While I was going through my social media channels, I came across a research article titled Antibacterial activity of silver-killed bacteria: the “zombies” effect. Because this was the first time I had ever seen a research article containing the word “zombies” in it, I was quite curious to read what the article was about.
The article, which was published in Scientific Reports, told the story of how silver could turn bacteria into zombies with the capacity to kill live bacteria. In the article, a batch of bacteria were killed off by exposing them to a silver nitrate solution. The dead bacteria were then separated from the solution and placed in an environment together with live bacteria. After 6 hours, 99.999 % of the live bacteria were dead. The explanation for this was that the original batch of bacteria that had been killed off with the silver nitrate solution had absorbed the silver and stored it as a silver reservoir. However, the silver began to leach out to the environment, which were absorbed by the live bacteria. As a consequence, these bacteria died as well. The researchers behind this study called this effect the “zombie effect”. As silver is relatively stable, the zombie effect could last several cycles of absorption and release. Meaning that it could kill several generations of bacteria.
Now some of you might wonder, so what? How is this important? This is actually quite important because it could give us an answer to the long-standing question: how can we prolong the effect of antibacterial agents? First off, using silver as an antibacterial agent is nothing new. It has been used for hundreds of years. However, the problem with antibacterial agents is that the effect is only temporary. They don’t prevent re-growth of bacteria, which can be a problem for people with serious wounds. Many researchers are trying to develop a sustained-release delivery system to allow the antibacterial agent to be continuously released over a period of time. Such system would lead to reduced doses of the antibacterial drugs being administered and thus prevent toxic effects that can arise due to high doses. The present study gives us hope that we might be able to achieve this in the future.