Textination Newsline

A bandage that releases medication as soon as an infection starts in a wound could treat injuries more efficiently. Empa researchers are currently working on polymer fibers that soften as soon as the environment heats up due to an infection, thereby releasing antimicrobial drugs.

It is not possible to tell from the outside whether a wound will heal without problems under the dressing or whether bacteria will penetrate the injured tissue and ignite an inflammation. To be on the safe side, disinfectant ointments or antibiotics are applied to the wound before the dressing is applied. However, these preventive measures are not necessary in every case. Thus, medications are wasted and wounds are over-treated.

Even worse, the wasteful use of antibiotics promotes the emergence of multi-resistant germs, which are an immense problem in global healthcare. Empa researchers at the two Empa laboratories Biointerfaces and Biomimetic Membranes and Textiles in St. Gallen want to change this. They are developing a dressing that autonomously administers antibacterial drugs only when they are really needed.

The idea of the interdisciplinary team led by Qun Ren and Fei Pan: The dressing should be "loaded" with drugs and react to environmental stimuli. "In this way, wounds could be treated as needed at exactly the right moment," explains Fei Pan. As an environmental stimulus, the team chose a well-known effect: the rise in temperature in an infected, inflamed wound.

Now the team had to design a material that would react appropriately to this increase in temperature. For this purpose, a skin-compatible polymer composite was developed made of several components: acrylic glass (polymethyl methacrylate, or PMMA), which is used, for example, for eyeglass lenses and in the textile industry, and Eudragit, a biocompatible polymer mixture that is used, for example, to coat pills. Electrospinning was used to process the polymer mixture into a fine membrane of nanofibers. Finally, octenidine was encapsulated in the nanofibers as a medically active component. Octenidine is a disinfectant that acts quickly against bacteria, fungi and some viruses. In healthcare, it can be used on the skin, on mucous membranes and for wound disinfection.

Signs of inflammation as triggers
As early as in the ancient world, the Greek physician Galen described the signs of inflammation. The five Latin terms are still valid today: dolor (pain), calor (heat), rubor (redness), tumor (swelling) and functio laesa (impaired function) stand for the classic indications of inflammation. In an infected skin wound, local warmth can be as high as five degrees. This temperature difference can be used as a trigger: Suitable materials change their consistency in this range and can release therapeutic substances.

Shattering glove
"In order for the membrane to act as a "smart bandage" and actually release the disinfectant when the wound heats up due to an infection, we put together the polymer mixture of PMMA and Eudragit in such a way that we could adjust the glass transition temperature accordingly," says Fei Pan. This is the temperature, at which a polymer changes from a solid consistency to a rubbery, toughened state. Figuratively, the effect is often described in reverse: If you put a rubber glove in liquid nitrogen at –196 degrees, it changes its consistency and becomes so hard that you can shatter it like glass with one blow.

The desired glass transition temperature of the polymer membrane, on the other hand, was in the range of 37 degrees. When inflammation kicks in and the skin heats up above its normal temperature of 32 to 34 degrees, the polymer changes from its solid to a softer state. In laboratory experiments, the team observed the disinfectant being released from the polymer at 37 degrees – but not at 32 degrees. Another advantage: The process is reversible and can be repeated up to five times, as the process always "switches itself off" when it cools down. Following these promising initial tests, the Empa researchers now want to fine-tune the effect. Instead of a temperature range of four to five degrees, the smart bandage should already switch on and off at smaller temperature differences.

Smart and unsparing
To investigate the efficacy of the nanofiber membranes against wound germs, further laboratory experiments are now in the pipeline. Team leader Qun Ren has long been concerned with germs that nestle in the interface between surfaces and the environment, such as on a skin wound. "In this biological setting, a kind of no man's land between the body and the dressing material, bacteria find a perfect biological niche," says the Empa researcher. Infectious agents such as staphylococci or Pseudomonas bacteria can cause severe wound healing disorders. It was precisely these wound germs that the team allowed to become acquainted with the smart dressing in the Petri dish. And indeed: The number of bacteria was reduced roughly 1000-fold when octenidine was released from the smart dressing. "With octenidine, we have achieved a proof of principle for controlled drug release by an external stimulus," said Qun Ren. In future, she said, the technology could be applied to other types of drugs, increasing the efficiency and precision in their dosage.

The smart dressing
Empa researchers are working in interdisciplinary teams on various approaches to improve medical wound treatment. For example, liquid sensors on the outside of the dressing are to make it visible when a wound is healing poorly by changing their color. Critical glucose and pH values serve as biomarkers.

