Why do bacteria die on copper surfaces?

Researchers unravel a significant piece of the puzzle

It is a well-known fact that copper surfaces can stop the proliferation of dangerous germs. But it isn’t entirely clear why germs die when they come into contact with copper. Working with materials researchers from Saarland University, biochemists at the University of Bern have now unraveled an important aspect of this pheno­menon. Lab tests revealed that bacteria only die when they come into direct contact with copper surfaces. This discovery will help materials researchers develop coatings that could hinder the spread of bacteria, for example, for door handles and light switches in hospitals.

According to the Robert Koch Institute, nearly 500,000 people contract an infection in hospitals each year. Experts estimate that between 15,000-40,000 patients die yearly as a result. “That’s more people than die in traffic accidents,” compares Marc Solioz, professor of bio­chemistry at the University of Bern. The Swiss copper expert now plans to develop antibacterial coatings together with Frank Mücklich, pro­fessor of functional materials at Saarland University and director of the Steinbeis Research Center Material Engineering Center Saarland (MECS). Through their work, they hope to reduce the spread of dangerous in­fections in hospitals. “To create new materials like this, we must first understand how the copper actually kills the bacteria. This is because, while copper is known to have this deadly effect on bacteria, it is also the third most common dietary mineral in the human body – and it doesn’t seem to be as lethal to bacteria in that environment,” explains Solioz. At least five different explanatory models are currently being investigated by scientists around the world. But the fact remains, under an electron microscope, researchers can see evidence of copper ions inside the dead bacteria. It still isn’t clear how the copper gets into the interior of the cells, or what triggers the damaging process in bacteria.  Researchers in Saarbrücken used laser interference technology at the Steinbeis Research Center Material Engineering Center Saarland in their lab tests. A copper plate was coated with a thin layer of synthetic material. The materials researchers then used a laser to perforate this coating with tiny holes formed in a honeycomb pattern. The holes, only half a micrometer (or one millionth of a meter) in size, were smaller than the diameter of the bacteria. “The surprising result for us was that the bacteria didn’t die on this surface, although they were exposed to the copper ions,” explains Frank Mücklich. In contrast, a control test with an uncoated copper plate and the same concentration of copper ions showed that all of the bacteria died in just a few hours. “This in­dicates that the bacteria die primarily when exposed to direct contact with the copper surface. Apparently, in this process, the cell envelope is attacked first, creating the ideal conditions for the copper ions to completely destroy the cells,” concludes the interdisciplinary research team. It can thus be assumed that complex electrochemical processes play a role in the interaction between the copper plate and the bacteria on the surface. These processes now need to be researched in more detail in order to start developing actively antibacterial surfaces for materials

Swirled, not shaken!

Grüna-based company wins award for innovative technology developed with Steinbeis

Working with the company BMF in Grüna, the Steinbeis Innovation Center for Drive and Handling Technology in Chemnitz developed innovative technology for sandblasting, especially suited for small components. Together, they created a prototype. This novel in­vention – called “Twister” – had its debut presentation at Intec, the mechanical engineering trade show in Leipzig. It won the Intec Award in the category “Companies with up to 100 Employees”. 

The technical level, innovative power, and market potential together with the exceptional performance of the small company won over the jury, landing them an award endowed with €5,000. The innovative process developed by the two project partners allows for the treatment of the surface of small components – for inside surfaces as well as underneath. What makes the process so novel is that the work pieces are fastened in a central “satellite” holding fixture and moved in a type of “orbit” around the also rotating centrifugal wheel. The quick and easy exchange of multiple components allows for the simultaneous treatment of up to 40 pieces. Very little energy is expended, and the amount of sandblasting materials needed is minimal. The award for this category was sponsored by the Competence Center for Mechanical Engineering Chemnitz/Sachsen e. V., the RKW Sachsen GmbH, the Leipzig Department of Economic Promotion, and the Leipzig Trade Fair. The project was sponsored within the framework of the ZIM program of the Federal Ministry of Economics and Technology. 

The Intec trade fair is considered the top industry meeting point for the metal processing industry in Europe. Intec focuses on machine tools and special-purpose machines as well as on manufacturing technology.

Walking off the stress

Walk’n’Coach helps with the detection of burnout, plus prevention

Work, more work, even more work. Not enough time. Burning the candle at both ends. Constant availability. All things that place more and more strain on society, our bodies and our state of mind. The result: an increase in physical and psychological disorders, absenteeism, mistakes at work, unhappier people and less fulfilling lives. The Burnout and Stress Prevention Steinbeis Consulting Center has joined forces with companies and business experts, coaches, psychologists and medical practitioners to work on a new innovation project: Walk’n’Coach. 

Walk’n’Coach is part of a long-term health initiative aimed at companies. It works by incentivizing employees. To address root causes, staff members are taken on a 4-day coaching and hiking seminar and taught about the early signs of burnout as well as prevention. These topics are made tangible through the exchange of real experiences. The training covers all levels of stress prevention currently known to scientists.  

“Acquiring effective everyday strategies to counteract a broad variety of stress factors is ideal when it’s combined with moving around in the countryside. It’s there that your parasympathetic system is stimulated, and this enables you to have completely new experiences away from the office environment,” explains Vivien Brugger, director of the Consulting Center. 

