Integration of melt electrowritten microfibers with magnetoelastic sensors for continuous monitoring of cell growth†

Magnetoelastic sensors, which are wirelessly activated and interrogated via magnetic fields, have gained popularity for monitoring physical parameters such as mass loading and stress. The functionalization of the sensor surface has facilitated the development of biosensing devices with the capacity to monitor chemical/biological quantities such as liquid pH, bacteria, and cell growth in biological environments. In this study, melt electrowriting (MEW) is used for the first time to integrate user-defined microstructures onto the surface of magnetoelastic sensors, aiming to enhance their cell growth monitoring performance. Specifically, MEW is used to define specific topographies on the sensor surface, which enable custom control of attachment, distribution, and alignment of cells along the sensor surface. This technique holds potential for engineering tissues with predefined physical structures, as well as for the development of advanced monitoring systems for tracking the growth of adherent cells in real-time.