Photopolymer composite magnetic actuators for cell-based biosensors

Abstract

Abstract Nowadays, biosensors play a significant role in numerous areas and become part of our daily life. Here, electrochemical cell-based biosensors either use cells as a biorecognition element or they can monitor physiologically relevant information of cells. One of the greatest challenges for commercialization of cell-based biosensors comes from their main component, the cells, which are complex “living” systems and very vulnerable to environmental changes. Recently, to address this issue, a novel method, the cryopreservation of cell monolayers in a ready-to-use set-up, has been introduced. To further improve this method, herein we develop photopolymer-based magnetic composites (cell carriers) by photolithographically patterning different photopolymer resins (flexible resin and SU-8 photoresist) mixed with superparamagnetic iron oxide (Fe3O4) nanoparticles. These magnetic composites were designed for cryopreservation of cells grown on them in a ready-to-use concept: it allows the on-demand transfer of the actuators to the culture environment with integrated cell-based biosensor and positioning them close to the sensor surface or taking them away for the next cell population on another actuator by an external magnetic field. The key performance characteristics of the developed magnetic composites such as being able to control their location, mobility and orientation have been demonstrated in cell culture medium.