Sven Zinober

A novel concept for long-term pre-storage and release of liquids for pressure-driven lab-on-a-chip devices

On-chip storage of liquids is one of the major challenges of polymer-based lab-on-a-chip (LoC) devices. To ensure long-term storage of even highly volatile reagents in polymer disposal LoC cartridges, robust reagent storage concepts are necessary. Tubular bags, so-called stick packs, are widely used in the packaging industry. They offer sufficient vapor barrier properties for liquid storage. Here we present a polymer multilayer LoC-stack with integrated stick packs for the long-term storage of liquid reagents required for diagnostic applications. The storage concept fulfils two main requirements: firstly, the long-term storage of reagents in stick packs without significant losses or interaction with the surroundings and secondly, the on-demand release of liquids, which is realized by the delamination of a stick pack?s peel seam through pneumatic pressure. Furthermore, effects on the opening behavior of stick packs through accelerated aging were investigated after different storage conditions to proof repeatability. This concept enables on-chip storage of liquid reagents at room temperature and allows the implementation in different pressure driven LoC devices or similar applications. Since liquid storage in stick packs is well-established, emerging fields such as lab-on-a-chip combined with novel reagent release mechanisms should be of great interest for the commercialization of life science products.

The Way to High Volume Fabrication of Lab-on-a-Chip Devices—A Technological Approach for Polymer Based Microfluidic Systems with Integrated Active Valves and Pumps

We present a technology platform suitable for the mass production of laboratory-on-a-chip devices made of polymers with integrated active and passive components. The presented microfluidic platform with integrated valves and pumps for active flow management is realized with three layers consisting of two polymer parts separated by a thin elastic TPE (thermoplastic elastomer) membrane welded together in one step. The elastic TPE membrane acts as an integrated deflectable membrane layer between the two outer polymer layers, each made of a weldable thermoplastic polymer (polycarbonate). Valving is realized by applying pressure in a displacement chamber above a hydraulic channel causing the membrane to deform and to seal the channel. A pump is fabricated using a displacement chamber with a valve on the inlet and outlet. The presented components, namely valve and pump, show excellent behavior regarding response time, sealing quality, and pump rate needing only a low actuation pressure. The three-layer-stack is...