To enable bacterial infections to be contained directly in the wound, the researchers are also working on a polymer foam loaded with anti-inflammatory substances and on a skin-friendly membrane made of plant material. The cellulose membrane is equipped with antimicrobial protein elements and kills bacteria extremely efficiently in laboratory tests.

Moreover, digitalization can achieve more economical and efficient dosages in wound care: Empa researchers are developing digital twins of the skin that allow control and prediction of the course of a therapy using real-time modeling.

Further information:
Prof. Dr. Katharina
Maniura Biointerfaces
Phone +41 58 765 74 47
Katharina.Maniura@empa.ch

Prof. Dr. René Rossi
Biomimetic Membranes and Textiles
Phone +41 58 765 77 65
Rene.rossi@empa.ch

The network for the development of fiber materials technology for healthcare and sports will receive funding from the Central Innovation Programme for SMEs (ZIM) for another two years.

The Federal Ministry for Economic Affairs and Climate Action (BMWi) approved a corresponding application in December 2021. This will continue to provide funding for the development of innovative functional fibers, smart textiles and application-optimized fiber composite materials until June 2023 and strengthen the technological competitiveness and innovative strength of small and medium-sized enterprises (SMEs).

For this purpose, the FIMATEC innovation network combines competences from different engineering and scientific disciplines with small and medium-sized manufacturers and service providers from the target sectors in medicine and sports (e.g. orthopaedics, prosthetics, surgery, smart textiles) as well as players from the textile and plastics industry.      

This interdisciplinary combination of industrial partners and application-oriented research institutions increases competitiveness and enables the players to realise their technical research and development projects quickly and in a targeted manner. The focus for the joint R&D projects of the companies and research institutions is on the development of innovative materials and efficient manufacturing technologies. 
          
Fiber-based materials have become indispensable in many applications in medicine and sports. As a pure fiber, processed into a textile or as a fiber composite plastic, they offer an almost unlimited variety for adjusting property and functional profiles. At the same time, the demands on the range of functions, performance and cost-effectiveness are constantly increasing, so that there is great potential for innovation. Developments are driven on the one hand by new materials and manufacturing processes, and on the other by innovative applications. Products with new and superior functions create a technological advantage over international competitors and enable higher sales revenues. In addition, efficient processes, application-optimized materials or even the integration of functions into the basic structure of textile materials lead to lower production costs and improved marketing opportunities in the future.
For developments in this context, the partners have joined forces in the FIMATEC innovation network, thus combining their expertise. Within the network, innovative materials and processes are being developed jointly in the following areas and tested in future-oriented products and services:

• Functional fibers
  Innovative fiber materials with integrated functionalities
• Preforming
  Highly load path optimized fiber orientations for complex fiber composite components.    
• Smart Textiles
  Textile-based sensors and actuators
• Hybrid material and manufacturing technologies
  Application-optimized components through cross-technology solution approaches.    
• Fiber composites  
  Intelligent matrix systems and function-optimized fiber materials.    
• Fiber-reinforced 3D printing  
  High-quality additive manufacturing processes for the efficient production of individualized products.

 
17 network partners are researching fiber-based materials for medical and sports technologyCurrently, ten companies and seven research institutions are involved in FIMATEC. Interested companies and research institutions as well as potential users can continue to participate in the cooperation network or R&D projects. In the course of membership, the partners are actively supported in identifying and initiating innovation projects as well as securing financing through funding acquisition. One application for ZIM project funding has already been approved by FIMATEC in its first year.

The aim of the already approved project "CFKadapt" is to develop a thermoformable fiber-plastic composite material for optimally adaptable orthopedic aids such as prostheses and orthoses. In the "Modul3Rad" project, which is currently being worked out in detail, the project partners intend to develop a modular lightweight frame system for the construction of user-friendly therapy tricycles, suitable for everyday use by severely and very severely disabled children. Three further collaborative projects are already in the planning stage.

The technology and knowledge transfer enables in particular small and medium-sized enterprises (SMEs) to access cutting-edge technological research, especially these are often denied access to innovations due to the lack of their own research departments. The IWS GmbH has taken over the network management for FIMATEC and supports the partners from the first idea to the search for suitable project partners and the preparation and coordination of funding applications. The aim is to obtain funding from the Central Innovation Programme for SMEs (ZIM), which offers companies funding opportunities for a wide range of technical innovation projects in cooperation with research institutions.

