Lab on a Chip: Scandinavia

Thomas Laurell

Thomas Laurell received his PhD in 1995 at Lund University on the development of a portable glucose monitoring system using porous silicon enzyme microreactors. Laurell became an associate professor in 1998 at Lund University performing research on microfluidics and protein analysis by mass spectrometry. He has been Professor in Medical and Chemical Microsensors since 2000 and has a focus on lab-on-a-chip technologies in biomedicine at the division of Nanobiotechnology. Laurell was appointed Distinguished Professor at Dongguk University, Dept. Biomedical Engineering, Seoul, Korea, in 2009. Laurell is currently heading an applied nanoproteomics laboratory at the Biomedical Centre in Lund. Since 2009 he has been the director of the clinically oriented research environment CellCARE at Lund University. Laurell was appointed President of the Chemical and Biological Microsystems Society, CBMS, in 2009.

Jörg P. Kutter

Professor Dr Jörg P. Kutter received his B.S in chemistry in 1991 and his Ph. D. in analytical chemistry in 1995, both from the University of Ulm, Germany. He was a postdoctoral research fellow in the Laser Spectroscopy and Microinstrumentation Group at Oak Ridge National Laboratory, USA, developing microchip-based analytical tools. In 1998, he joined the Department of Micro and Nanotechnology of the Technical University of Denmark (DTU). In 2006, he was appointed Professor in experimental lab-on-a-chip systems at DTU and is group leader of the ChemLabChip Group. Dr Kutter has extensive experience in leading scientific projects, has supervised and co-supervised 20 PhD students, has more than 100 international peer-reviewed publications and books/book chapters, and is involved in several international conference committees, advisory boards and professional organizations.

Examples of early Scandinavian papers on microfluidics, miniaturized sensors and integrated systems date back to the early to mid-90s.^1–5 At that time, the emergence of lab-on-a-chip systems and micro-Total-Analysis-Systems was driven on the one side by analytical chemists trying to incorporate and miniaturize all steps of an analytical process. Here, separation methods and, in particular capillary electrophoresis, played a central role in those early days. Coming from another angle, engineers with experience in semiconductor technology, microfabrication and fluid mechanics were also investigating novel ways to manipulate fluids in confined spaces and apply this to problems in chemistry, biology and medicine. Both “camps” have a strong tradition in Scandinavia, which is why it is hardly surprising that Scandinavian researchers at academic institutions, as well as in companies, were involved in the establishment of the field of lab-on-a-chip from the get-go.

Across the Scandinavian territory a number of nucleation points can readily be found. In particular, the Uppsala region in Sweden pioneered early developments in industry, headed by Pharmacia Biotech, which had a research unit at the time doing very early developments in hot embossed polymer microchannels for microfluidic manipulations. This later gave rise to Gyros AB, developing centrifugal microfluidics-based assays and sample preparation. Also, the SPR technology and the commercialization of immuno affinity interaction instrumentation was pioneered in Uppsala by Biacore. Since then, many other strongholds, from Aalto University in Finland to the centers in the Oslo area and Trondheim in Norway, to KTH, Chalmers, Linköping and Lund in Sweden and on to DTU in Denmark, have been established and continue to thrive.

An important milestone for the consolidation of LOC research in Scandinavia and an acknowledgement of the research quality in the region was certainly the MicroTAS conference in Malmö in 2004, the major international conference on miniaturized systems for application in the life sciences, at that time attended by about 750 people.

In this themed issue, we are proud to feature current research from various Scandinavian labs. The wide spectrum of research topics covered reflects the width of the LOC field as it has developed over the last 20 years. The eight featured papers describe theoretical and basic aspects of microfluidics, as well as applications into biochemistry, cell biology and environmental monitoring. Even more exotic topics, such as microfluidic electronics, are touched upon as well.

We start off with a Communication where Ainla et al. (DOI: 10.1039/C2LC40563F) describe a multi-functional pipette allowing electroporation of a single cell and at the same time delivery of different compounds in a controlled way to the interior of the cell. A method to enrich dilute cell and particle suspensions by acoustophoresis is shown by Nordin and Laurell (DOI: 10.1039/C2LC40629B). Up to 200-fold enrichment was achieved using multistage acoustophoretic focusing. An in-depth theoretical study into processes involved in using acoustic forces to manipulate cells and particles in microchannels is provided by Muller et al. (DOI: 10.1039/C2LC40612H). A numerical model accounting for the effects of the predominant forces is presented. Brøgger et al. (DOI: 10.1039/C2LC40554G) have used centrifugal microfluidics to handle DNA and study chromosomal translocation, demonstrating advantages of their approach over the still predominantly used FISH assays. Ion transport facilitated by membrane proteins was studied using lipid bilayers and a microfluidic setup by Ohlsson and co-workers (DOI: 10.1039/C2LC40518K). With the ability to quickly exchange minute liquid volumes, transport phenomena could be investigated with excellent time resolution below 100 ms. Chip designs and novel fabrication approaches to realize particle focusing using inertial (high Reynolds number) fluidics in straight channels is demonstrated by Hansson et al. (DOI: 10.1039/C2LC40241F). Their approach points to the possibility to easily and inexpensively fabricate devices with high throughput for filtration applications. A straightforward microfluidic chip design for gold nanoparticle-based fluorescence detection of mercury is shown by Lafleur et al. (DOI: 10.1039/C2LC40543A). The same technique is readily adaptable to carbamate pesticides as well and revealed excellent detection limits. Finally, Jeong et al. (DOI: 10.1039/C2LC40628D) describe the use of the ever popular PDMS as the basis for developing microfluidic stretchable electronics. This technology has many interesting applications and the authors demonstrate wearable RFID tags.

We would like to thank our Scandinavian colleagues for their contributions to this themed issue, and Harp Minhas and his team at the RSC for giving us the opportunity to co-edit this themed issue and for their support at all stages of putting everything together.

References

1. G. Stemme, G. Kittilsland and B. Norén, Sensors and Actuators A, 1990, 21-23, 904–907.
2. J. Branebjerg, O. Søndergård, N. G. Laursen, O. Leistiko and H. Soeberg, Technical Digest IEEE Transducers, 1991, 91, 41–44.
3. P. Gravesen, J. Branebjerg and O. Søndergård Jensen, J. Micromech. Microeng., 1993, 3, 186–182.
4. T. Laurell and L. Rosengren, Sens. Actuators, B, 1994, 19, 614–617.
5. U. D. Larsen, G. Blankenstein and J. Branebjerg, Proceedings Transducers ’97, 1997, 1319–1322.

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