Polymer Nanofiber Deposition in Lab-on-a-Chip Devices By Electrospinning

Electrospinning is a relatively cheap and simple method to deposit polymer nanofiber mats. The mats can be made of biocompatible materials and can be used to immobilize cells, proteins, enzymes or drug molecules on a surface or inside the fibers, such as in a microreactor inside a Lab-on-a-Chip (LoC) device. For self-contained, portable analytical devices, it is essential to have chemical and biological components immobilized in the device, so the system can be packaged and transported. We developed a method to repeatedly deposit a controlled amount of polylactic acid (PLA) nanofibers on a carrier substrate, which could then be sliced and transferred into a microfluidic chip. In this paper, we demonstrate repeatable PLA deposition on aluminum foils using a standardized electrospinning setup with humidity and temperature control. Furthermore, we demonstrate the deposition of PLA fibers with encapsulated biomolecules by mixing the lipase enzyme with the PLA precursor. Finally, we demonstrate the transfer of the enzyme-filled fibers into 3D printed microfluidic chips (a.k.a. electrospun microreactors) and evaluate flow characteristics of the created system.