Fiber Based Devices for Sensing and Actuating Applications

Abstract

The importance of multifunctional smart medical devices increases constantly during the last decades, fuelled by socio - economic challenges such as population aging and high costs of the healthcare system. Consequently, numerous research teams are focused on developing such devices with multiple functionalities in terms of both diagnostic and therapeutical approaches.Wearables become ubiquitous since computing and communication devices got smaller and more powerful, new functions being constantly added to consumer products such as smart watches or fitness monitors. Physical or chemical parameters including pulse, blood pressure or oxygen saturation are easily measured. Employing complex architectures based on nanostructures and materials with tailored properties represents an important path in developing a new generation of wearable medical devices which may both monitor chemical parameters (sweat or blood composition) and deliver various therapies.The present report focuses on describing such architectures with the potential of incorporating both health monitoring, transdermal drug delivery and other therapeutic functions in a relatively straightforward manner. As functional elements microscopic fibers are employed as both electrodes for electrochemical sensors, as microscopic heaters for the drug delivery function or, as building blocks for other specific functions. The fibers are fabricated using electrospinning or centrifugal/force spinning and functionalization (e.g. electrical conductivity) is achieved through physical and electrochemical deposition. Therefore, the fibers can be covered with thin metal layers and rendered conductive, oxidic or polymeric layers making them responsive to various stimuli. Heating is achieved in a straightforward manner through Joule effect and the use of a temperature responding hydrogel enables a controlled release of specific drugs while simultaneously improving epidermal permeation.These fiber-based systems can be easily employed on cheap, biocompatible substrates such as paper or textile materials and therefore can be mass produced with reasonable costs leading to a new generation of medical devices with increased functionality.