Innovative Silver-Based Micromotors Promise Revolution in Water Purification
Dr. Pixy St. Claire reporting
Ian Harris, President and CEO of Outcrop Silver, will be participating in the upcoming Uranium, Battery and Precious Metals Investor Conference. This event is a fantastic opportunity for both individual and institutional investors, as well as advisors and analysts, to receive the latest updates on our high-grade Santa Ana primary silver project.
Presentation Details: Date: May 1st, 2024
Time: 10:30 AM Eastern Time
Don't miss the chance to hear directly from Outcrop Silver CEO and engage in real-time, interactive presentations.
Santa Ana - Future World’s Highest-Grade Primary Silver Producer
- end of that section
Innovative Silver-Based Micromotors Promise Revolution in Water Purification
Researchers at ICIQ in Tarragona have developed a simple technique to produce microscopic crystals that activate in the presence of light, releasing silver ions with antimicrobial activity.
Over 3,000 years ago, healers in ancient Greece used silver salts to prevent wounds from becoming infected. These salts continued to be used until Alexander Fleming discovered the first antibiotic "just" 100 years ago.
Antibiotics represented a major breakthrough in treating infectious diseases, but resistance soon emerged. Bacteria, which have been on the planet longer than us, have found ways to overcome different antibiotics, and today, antibiotic resistance is a major global health problem.
In a time when everything evolves very quickly, it is interesting to gain perspective and return a bit to the origins. That is why attention has turned back to silver salts, which were so widely used years ago and, in fact, never stopped being used.
Silver salts, due to their unique properties, serve as the foundation for the construction of microscopic crystals or micromotors. These crystals are developed by researchers from the Institute of Chemical Research of Catalonia (ICIQ-CERCA) in Tarragona in collaboration with the Catalan Institute of Nanoscience and Nanotechnology (ICN2).
These innovative crystals, aptly named micromotors, move autonomously in aqueous media under visible light irradiation. On their journey, they not only inactivate present bacteria but also hold immense promise for environmental recovery, hinting at a future where we can combat pollution and bacterial infections more effectively.
The group led by Dr. Katherine Villa at ICIQ, in collaboration with ICN2, has published a study in the journal Advanced Optical Materials that presents a simple technique for producing microscopic crystals that activate in the presence of light. Activation involves autonomous movement and the release of silver ions and free radicals with antimicrobial activity. Importantly, these crystals have a self-degrading property, which means they break down over time, leaving the water free of the crystals themselves.
Dr. Villa highlights the significance of the research, stating, "This work is important because we report a synergistic effect. This effect includes the self-propulsion capability of the micromotors under light stimuli, which allows for greater diffusion and dispersion of silver ions as well as released free radicals. This, in turn, enhances the antimicrobial activity of the crystals."
The researchers easily developed microscopic structures containing silver phosphate and shaped like tetrapods—crystalline structures formed by four arms, each about 5 micrometers long. These crystals, called TAMs, move autonomously through photocatalysis.
Photocatalysis, a process where light acts as a catalyst, is crucial in this research. In this case, light triggers a reaction between the silver phosphate of the TAMs and the water in the medium. This reaction releases oxygen, silver ions, and free radicals, which are responsible for the movement of the TAMs. Furthermore, the released radicals and silver ions are the agents that kill the bacteria in the medium.
The bactericidal action of the silver ions is a key aspect of this research. The effect of silver on the bacterial walls is such that it affects their permeability, causing irreparable damage to the cell wall and leading to the death of the bacteria. This understanding is crucial in exploring the potential applications of the research in antibacterial treatment.
The silver ions released from these micromotors become silver nanoparticles that can be quickly recovered by filtration, avoiding additional contamination. Dr. Villa explains, "The micromotors are twice as efficient compared to silver nanoparticles alone, according to the results obtained in the study. Additionally, if we prevent their movement, the antibacterial capacity of these micromotors is drastically reduced."
Micromotors, with their unique properties and capabilities, are an exciting tool for environmental recovery. Last year, Dr. Villa's team developed micromotors coated with laccase, a chemical compound that accelerates the conversion of urea into ammonia. This development opens up possibilities for using micromotors in the treatment of urea-contaminated water, contributing to environmental recovery. Additionally, the antimicrobial activity of the micromotors makes them a potential tool for antibacterial treatment.
Urea, a common product of residential activities and various industrial processes, is an emerging contaminant. In the context of environmental recovery, the conversion of urea into ammonia is significant. Ammonia is gaining importance as a green energy source; this compound can be decomposed for hydrogen production and stored as green fuel. Therefore, the development of micromotors coated with laccase, a chemical compound that accelerates this conversion process, is a significant step in environmental recovery.
In ancient Greece, over 3,000 years ago, healers used silver salts to prevent wounds from becoming infected.