Minute structures for maximum efficiency

Growing demand for decentralized diagnostics

These miniature laboratories, called Lab-on-a-Chip (LoC), are generally flat, injection molded parts made from plastic with minute channels whose diameter is generally smaller than a human hair. Optical, fluorescent or electrochemical sensors are integrated in the chips, depending on their intended application, which react to target molecules in the sample. The chips can also contain micro-pumps and other mechanical components. A film layer is applied to seal the open-top chips. This layer requires a special surface in order to allow the minute amount of fluid to pass through the microcapillaries. Just like the special PLEXIGLAS® and EUROPLEX® films from Röhm GmbH which the Business Unit Acrylic Products will present at Compamed 2021.

Crystal clear and heat resistant - COC films from Röhm for microfluidics

“Microfluidics is a particularly fascinating application area for our special films, and the market demand for components used in decentralized diagnostics is increasing,” says Marc von Locquenghien, Product Manager Films at Röhm. The EUROPLEX® COC Film is ideal as a sealing film for lab-on-a-chip applications. It is applied to the main body either via ultrasound welding, laser welding or thermobonding.

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This film is characterized by outstanding transparency, low inherent fluorescence and low birefringence. These properties are vital to ensure error-free evaluations using spectroscopy. In addition, the material is also biocompatible and can be sterilized, as it is resistant to acids and alkalis, as well as numerous solvents including acetone, ethanol, isopropanol and ethyl acetate. EUROPLEX® COC Films also display high thermal resistance. Depending on the variant, the glass-transition temperature is 142°C. “This is a vital factor, as samples such as those used in PCR tests, are repeatedly heated to 100 degrees Celsius and then cooled over a short period of time in order to duplicate the sample material,” explains von Locquenghien.

Lab-on-a-chip applications are used for point of care diagnostics which provide the tests to the people directly. Patients no longer have to be taken to a clinic and time-consuming transport and manual test preparation in the lab are also no longer necessary. Instead, a myriad of chips with the sample material and mobile analysis devices are used, enabling results within 30 to 60 minutes. “All analysis steps can be combined in a single device and are efficiently completed on a tiny surface,” clarifies von Locquenghien.

Why microfluidics will become increasingly important in the future

Dr. Jana Schwarze, Project Manager for Microfluidics at the IVAM Microtechnology Network explains why these tiny structures provide the greatest effect in diagnostics: “Firstly, the required sample size is smaller. Other significant benefits include a shorter analysis duration, greater control and resolution, as well as higher sensitivity and protection against contamination.”

She adds: “Small and compact equipment generates fewer costs and can be handled easily and safely.” The expert is convinced that microfluidics will play a greater role in medical diagnostic processes in the future, as it provides virtually unlimited application options. She currently sees great potential when it comes to analyzing the vaccination status prior to booster vaccines against SARS-CoV-2, as well as for mobile PCR tests. Schwarze also expects pioneering innovations when it comes to biosensors and Organ on a Chip systems as alternatives to animal testing.

Innovative materials expand the application range

The development of innovative materials and processing methods is helping to advance the field of microfluidics. Röhm is also continuing the development processes of its PLEXIGLAS® and EUROPLEX® film products for medical technology. Its most recent product development is a multi-layer film made from EUROPLEX® COC and a thin sealing layer. It enables analysis chips to be sealed at lower temperatures, thereby not only protecting the fine components in the miniature laboratories, but also accelerating the entire sealing process.