FIMATEC-netzwork partners
all ahead composites GmbH | Veitshöchheim | www.bike-ahead-composites.de
Altropol Kunststoff GmbH | Stockelsdorf | www.altropol.de
Diondo GmbH | Hattingen | www.diondo.com
Mailinger innovative fiber solutions GmbH | Sontra | www.mailinger.de
Sanitätshaus Manfred Klein GmbH & Co. KG | Stade | www.klein-sanitaetshaus.de
STREHL GmbH & Co KG | Bremervörde | www.rehastrehl.de
WESOM Textil GmbH | Olbersdorf | www.wesom-textil.de
Faserinstitut Bremen e.V. (FIBRE) | www.faserinstitut.de
E.F.M. GmbH | Olbersdorf | www.efm-gmbh.de
REHA-OT Lüneburg Melchior und Fittkau GmbH | Olbersdorf | www.rehaot.de
Fraunhofer-Institut für Fertigungstechnik und Angewandte Materialforschung IFAM | Bremen | www.ifam.fraunhofer.de
Leibniz-Institut für Polymerforschung Dresden e.V. (IPF) | www.ipfdd.de
Institut für Polymertechnologien Wismar e.V. (IPT) | www.ipt-wismar.de
Institut für Verbundwerkstoffe GmbH | Kaiserslautern | www.ivw.uni-kl.de

Associated network partners
9T Labs AG | Zürich, Schweiz | www.9tlabs.com
Fachhochschule Nordwestschweiz, Institut für Kunststofftechnik (FHNW) | www.fhnw.ch
KATZ - Kunststoff Ausbildungs- und Technologie-Zentrum | Aarau, Schweiz | www.katz.ch

For most people, the word "fashion" evokes thoughts of cuts, colors and patterns - but why not of live evaluations of vital functions or training sessions for rehabilitation patients? Up to now, products of the fashion industry have been largely analogous. The project Re-FREAM, however, was created to design smart clothes in the digital area. Here, researchers and artists work side by side, developing innovative and sustainable ideas and implementation options for the fashion industry, while simultaneously providing impulses for user-oriented synergies between textiles and technology.

The writer Maxim Gorki summed up the connection between two social spheres that were long believed to be irreconcilable: "Just as science is the intellect of the world, art is its soul". In the project Re-FREAM they are connected because fashion is not limited to the decision of the external, it is directly afflicted with sociological, technological and ecological world views. It is less and less sufficient to present only the beautiful, because the dark sides of the fashion industry must also be uncovered and countered with sustainable production cycles and fair working conditions. It is precisely this rethinking and redesigning of processes, production methods, but also of functionality and traditions in the world of fashion that is part of the Re-FREAM project.

The aim is to create an interaction between fashion, design, science and urban manufacturing in order to combine creative visions with sustainable technological solutions. In teams, artists and scientists developed projects together and then presented their innovative aesthetics at the virtual Ars Electronica Festival 2020.

The cooperation with Fraunhofer IZM's scientists opens up entirely new technological possibilities for artists: Microelectronics not only serves as a fashion accessory but is also brings new functions to clothing. With the help of integration technologies, clothing can be integrated into networks and textile-integrated sensor technology can be used, which opens up perspectives of wearable applications in the field of e-health.

One difficulty that Fraunhofer researchers are facing is the electronic contact points between electronics and textiles, because these must be manufacturable on an industrial scale and function reliably under typical textile mechanical stress and washing without any loss of performance. The electronic modules are a further challenge. At Fraunhofer IZM, the electronic components are miniaturized to such an extent that they do not stand out in the garment. The connecting conductor tracks are finally laminated or embroidered onto the fabrics.

Each sub-project in Re-FREAM is a unique joint effort, a fact that reflects the versatility of the cooperation partners. The Italian designer Giulia Tomasello, for example, wants to reveal taboos around female health in her project "Alma" and realize a monitoring of the vaginal flora. The team consisting of designers, an anthropologist and Fraunhofer researchers is developing underwear with an integrated pH sensor, designed to enable a non-invasive diagnosis of bacterial vaginosis and fungal diseases in everyday life and prevent serious inflammation.

In the gusset of the underwear, the reusable biosensor collects data and transmits them to a module measuring approximately 1 cm². Thanks to a modular design, the microcontroller can be easily removed from the textiles. The textile sensor, too, can be removed from the underwear. In addition to the technological solution, aesthetic requirements are another main focus. Other potential applications would be the monitoring of abnormal uterine bleeding as well as menopause. "Through close cooperation with the artists, we have gained very special insights into the user's perspective, and they in turn into that of application-oriented technologies. We have always challenged each other and have now found a solution that combines medical technology, wearables and a circular production method to empower women," says Max Marwede, who provided technical support for "Alma" at Fraunhofer IZM.