Companies on the project benefit from a combination of teambuilding exercises and staff development processes, complete with tools of the trade that can be integrated into everyday situations. In the long term, this raises staff satisfaction and with this, enterprise value.


Vivien Brugger
Steinbeis Consulting Center for Burnout and Stress Prevention (Friedrichshafen)

Manufacturing-based planning of castings

Practical training in the foundry lab at Aalen University

In March of this year, the GTA Steinbeis Transfer Center (Technology Foundry Aalen) organized the first two-day practical training course in the Aalen University foundry lab. The course – Manufacturing-Based Planning Of Gray And Nodular Cast Iron Parts – was targeted at product design specialists, production planners and purchasing managers involved in the construction and supply of cast iron parts used in machines and mechanical engineering.

Prof. Dr.-Ing. Lothar Kallien, director of the GTA, started with a theory session on the different properties of cast iron with flake graphite and nodular cast iron, including production methods. Dr.-Ing. Alexander Baesgen then discussed the individual steps of manual and mechanical cast production. During the practical session, course participants made casting molds out of bentonite and cold-setting molding sand, complete with corresponding castings. Finally, the cast iron was smelted with spheroidal graphite and cast iron alloys in varying degrees of con­centration in the laboratory’s 100 kg induction furnace and poured off.  

On the second day, the course examined the key principles of casting-related component design. In the theory session, Dominik Krieger, CEO of the Aalen-based model manufacturer Krieger Modellbau, showed how clever component design can result in major savings even before parts are cast, not just in production but also during later processing of castings. During the practical session, the castings produced the previous day were evaluated by making metallographic microsections and then subjected to statistical tensile testing. The course finished with a discussion on casting flaws like blowholes, undesirable areas of hardness on the test parts, and corrective actions. The premiere proved such a success that further courses have already been scheduled.

World-class award winners

Bestowal of the Baden-Wuerttemberg Competence Prize

The “Control” trade show in Stuttgart got off to a traditional start with the sixth bestowal of the Baden-Wuerttemberg Competence Prize for innovation and quality. The initiators, the TQU Group and P.E Schall, award the prize to companies that overcome the sometimes conflicting issues of innovation and quality, but that success­fully translate these principles into business and thus achieve excellence. The 2013 prize went to the Westerheim-based metal bandsaw manufacturer MEBA, with a business personality prize going to Dr.-Ing. E. h. Martin Herrenknecht, chairman of Herrenknecht. The Research Center for Informatics Karlsruhe (FZI) was awarded an honorary prize. Steinbeis is the patron of the award, which is bestowed in cooperation with the Südwestmetall employers’ federation, the Baden-Wuerttemberg State Association of Industry (LVI) and the German Chemical Industry Association (VCI).

As CEO of TQU Business Helmut Bayers confirms, the competence prize has developed into more than an integral feature of the business environment in Baden-Wuerttemberg over the years. A great importance is attached to the award, a fact that is underscored by the number of entrants and the variety of participants: “We’re contacted by research institutes, machine makers, equipment manufacturers, pharmaceutical, software and electrical engineering companies, even the construction industry.” The quality and innovative flair of the companies in Baden-Wuerttemberg is reflected by the award winner, MEBA Metall-Bandsägemaschinen GmbH. Its semi-auto­matic and fully automatic saw solutions for vehicle construction, metal manufacture, steelmaking and heavy industry have made the metal bandsaw maker the number one worldwide. The company’s modern machinery includes the MEBAe-cut, the world’s first completely hydraulic-free, high-performance sawing machine. The competence prize jury was won over by the innovation, sustainability and performance of the company’s products. CEO of MEBA, Mark Diener, was delighted with the award: “We’re a family-run business and place a great deal of emphasis on organic growth through systematic processes, quality in all areas, and the development of new, groundbreaking products. We consider these three pillars to be the key to the future survival of MEBA,” emphasized Mark Diener, with special thanks going to his co-workers.   For many years, experts worldwide have considered Dr.-Ing. E. h. Martin Herrenknecht and his company an entrepreneur of the utmost professionalism. The jury awarded Herrenknecht the competence prize for his “entrepreneurial vision,” for treading “unconventional paths,” and for his “amazing, courageous work and impact in commercial and social areas.” Presenting the award, Professor Dr. Heinz Trasch summarized it succinctly: “He may have done things the unconventional way in his successful career, but he always proved to possess entrepreneurial farsightedness, and he led his company to number one position worldwide. He’s created a jewel in Baden-Wuerttemberg and thus has not just impressed the jury, but lots of other people as well with his unerringly courageous commitment in commercial and social areas.” Martin Herrenknecht thanked the initiator, quoting Robert Bosch: “It’s better to forfeit money on a project than trust.” Trust is the foundation of quality and innovation, which in turn are a prerequisite of engineering and export.  A special honor was awarded to the Research Center for Informatics Karlsruhe (FZI), which enables information transfer at the interface between university research and practical business application. The FZI applied for the Competence Prize 2013 for a new kind of research environment, the House of Living Labs (HoLL). The HoLL impressed the jury as an approach toward a new kind of research for science and business, as a user-based training location for young scientists, and for providing interdisciplinary collaboration options to different partners.


Ellen Spieth
TQU Business (Ulm)

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