Methicillin-resistant Staphylococcus aureus (MRSA) and other drug-resistant bacteria could face annihilation as low-temperature plasma prototype devices have been developed to offer safe, quick, easy and unfailing bactericidal cocktails.
Two prototype devices have been developed: one for efficient disinfection of healthy skin (e.g. hands and feet) in hospitals and public spaces where bacteria can pose a lethal threat; and another to shoot bacteria-killing agents into infested chronic wounds and enable a quicker healing process.
Two papers published 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, often 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.