In the "Connextyle" project around designer and product developer Jessica Smarsch, the team also focuses on developing user-oriented garments: The tops, which are equipped with textile printed circuit boards and laminated EMG sensors, measure muscle activity and thus optimize rehabilitation processes for patients. An app provides visual feedback from the collected data, generates reports on the healing process and makes it easier for therapists to adapt the measures ideally.

Soft Robotics are the key point in the "Lovewear" project, because here inclusive underwear was developed, which is intended to help people with physical limitations in particular to explore their own intimacy and develop a greater awareness of their own body. Through interaction with a connected pillow, which functions as an interface, compressed air inserts are activated in the lace fabric. Instead of the commonly used silicon-based materials, Soft Robotics are made of textiles and thermoplastic materials. The researchers thus avoid the long curing process of silicone-based approaches and enable faster and more cost-effective mass production with available textile machines.

Particularly challenging and at the same time fruitful is the collaboration in creating sustainable and circular production designs in fashion. Ecological principles are taken into account at the design stage, minimizing negative environmental impacts throughout the product life cycle. This includes the reliability of the component contacts, the length of time the sensors adhere to the textile, the choice of materials and the modular design for reuse of the microcontrollers. However, the teams do not create individual pieces - they want to show that the path to high-tech fashion can also be an environmentally friendly one. They also worked on circular business models that fit the sustainable mission of the projects.

Thus Fraunhofer IZM’s expertise in the fields of e-textiles and circular design represents a considerable added value in the Re-FREAM project. With further investigations on suitable conductive materials, the researchers are currently developing sensory textiles and textile-suitable interconnection technologies. They are also working on thermoplastic substrates that can be integrated into almost any textile.

Re-FREAM is part of the STARTS (Science + Technology + Arts) program, which is funded as an initiative of the European Commission within the Horizon 2020 research and innovation program.

The trend towards the "Internet of Everything" is ongoing. Whether in industrial, medical or everyday applications, more and more electrical devices are connected to each other, record sensing values, exchange data and react to them. Due to smaller structures, new processing possibilities and new flexible materials, such systems are also being used more and more frequently in the textile sector. For example, medical measurements can be recorded directly on a garment, actuators such as EMS electrodes can be integrated directly into the textile or functions such as MP3 players, GPS receivers, fall detectors, heating structures and much more can be embedded simply and intuitively in textiles. Communication and data exchange usually take place wirelessly via WLAN, Bluetooth, RFID or, in the future, via the 5G network.

Electrical energy is required for such applications and functions. Despite the efforts to further minimize the energy demand of electronic circuits, it is not always possible to operate these systems completely energy autonomously. Therefore, energy storage devices such as batteries or rechargeable accumulators are necessary for operation. The big advantage of recharging is that smaller, more compact energy storage devices can be used to achieve the same or an increased service life running time. There are two basic concepts for recharging a battery with electrical energy. On the one hand wired and with connections like a micro-USB cable. On the other hand wireless via wireless power transmission. With wired solutions, contacts can wear out or be added by fuzz, especially in the textile sector. In addition, the connecting process is less flexible and uncomfortable.

Wireless concepts offer several advantages and are therefore better suited. For example, the electronics including energy storage can be completely encapsulated, since no galvanic contacts are required. Among other things, this makes the textile directly machine-washable, because the electronics are protected from water, detergents and sweat. This means that no components need to be removed from the textile when washing. A further purely practical advantage is the simplicity of charging. With the suitable concept, the textile can be hung on hangers, placed in laundry baskets or, ideally, simply placed in the washing machine and charged without any further action of the user. The result is an uncomplicated, charming way of operating smart textiles.

There are several concepts and possibilities for wirelessly supplying a textile with energy. The most popular and at the same time most efficient method is the inductive power transmission [1]. Two coils are inductively coupled to each other and thus transmit energy wirelessly (Figure 2). Air, wood, plastic, but also liquids such as water or human tissue can be penetrated a few centimeters almost loss-free.  There are also various concepts for integrating electronics into textiles. From the production of the entire circuit on thin printed circuit boards to complete textile integration, a wide variety of mixtures are possible. The easiest concepts to develop are those in which all circuit parts are manufactured on printed circuit boards. Thin printed circuit boards can have substrate thicknesses of a few tenths of a millimeter (Figure 1). But flexible possibilities such as manufacturing on silicones are also conceivable. Among other things, the sensors and microcontrollers as well as the coil for inductive energy transfer to the substrate are manufactured. This complete printed circuit board then only has to be connected to the textile, whether by gluing, sewing or insertion.

