FAST BREAKING PAPERS - 2008

Why do you think your paper is highly cited?

SPR-based immunoassay is a highly demanding and rapidly growing research area around the world. Indeed, ours was an invited review paper for the special issue of the Sensors and Actuators B Journal on its celebration of its 25th year of publication. While accepting this invitation, I had a clear vision that this review paper should represent a straightforward, systematic, and well-organized information source providing a wealth of information on the state-of-the-art regarding the principle and application of SPR immunosensors.

I believe that our review article provided all the necessary information for all kinds of research conducted within this area. Through offering extensive information pertaining to the biomedical, food, and environmental applications of SPR immunoassays, this paper has received extensive attention from researchers around the world. Thus, it has been highly downloaded and cited. At this time, I'd like to thank one of my co-authors, Dr. Dhesingh Ravi Shankaran, for his significant contributions to the final paper.

Does it describe a new discovery, methodology, or synthesis of knowledge?

This review article provides the basic methodology while outlining current trends and challenges in SPR-based immunoassays across a variety of application areas.

Would you summarize the significance of your paper in layman's terms?

SPR immunoassays offer exceptional performance capabilities with respect to sensitivity, specificity, speed, and multianalyte detection in complex analytical matrices. Advancements in the technology of antibody production and signal transduction provide a promising scope for SPR immunosensors to lead the way to the next generation of biosensors.

The important aspects investigated by the use of SPR include protein binding, association/dissociation kinetics, and affinity constants, which contribute to wider application areas such as that of molecular engineering, food analysis, clinical diagnosis, proteomics, environmental monitoring, bacteriology, virology, cell biology, drug discovery, and warfare detection.

This review highlights the current state-of-the-art in SPR immunosensors and briefly outlines important issues regarding the development of SPR immmunosensors; such as the preparation of biomolecules, sensor fabrication, non-specific adsorption, surface regeneration, and detection principles.

Particular emphasis is given to the indirect competitive immunoassay principle, which is compatible and highly promising for the detection of small analytes with enhanced sensitivity. We have also provided a detailed discussion on the application of SPR immunosensors for biomedical, environmental, and food analysis along with tables containing the characteristic features and scope of each immunosensor.

How did you become involved in this research, and were there any problems along the way?

Indeed, my main research area has been that of solid-state gas sensors, in which I have been working for the past three decades. In addition, biosensor and super capacitor investigations are also progressing among my research group.

I had started working on SPR-based immunosensors 15 years ago. As a matter of fact, we were the first to actually apply the principle of indirect competitive inhibition to an immunosensor for the detection of small molecule compounds (drugs). Since then, we have demonstrated this methodology in detecting a variety of small molecular biomedical and environmental compounds with remarkable sensitivity and selectivity.

In my research group, we have not had any particular problems in our investigations. However, several challenges remain to be overcome in SPR immunosensors, such as the development of portable systems for direct analysis, multi-channel and multi-functional immunosystems for the simultaneous analysis of multiple analytes in complex matrices with enhanced sensitivity, and also selectivity using minimal sample volume. Of course, these challenges exist for all researchers within this field. I am happy to mention here that we have already demonstrated the use of portable SPR systems for the detection of small molecule compounds and it can be said that further advancements are currently under way.

Where do you see your research leading in the future?

Recent trends demonstrate an aggressive growth in the basic research as well as application of SPR immunoassays. I believe that this research area is one of the most demanding among all areas of science and technology. Hence, in the future, rapid growth can be expected across all of these areas. The immediate future should involve the development of highly simplified miniaturized systems for direct analysis of any analyte in its complex matrices, also without prior separation and with only a very small sample volume.

In a simple way, the analysis system is expected to be highly user-friendly, such as the use of a personal diagnostic, hand-held explosive detector, bar-coded food analysis systems, etc. Current and future research in my laboratory will be along similar lines of concentration. Currently, the immediate target for my research group is the development of "lab-on-a-chip" systems for the high-performance sensing of small molecule compounds.

Do you foresee any social or political implications for your research?

SPR-based immunosensors have become significantly more important in various areas, among which are environmental monitoring, food analysis, clinical diagnosis, molecular engineering, and homeland security. Essentially, these factors govern the quality of life around the around. As a matter of fact, providing a better quality of life is of primary importance to almost any government around the globe. In this regard, I believe that this research has extensive social and political implications.

Norio Miura, Ph.D.
Professor
Art, Science and Technology Center for Cooperative Research (KASTEC)
Kyushu University
Kasuga-shi, Fukuoka, Japan

Keywords: Norio Miura, surface plasmon resonance immunosensors, SPR immunoassays, SPR immunosensors, SPR-based immunoassays, multianalyte detection, kinetics, affinity constants, molecular engineering, food analysis, clinical diagnosis, proteomics, bacteriology, virology, cell biology, sensor fabrication, surface regeneration, portable SPR systems.