A micro-ring resonator as a DEP electrode: Bioparticle interaction phenomena and sensing integration issues

• Applicant: Dr. Anders Henriksson
• Subject Area: Microsystems ; Biomedical Systems Technology
• Term: from 2018 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 404251289

Modern trends in bioanalytical research point toward interdisciplinary approaches and a miniaturization and digitalization that allows effective integration with modern microelectronics, and thus enable label-free automated sensors with highly specific molecular interactions. In the proposed project, photonic micro ring resonance sensing and dielectrophoresis (DEP) are fused together into a single microchip and combined with innovative click-based surface chemistry to control and examine molecular interactions and mass transfers. Innovative conducting mirroring resonators with retained optical properties and only a few 10 µm diameter will be used as the DEP electrode that focus the desired bioparticles directly onto the sensor surface. This will be realized thanks to a unique interdisciplinary constellation of BVT and IHP, allowing the production of professional semiconductor technology adapted to biological systems.The proposed portable device may bypass current limitation in biosensing attributed to molecular diffusion, thus allowing faster measurements and the potential to reach so far unattained sensitivities. Micro-ring resonance sensing may in addition allow to monitor the fundamental interaction between the free bioparticles and the electric field as well as to extract its dielectric properties. Further, by exciting the silicon micro-ring with TE and TM polarization it is possible to monitor structural changes of the immobilized probing molecules such as monolayer stretching and bending as well as induced conformational changes.The ability to focus bioparticles onto a single spot of an electrode will also be applied to explore and optimize innovative surface functionalization strategies and new methods for patterned immobilization of bioparticles. Our ambition with this project is not only to develop a new innovative sensor with extraordinary sensitivity but to lay a solid foundation, theoretically and practically aiming to simplify future integration of dielectrophoresis in molecular sensing.

• DFG Programme: Research Grants
• Co-Investigators: Professor Dr. Mario Birkholz, Ph.D.; Professor Dr. Peter Neubauer