Self-rolled-up microtube technology for cellular outgrowth guidance and monitoring

Abstract

The evolution and optimization of self-rolled-up membranes (s-RuM) has been taking place over the past two decades at a fervent pace. This progress has culminated in a rolled-up structure that is not only insulating, but transparent and biocompatible, allowing it to be integrated into conductance, photonics, and strain-based sensor systems. These microtube-forming membranes are easily fabricated and can be integrated into a microfluidic channel (or become the channel itself) which can be easily integrated into an intravenous or catheter tube for diagnostics. In this dissertation, the advantages of silicon nitride (SiNx) based s-RuMs are investigated and outlined, showing that insulting properties allow conductance-based and capacitance-based biosensors to be easily integrated into the same channel. In addition, the metal added to this structure can act as a surface-enhanced Raman spectroscopy (SERS) sensor. Further, analyte size exclusion is possible via diameter variation and surface functionalization, adding another degree of precision. Extending this platform beyond sensing to cellular growth guidance, we find properties unique to this material system and superior to existing platforms. The SiNx s-RuM platform can be used for potential applications ranging from sensing to culturing, from disposable electronics to implants, and from brain-computer interfaces to stem-cell functionalized stints.