Switchable MEMS for integrated microfluidic platform

Microfluidics is a rapidly evolving technology that enables precise manipulation of small fluid quantities, from micro- down to picoliter. Although many functional elements have been successfully miniaturized and integrated in microfluidic chips, including electrical and optical sensors, the fluidic control still often relies on using external valves and pumps. These peripheral instruments are rather bulky and expensive, result in large dead volumes during operation, and -most importantly- cannot be scaled to large numbers. Hence, there is a strong need for more integrated solutions to meet the increasing demand for more complex workflows that require multiplexing and parallelization. In particular, the integration of microvalves is an utmost demand to enable integrated microfluidics. The applications for next generation microvalves are endless. For example, ingestible micro devices used for in-situ controlled drug release or in-situ monitoring of humans health, microreactors, next-gen DNA-sequencing and synthesis platforms for nanoparticles.  

This PhD topic will explore novel microvalve concepts by leveraging advanced MEMS/NEMS technologies compatible with state-of-the-art manufacturing processes. Today, PDMS-based pneumatic microvalves are most widely adopted in the academic field. The fabrication method involves soft lithography, which is difficult to implement at an industrial scale due to contamination issues, swelling, surface fouling or unstable surface properties. The microvalves based on classical MEMS technology exist, but typically require large dimensions, need high actuation forces, as well as have limited valve displacements prone to clogging. It is therefore necessary to develop novel valving working principles that is compatible with semiconductor production techniques. Further, the aim of this PhD is to build an integrated microfluidic platform initially to combine nucleic acid extraction and amplification. Such a platform would have applications not only in the field of next-gen DNA-sequencing, but also in sample preparation of single-cells, exosomes, and cell-free DNA. With this platform, we aim at providing a more automated, miniaturized and reliable sample preparation solution than the complex and highly manual sample handling currently being used in labs. 

The primary efforts of this PhD project will be the conception of the next generation microvalve. In this phase an interplay between material design (e.g. phase change materials/meta-materials), novel transduction types and physical processes are highly encouraged. Further multi-physical modeling and/or FEM simulation, design and validating the performance of microvalves are required. The next step is multiplexing a high density of microvalves on an active microfluidic platform. With which you will demonstrate the sample preparation application for DNA sequencing. The topic will be supervised and supported by a team of physicists, engineers, and biologists.