Development of an Adhesive-less Bonding Method

Microfluidics Plates

Achieving High-Strength,
Pressure-Resistant Bonding Without Adhesive:
Senclear™ Multilayered Structure and Coluful™ Plates with Internal Columns

Solutions Based on Tried and Trusted Precision Processing Technology

All over the world, the number of people with, or at high risk of becoming afflicted with, diabetes or another lifestyle-related disease continues to climb, along with the costs of medical treatment. New devices are needed to aid new drug discovery and development, a process that takes a lot of time and considerable investment before approval is received, and to support innovative forms of medicine, such as applications of biotechnology. In the healthcare domain, Alps Alpine has introduced solutions to help meet this demand, applying many years of precision processing expertise relating to molds and molding to develop microfluidics plates; specifically, Senclear™ – a multilayer microfluidics plate structure – and Coluful™ – microfluidics plates with internal columns.

The two types of microfluidic device make it possible to create more compact systems and enable faster, more efficient testing and analysis. The solutions also make use of Alps Alpine’s very own innovative technology – a completely new method of microfluidics plate bonding.

High-Strength, Pressure-Resistant Bonding Without Adhesive

Alps Alpine’s microfluidics plates are made from cyclo-olefin polymer (COP), a resin-based plastic employed in lenses and other optical components. The material has properties similar to glass and is ideal for microfluidics plates. Its many advantages include low autofluorescence, excellent transmittance, low protein adsorption, high strength, disposability and high mass production viability. Bonding posed difficulties, however, given the hydrophobic nature of the molded surface. Industry players struggled to find an answer. Alps Alpine overcame this hurdle by developing its very own original bonding method.

Microfluidics plate bonded using original technology

SEM image of channel cross-section

Bonding of up to seven one-millimeter-thick COP plates is possible at any one time using this technique, the main feature being the realization of high bonding strength and pressure resistance without using an adhesive. If an adhesive were to be used and even just a tiny portion of its constituents separated and found its way into a specimen, toxicity and other factors would make an accurate measurement unobtainable. Alps Alpine plates bonded without adhesive are integrally joined, as if they were machined that way, so contamination is not a concern. Bonding strength is outstanding, with the ability to withstand 10MPa internal pressure while maintaining micron-level precision using advanced mold technology. Plates properly function as completely closed devices by not coming unstuck, breaking or leaking when carrying blood or other liquid specimens, thus upholding reliability in testing and analysis. Specializing in use of COP, an excellent material, Alps Alpine applied original technology to establish an industry-first solution.

Senclear™: Finding Use in Drug Discovery and Development and Innovative Medicine

Senclear™ microfluidics plates are devices enabling configuration of 3D microfluidic structures using microfluidic designs suited to each application and stacking of plates without adhesive. Processes to choose from, depending on the need, include mixing, synthesis, reaction, purification, separation, isolation, dispensing, extraction, concentration, amplification, dilution and detection. Electrical detection and measurement are also possible and involve embedding electrodes, insulators and protective layers inside the plates. Electrodes of carbon, platinum, silver and silver chloride can be deployed in extensive variations.
Senclear™ increases the speed and efficiency of testing and analysis. In the field of drug discovery, where considerable time and money is invested during the process from research and development to clinical trials and approval, Senclear™ helps to dramatically speed up and reduce the cost of translational research. Applications are also expected in innovative domains, such as regenerative medicine, involving iPS cells, and biopharmaceuticals.

Senclear™ multilayer microfluidics plate structure

Coluful™: Contributing to Smaller LC Systems and Preventive MedicineLC

Developed as one example of microfluidics plate deployment, Coluful™ plates have internal columns of the kind used in liquid chromatography (LC) systems for disease testing. The columns employ silica monoliths that were jointly developed with Kyoto Monotech Co., Ltd. While small, they create bigger cavities and a larger reaction surface area than existing granular materials, allowing them to function on a par with columns of large systems.

The plates enable testing, separation and analysis with just small samples and little reagent and solvent (buffers). Low fluid pressure of no more than 1MPa is also supported, realizing compact LC systems and faster testing. Column plates are a cartridge type for easy use and to enable automation of column replacement, previously performed manually by dedicated operators.

Alps Alpine has developed a compact, lightweight demo set of an LC system for disease testing that draws on the properties of Coluful™. Besides fitting columns, which were tubes in large systems, onto plates, the low fluid pressure properties of silica monoliths were used to realize a compact system capable of high-precision separation. With a footprint of around one fifth compared to existing systems and smaller volume (approx. one tenth), the system is a compact size allowing desktop installation. This makes it easier for local clinics and medical institutions to take on devices that previously only large organizations could use, thereby helping to extend the reach of preventive medicine for reducing medical costs.

Alps Alpine’s microfluidics plates realize high-precision point-of-care testing (POCT) and enable the quantitative diagnoses demanded by medical and pharmaceutical providers rather than qualitative diagnoses. These solutions expand future possibilities spanning from disease testing through to drug discovery and development to innovative medicine.