case you want to dive deeper, you can find the full application note here. But here’s the real takeaway: Most of you are probably individual researchers working on your own applications, or you may be an industry expert needing a compact yet comprehensive way to get real-time binding kinetics to gain traction on your important projects. In any case, the OpenSPR proves to be the best in this case because of four main benefits:
Avoid costly & inconvenient core facilities with our affordable benchtop solution
2. Real-Time Data
Publish faster with label-free binding kinetics & affinity data
Train anyone in your lab to become an SPR expert with our user-friendly solution
4. Low Maintenance
Forget about expensive service contracts so you can focus on your research