Polski
The water supplied to our homes should be safe for us, meaning free of viruses and bacteria. In Poland, the Minister of Health sets the requirements that water intended for consumption must meet by decree. Thus, we can use the resources without hindrance or health risks.
And what is it like in the world? More than 800 million people cannot enjoy safe drinking water on a daily basis, and the water that is available to them can cause disease and death. Or rather, not her, but the bacteria and viruses in the water. They are a very serious problem faced by many communities, especially those living in poverty. Escherichia coli, enterococci, salmonella, cholera pathogens and many others are a daily threat to them, so combating the lack of clean drinking water is extremely important.
Bacteria in water – a simple and effective method of disinfection
In March this year. The German journal Angewandte Chemiepublished an article describing a new, simple method for disinfecting water. Chinese researchers led by Xushen Qiu, Wei Wei and Jing Zhao worked on the study. Their method is based on tiny, biocompatible assemblies of atoms, known as quantum dots. These are nanoscopic structures consisting of one to ten thousand atoms that are “confined” in space. They have quantum-mechanical properties that match those of molecules and produce interesting optoelectronic effects.
What is the process based on?
Made from silver sulfide, the quantum dots are surrounded by silver-binding peptides made from a specially formulated biomimetic. Irradiated with near-infrared light, they effectively kill bacteria in the water. This is because after irradiation, they produce highly reactive oxygen species and strong local heating of water. Separately, neither of these two effects leads to success, but their synergistic combination destroys bacterial cell membranes. According to the researchers, this is a very effective, simple and inexpensive way to disinfect water. The bacteria in the water are destroyed almost completely. The method is capable of killing 99.06% of Escherichia coli within 25 minutes of exposure.
