Microfluidic device for the rapid coating of magnetic cells with polyelectrolytes

We demonstrate a rapid method of coating a layer of polymer onto magnetically modified yeast cells, so-called “cyborg cells”, in continuous flow within a microfluidic chamber. Laminar flow streams of polyelectrolyte and washing buffers were generated across the chamber, and the magnetic cells were deflected sequentially through the co-flowing streams via an external magnet, allowing polyelectrolyte deposition onto the cells immediately followed by the washing step, all in less than 90 s. This simple deposition technique shows promise for the functionalization of such cyborg cells for applications including bioelectronics, bioanalysis, and toxicity screening, while the addition of more reagent streams would enable the fabrication of multilayered capsules.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A microfluidic method for the rapid coating of cyborg cells was investigated. ► Magnetic yeast cells were deflected through a laminar stream of polyelectrolyte. ► Fluorescent labelling and washing of the cyborg cells was achieved in <90 s. ► Simple setup consisting of a straightforward chip design and permanent magnet.