Concepts in which the receiver coil is integrated into the textile go one step further. For example, ultra-fine wires or strands are woven or embroidered and the textile material thus becomes the substrate itself as a functionalized textile. The rest of the circuit, which is still integrated on a conventional substrate, is then connected to the coil and the textile. Since some of the spools can have diameters of a few centimeters, one can gain in flexibility because the textile spool can move almost freely. With a complete textile integration, the components are finally attached to the textile and the conductor paths are embroidered or woven in.

Consistently implemented and used, wireless power transmission as a simple and convenient charging method of textiles can thus contribute to sustainably strengthen the market for smart textiles improving handling and user experience.

BAU 2017: Theme “interconnected buildings”: A Smart Home is a comfort zone. The lights come on automatically, the door unlocks as soon as an occupant approaches the building. Prior to this, the HVAG system has set the radiators to a comfortable temperature. The letterbox sends a text message when the mail arrives; the washing machine uses the cheapest electricity rates, if electricity has to be paid for at all, as the Smart Building is energy self-sufficient. It knows its occupants' habits and makes their lives as convenient as possible. Even Smart Cities can be created, just by linking these extremely smart buildings. Science Fiction? Not at all. BAU 2017 shows how far digital technology has as yet advanced.

In wintertime, when Julia König returns home after a long day at work, everything has been prepared: the apartment is nice and warm, the lights have been switched on in the hallway and the living room, and the blinds are already down. All relaxed she drops into her favourite armchair and looks forward to the evening ahead. When the young doctor leaves the house in the morning, the heating system automatically reduces the temperature, the security system is activated and all devices unnecessarily consuming electricity are being switched off.
There is no doubt: the smart home makes people's lives easier as it relies on intelligent building technology. What has been a "toy for techies" a few years ago has become reality today. Interconnectivity starts with simple sensors, switches and lights, and can lead to various living room scenarios – including the control of temperature, brightness, movement, door and window contacts, household appliances, communication technology, and entertainment electronics. In the case of a fire, smoke detectors save lives; motion sensors detect suspicious activity in the dark, whilst they have a deterrence effect; and alarm systems protect the house from burglars. From afar you can check whether the stove and the washing machine are off, and the gate is shut.

Smart Home Boom: New applications every week

Almost weekly, new applications are launched into the market. Smart homes thus become increasingly interesting for homeowners and tenants. Another reason is the level of comfort provided to the elderly.
Experts already call it a smart home boom. This is primarily due to one driver: the Smartphone. Since almost all users have an operating system in their pocket that can control more and more applications of the building technology in a very simple way. Apps are connected via Bluetooth Smartphone and Wi-Fi, or remotely via a mobile phone connection.
Hence, the market gets moving, as home automation system providers are finding new solutions in various communication protocols (radio and bus systems). They join up to facilitate more complex control options by combining individual solutions, and to further optimize the use of Smart Home applications.

Enhanced quality of life thanks to interconnectivity
Beyond merely managing heating, lighting and the home's security system these state of the art smart home applications offer far more. The latest developments even enable the connection of building components, such as glazing, doors, and windows; and turn them into intelligent systems that enhance the living comfort and energy efficiency of buildings.

One result could be, for instance, an intelligent facade. It converts smart homes into smart buildings. Smart energy management, shading control, security systems and monitoring functions, as well as real-time monitoring of all consumption and fabrication data of the building pave the way to intelli-gent and future oriented building construction. When this concept is rolled out from the individual building to an entire district, we get a Smart City.

One result could be, for instance, an intelligent facade. It converts smart homes into smart buildings. Smart energy management, shading control, security systems and monitoring functions, as well as real-time monitoring of all consumption and fabrication data of the building pave the way to intelligent and future oriented building construction. When this concept is rolled out from the individual building to an entire district, we get a Smart City.

Smart home solutions capture the market

The interconnected home faces a bright future. More and more smart home technologies are ready to be applied. Over the next few years they will have a major impact on our lives. At BAU 2017 in Munich, every two years the place to meet for everybody in the construction industry, you will be able to see the most significant novelties in this field.