Plasma produces KO cocktail for MRSA

hands and feet) in hospitals and public spaces where bacteria can pose replica watches uk a lethal threat; and another to shoot bacteria killing agents into infested chronic wounds and enable a quicker healing process.

Two papers published today, Thursday 26 November, as part of a selection of papers on Plasma Medicine in New Journal of Physics (co owned by the Institute of Physics and German Physical Society), demonstrate how far the design of equipment to harness the bacteria killing power of low temperature plasma has come.

Plasma, oft called the fourth state of matter after solid, liquid and gas, is defined by its ionized state. In space, stars are made up of high energy plasma and, on Earth, it is researchers in high energy plasma that are making significant strides towards limitless energy from nuclear fusion. The high energy of plasma stems from some atoms or molecules in a gas being stripped of their electrons, resulting in a mix of ionized and neutral species.

Also on Earth, scientists have been working on low temperature and atmospheric pressure plasma and have found applications in a range of industries, from plastic bag production to the manufacturing of streetlamps and semiconductor circuits.

In a low temperature plasma, unlike its high temperature counterparts, the temperature of ions and neutral particles stays low. The ‘recipe’ for producing such plasmas is simple: the fraction of atoms (molecules) that are ionized and therefore are hot is so low that collisions with cold neutral atoms (molecules) quickly reduce their temperature again. The analogy of adding a drop of hot water to a bucket of cold water gives a sense of how low temperature plasma physicists are able to create plasmas without dramatically increasing the temperature of the overall molecules.

In medicine, low temperature plasma is already used for the sterilization of surgical instruments as plasma works at the atomic level and is able to reach all surfaces, even the interior of hollow needle ends. Its ability to disinfect is due to the generation of biologically active bactericidal agents, such as free radicals and UV light, which can be delivered to specific locations. It is research into how and why these biologically active agents are generated that has led to the construction of medically invaluable devices.

One research group from the Max Planck Institute for Extraterrestrial Physics has built and trialed a device which is capable of disinfecting human skin safely and quickly (within seconds), annihilating drug resistant kinds of bacteria that currently cause approximately 37 000 deaths from hospital induced infections every year in EU countries.

On the current disinfection challenge that medical staff face, and that their device will overcome, the researchers write, “The surgeons’ disinfection procedure hand rubbing (3 minutes) or hand scrubbing (5 minutes) has to be repeated many times a day, with a number of negative side effects arising from the mechanical irritation, chemical and, possibly, allergic stress for the skin. For the hospital staff, the issue of hand disinfection is equally daunting. a total of 3 to 5 hours!”

The new plasma devices under development cut this down dramatically to around ten minutes a day. In addition, only electricity is needed, no fluids or containers.

Another device, an ‘argon plasma torch’, was developed by this group, together with ADTEC Plasma Technology Ltd in Japan, specifically for disinfecting chronic non healing wounds. One advantage of the ‘argon plasma torch’ comes from regulating densities of biologically active agents which are designed to ensure that the plasma is deadly for bacteria but harmless for human cells.

Cell biological studies, conducted together with partners from the Institute of Pathology, Technical University of Munich, are reported and interpr replica watches uk eted in terms of chemical reactions which work differently in bacterial and human cells deadly to the bacteria and supporting cell regeneration in human cells.

After successful trials that show how plasma can be manipulated to very beneficial end replica watches uk s, these researchers write, “One can treat plas replica watches uk mas like a medical cocktail, which contains new and established agents that can be applied at the molecular level to cells in prescribed intensities and overall doses.”

This work represents a first step in the direction of ‘plasma pharmacology’, a step along a path that will require considerable research efforts to harness the full potential of this new field of ‘plasma medicine’.

Both research papers describe the mechanics of their trials, the safety concerns they endeavour to overcome, the remarkable bactericidal effect they have successfully achieved, and the positive cell regeneration effects that can be stimulated using plasmas.

Plasma in bags

Physicians are increasingly using live cells in their treatments: in blood transfusions and bone marrow transplants, as well as in stem cell therapies and following severe burns. Cells taken from the patients themselves are ideal for replacing burned skin, eliminating immune deficiencies, repairing degenerated cartilage or to treat injured bones as they are not rejected by the immune system. These cells have to be kept, cultivated, reproduced or even modified in a patient specific manner. The problem, however, lies in the storability of the cell solutions used. As they can easily become infected by germs, they can only be stored for a few days in the containers conventionally used today. The joint project InnoSurf aims to remedy this problem: scientists from five research institutions, along with partners in the industry have developed innovative plastic surfaces and measuring methods for efficiently producing human cells for diagnostic and therapeutic applications. The work was coordinated by the Helmholz Centre for Infection Research (HZI) in Braunschweig, Germany.

