In the journal Angewandte Chemie, a Chinese research team presented a straightforward new method of disinfection.
It is based on tiny biocompatible atom assemblies called quantum dots, which are formed of silver sulfide and have peptide caps that bind silver. They have synergistic effects when exposed to near-infrared light, which kills bacteria in water with great efficiency.
It can be exceedingly challenging to have access to safe drinking water, especially in developing countries and isolated areas of the world.
Serious infections can be brought on by pathogenic bacteria like E. coli, enterococci, salmonella, or cholera pathogens. Sometimes, one swallow can have catastrophic results.
Conventional disinfection techniques, which have been used extensively in recent years, such ozone, UV light, and chlorination, have drawbacks, including high costs, ineffectiveness, poor biocompatibility, and carcinogenic byproducts. Alternatives are required.
Xushen Qiu, Wei Wei, and Jing Zhao’s group has just unveiled a brand-new technique based on quantum dots constructed of silver sulfide (Ag2S).
Amounting to one to ten thousand atoms, quantum dots are nanoscopic objects that are “contained” in space. They have more molecular-like quantum mechanical characteristics than macroscopic materials, which can result in intriguing opto-electronic effects.
Existing photodynamic and photothermic therapies, such as those used to treat some cancers and skin conditions, use silver sulfide quantum dots.
They can be employed as fluorescence thermometers and contrast agents. They haven’t been utilized extensively for water disinfection thus far, in part because the preparation of them in the past has been difficult and expensive.
A quick, low-cost manufacturing process has been created by the researchers from Nanjing University and the Nanchuang (Jiangsu) Institute of Chemistry and Health, in which the quantum dots are encased in caps manufactured from a specifically created biomimetic silver-binding peptide (AgBP2).
The new AgBP2-Ag2S quantum dots efficiently eliminate germs in water when exposed to near-infrared (NIR) light. They are biocompatible, photostable, and chemically stable.
Their robust activity is the result of the interaction of two factors. They produce extremely reactive oxygen species as a result of irradiation, and they also strongly increase local heating.
Both of the effects work together to successfully damage bacterial cell membranes; neither one of them works by itself. During 25 minutes of NIR irradiation, they can eliminate over 99% of E. coli bacteria, making this method of antibacterial water disinfection very promising.
Source:Nanjing University
