Surface Plasmon Resonance
Some 15 years ago, Biacore (www.biacore.com) introduced its technology for the label-free measuring of molecular interactions. Based on the principle of SPR, Biacore systems used gold-plated chips coated with a variety of matrices to which proteins or other interaction partners were attached. The total internal reflection of light from the underside of the glass chip was used to measure mass concentration-dependent changes in the refractive index of the bound complex.
At its inception, the first system complemented rather than competed with conventional ELISA detection due to its cost and complexity and was used for determining specificity, association and dissociation constants, affinities, and concentrations of interactants.
Earlier versions of the Biacore system were cumbersome and lacked sensitivity, but over the years new systems have been introduced and performance and ease of operation has substantially improved.
According to Gary Franklin, Ph.D., industrial sector specialist, “I think the ‘Biacore is difficult to use’ myth is a hangover from the early days. In the beginning there were a lot of unknowns in terms of assay design and specific application needs.”
Dr. Franklin added that the early software was an open tool, allowing scientists to examine the potential of unique ways of studying interactions. Consequently, there was less guidance available at that time, so there was a steep learning curve. In close collaboration with the early pioneers, the company gained enormous knowledge and experience, allowing them to develop better and much more user-friendly systems.
“Our Biacore T100 and Biacore A100 systems demonstrate the fruits of these labors,” Dr. Franklin continued. “They provide our highest levels of performance and productivity so far, and customer feedback regarding their ease of use and intuitive performance has been extremely positive.”
Biacore scientists have moved beyond providing SPR as a novel technology to developing a portfolio of systems aimed at a range of key applications. This includes a laundry list of high-quality, label-free interaction analysis systems for the life sciences, pharma/biotech, environmental sciences, and food analysis sectors. These advancements have been achieved through improvements in the user interface and built-in knowledge and guidance of the software.
The two systems, the A100 and the T100, do indeed offer many advantages over Biacore’s earlier models. The T100 is designed for early research through drug development and manufacturing quality control with software for assay development, analysis, and data evaluation and interpretation, whereas the A100 is designed primarily for higher throughput applications and multiplexed analyses, handling up to 3,800 interactions in 24 hours.
The A100 is flexible and can also be adapted for detailed characterization studies enabling integration into multiple phases of project pipelines, Dr. Franklin said. Moreover, the systems are designed for transition into regulated environments with optional packages that provide validation documentation and services.
“These improvements have made the system easier to use,” Dr. Franklin continued, “and this is something we are still striving to develop further as we progress. If you look at what we actually have been offering in the last few years, I think the difficult tag for Biacore is pretty harsh.
“Look at the other high-tech analytical systems, like mass spec and nuclear magnetic resonance. Are these really easy?” he asked. “But then, I suppose initial impressions take a long time to shake off in this business.”