The idea is to cultivate the cells in sealed, sterile plastic bags. The inner surface of the bags has to be modified so that they provide cells with good conditions replica watches uk for survival. A team led by Dr. Michael Thomas at the Fraunhofer Institute for Surface Engineering and Thin Films IST in Braunschweig, Germany, has now developed a plasma technology process for use at atmospheric pressure. “We fill the bags with a specific gas mixture and apply an electrical voltage” explains scientific assistant Dr. Kristina Lachmann. a luminescent, ionized gas, which chemically alt replica watches uk ers the plastic surface”. During this process the bag remains sterile as plasmas also have a disinfecting action. “The advantage of the process is that it operates at atmospheric pressure and is therefore cost effective, fast and flexible” emphasizes group leader Dr. Michael Thomas who specializes in the use of such atmospheric pressure plasmas to modify surfaces.

The new bags facilitate the sterile handling of cell cultures. Previously, researchers and clinicians had to use open Petri dishes, bottles or bioreactors replica watches uk . As these systems need to be opened, at least for filling, contamination can easily occur. By contrast, when using the new technology with its sealed bag system, the cells migrate directly into the bag via an injection needle or connected tube systems without coming into contact with their surroundings. The sterile interior of the bags contains nutrient medium and germ free air or a suitable gas, which been added beforehand. Even during the cultivation period the containers do not have to be opened, and at the end the cells can be removed again by injection needle.

The researchers also maybe intend to use the disposable systems for growing artificial organs. If the bags are provided with a three dimensional structure, cells could attach themselves to it and create artificial skin, nerves, cartilage or bone which could be used prosthetically in the patient. So far their cultivation has mainly failed because the stem cells have been reluctant to attach themselves to spati replica watches uk al structures. The plasma process developed at the IST could solve this problem. In collaboration with the University of Tbingen, Braunschweig City Hospital plans to isolate certain stem cells from tissue samples and investigate on which of the new plastic surfaces they could develop into bone or cartilage, for example. For this development by the group led by Dr. Michael Thomas, the IST was awarded “Selected Location 2011″ as part of the “Land of Ideas” initiative. The prize will be awarded at the IST in Braunschweig on December 8, 2011.

Plasma in a bag

It sounds like one of those puzzles where you have to change a matchstick figure into something else without adding or taking away any matches: How do you alter the inside of a closed bag without opening it? Impossible, I hear you say. But that is precisely what a team of researchers under Dr. Kristina Lachmann and Dr. Michael Thomas at the Fraunhofer Institute for Surface Engineering and Thin Films IST in Braunschweig have managed to do. They use plasma to activate the inner surfaces of plastic bags. The plasma acts as a disinfectant while also transforming the surface of the bag so that cells want and are able to grow on it.

“Our goal was to realize a closed system in which cells grow undisturbed and without the risk of contamination,” says Dr. Henk Garritsen from Braunschweig Municipal Hospital (Stdtisches Klinikum Braunschweig). “Coating the bags with plasma enables us to use them as a GMP laboratory.” The background to these endeavors is stem cell research and the idea of treating illnesses with stem cells that come from the patient’s own body. Until now researchers have mostly used Petri dishes, bottles, and bioreactors in a sterile environment for cultivating stem cells. Howe replica watches uk ver, these systems have to be opened in order to refill culture media or extract cells. replica watches uk This leads time and again to contamination, and the painstakingly cultivated cells become unusable.

At the Helmholtz Centre for Infection Research in Braunschweig, Dr. Werner Lindenmaier and Dr. Kurt Dittmar were already working on bags for cultivating stem cells, but without making the breakthrough they were looking for. The geographical proximity and the expertise of Fraunhofer IST researchers in plasma coating brought the two teams together. Initial tests showed that the cells grow on plasma coat replica watches uk ed films. A joint project sponsored by the German Federal Ministry of Economics and Technology BMWi set out to investigate the closed bag system and cell growth in greater detail.

The key part of the method is coating with plasma. To achieve this, ordinary bags such as those used for infusions are filled with a noble gas and voltage is applied. “This produces plasma inside the bag for a short period a luminous, ionized gas that chemically alters and at the same time disinfects the surface of the plastic,” explains Dr. Kristina Lachmann from Fraunhofer IST. Bags were coated in a pilot plant at Fraunhofer IST, and then tests were carried out at the Helmholtz Centre for Infection replica watches uk Research and Braunschweig Municipal Hospital to determine which coating is best suited for which type of cell. “We work with stem cells for bones, cartilage, fat, and nerves the coating can be optimized for each of these cell types,” says Dr. Kurt Dittmar.

The pilot plant at Fraunhofer IST has now been optimized to the extent that the individual coating steps are automated. This makes it possible to manufacture standardized and reproducibly modified bags for cell cultivation. “We use medically approved bags for the coating,” says Dr. Michael Thomas. “Nevertheless, the plasma treatment must be demonstrated to be innocuous before being approved for clinical use.”