Abstract: There is provided a device, system and method for recovering magnetically tagged target cells from a fluid collection of cells. The device comprises a magnet plate having an array of micro-magnets and a modular chip releasably coupled to the magnet plate. The modular chip has a flow chamber and a plurality of flow rate-reducing structures. The magnetic field produced by the array of micro-magnets cooperates with the flow rate-reducing structures to define a capture zone in the vicinity of each structure. The magnetic field is sufficient to overcome drag force on the target cells to promote capture of the target cells in the capture zone. Separation of the modular chip from the magnet plate allows for recovery of the captured target cells from the modular chip.

Abstract: A biosensor comprising an electrode and inverted molecular pendulums (iMPs) is described. Each IMP includes a linker bound to the electrode, and an analyte receptor and a redox reporter both bound to the linker. The redox reporter is reactive at positive potential when the linker presents a net negative charge and reactive at negative potential when the linker presents a net positive charge. Upon application of an electric field, the biosensor is characterized by an iMPs unbound state, where no analyte is bound to the receptor, at which the iMPs are displaced towards the electrode and electron transfer from the iMPs towards the electrode occurs at an unbound electron transfer rate, and an iMPs bound state, where the analyte is bound to the receptor, at which the iMPs are displaced towards the electrode and electron transfer from the iMPs towards the electrode occurs at a bound electron transfer rate.