The ERC ADG “Engineering of biomimetic surfaces – Switchable micropatterns for controlled adhesion and touch” (SWITCH2STICK) has developed micropatterned polymer surfaces for innovative adhesive functions without glues, based on the “gecko adhesion principle”. While robotic applications were originally in the focus of these developments, a radically new application field of these microstructures will be taken to the initial steps of application and subsequent commercialization: the repair of injuries of the human tympanic membrane. Tympanic membrane damage is a frequent medical affliction, affecting over 30 million patients worldwide each year. It results in hearing loss, associated with a dramatic impact of the patients’ quality of life and a significant healthcare burden. Our invention suggests a new therapeutic option to replace conventional therapies: Wound management with a novel gecko-inspired surface structure. In collaboration with clinicians, the feasibility of the new technology has been demonstrated. When designed for interaction with skin, our surfaces cling reliably to mouse ear drums for up to 28 days. In addition to the adhesive function, they provide support for cell growth and proliferation and allow the option of local drug delivery due to the micropattern. Besides detailed market analyses and dissemination, activities in the proposed project range from a technical and pre-clinical validation in an animal model to establishing an IPR strategy and an initiation of the medical product certification. Our invention will overcome several critical limitations of existing solutions. Besides ear-drum repair, the project enables a wide field of additional medical applications ranging from electrode fixation to the fitting of wearable healthcare electronics. This PoC project is therefore to be seen as a preparatory step for exploring the market potential of various micropatterned medical surfaces and preparing a solid commercialization in this field.

Today, most electronics and robots are based on solid metals and semiconductors. This project aims at “Electrofluids” that conduct electrons while flowing as liquids. Because liquids have virtually no yield strength, they are ideal materials to replace solid metal leads in truly soft devices. ELECTROFLUID uses highly concentrated suspensions that are liquid in a wide temperature range. Transient conductive networks in suspended particles of commonly used conductors provide high level of electronic conductivity at the viscosities required for soft electronics and robots. They contain common conductive materials such as carbon, silver, gold, and copper and do not require specialized low-melting alloys of gallium or other expensive elements. In order to create stable Electrofluids with large conductivity at low viscosity with tuneable rheology, I study the interplay between particle-particle friction, contact resistance, percolation, bulk resistance, and suspension viscosity. I use both custom-synthesized and commercial particles in a size range of tens of nanometres to few microns and with different shapes, modify their surfaces with conventional and pi-conjugated surfactants, and formulate concentrated suspensions that exhibit large conductivity at low viscosity. The combination of different particle sizes, shapes, and fluids enables tuning the properties of the fluid towards specific application cases, for example to create highly flexible leads for logic signals versus high-power connections for the connection of actuators. The fluids will be encapsulated in elastomer tubes or micropatterned surfaces as they are commonly used in stretchable electronics. The specific aims of the project are: (i) to design highly concentrated suspensions that form transient percolating networks, (ii) to use this knowledge and synthesize fluids with tuneable electrical conductivity at low viscosity, (iii) to demonstrate that Electrofluids can be curtailed for particular applications.

Mechanical forces drive fundamental physiological functions in living organisms, yet it remains unclear how forces are transduced into intracellular biochemical signals. Mechanotransduction is a tightly regulated process, and its disruption often results in pathologies including tumorigenesis, chronic inflammation and fibrotic conditions. Crucially, recent studies have shown an important relationship between abnormal fibrosis and altered patterns of focal adhesion kinase (FAK) activity and cell adhesion. Prof. del Campo laboratory has pioneered the use of photo-triggerable ligands to spatiotemporally control cell adhesion and recently, Prof. García has demonstrated in vivo that spatiotemporal control of cell adhesion modulates fibrosis. In addition, Prof. García has demonstrated a strong relationship between cells adhesive force generation and FAK activation at individual focal adhesion (IFA). Despite the importance of FAK signalling in cancer and other pathologies, the mechanistic link between the FAK activity at individual focal adhesions and fibrosis remains elusive. To close this gap in our knowledge, there is a need to develop technologies capable of recapitulating dynamic force transmission at individual focal adhesions. This project aims to elucidate the molecular events that regulate FAK activity during force transmission and sensing of mechanical force at individual focal adhesions. I will combine novel molecular devices, light-activated cell-specific adhesive ligands and microscopy tools to in situ apply controlled forces at individual FA and measure cell responses in 2D, 3D and in vivo contexts. Importantly, FAK loss- and gain-of-function experiments will provide the functional importance of FAK during mechanotransduction. The fundamental investigation of mechanotransduction events will greatly advance our understanding of cell biology and inform future targets for fibrosis therapy, as mechanical forces is a driving factor in fibrosis progression.

Since Adam and Eve’s infamous apple, gripping, handling and releasing objects has been a thoroughly human activity: the hand and fingers combine muscular action with sensing, complemented by feedback from visual monitoring. Modern automation technology, e.g. in production and micro assembly lines, is now facing the challenge of manipulating of extremely small objects, with dimensions typically smaller than the width of a human hair. Existing gripping technologies are running out of steam in this range: controlled handling is either impossible by conventional processes such as suction grippers, or decreased reliability leads to low yields and productivity. Industry is urgently looking for new handling concepts and this trend is predicted to intensify after the CORONA crisis when automation will gain in importance for ensuring reliable production. The technology developed in the researcher’s original ERC Grant SWITCH2STICK turned out to be ideally suited for this purpose. Eduard Arzt’s team successfully created the fundamentals and first prototypes of gecko-inspired surfaces with switchable adhesive functions. As the technology is bioinspired it is highly energy-conserving and sustainable. Now, increased reliability during the handling process has become possible. Using novel materials for the surface structures, the research group has demonstrated in their lab the gripping of objects down to dimensions below the thickness of human hair. This function of micropatterns to handle microobjects reliably is the groundbreaking new idea which will be validated for market readiness in this proposal. Considering that the relevant industrial sector of automated micro assembly is already a multi-billion Euro market with a strong growth rate, a new solution is expected to have a large economic impact, especially in Europe where many market leading automation companies are based.