Researchers Again Prove Silver Ions Kill Pathogens, Not Metallic Silver

Hi, Steve Barwick here, for The Silver Edge

I continue to see people posting articles on the internet claiming that the metallic form of colloidal silver is the only effective antimicrobial form, and that the ionic form of colloidal silver is not effective at all against pathogens.

Of course, I've debunked that oft-repeated notion numerous times over the past 20 years, and have demonstrated that the truth is quite the opposite of these erroneous assertions.

I even published an entire web page replete with tons of clinical documentation and quotes from bona-fide clinical research experts to demonstrate just how false the notion is. You can read that web page here: True Colloidal Silver Facts

Another New Study Proves
Ionic Silver (But Not Metallic) Silver Kills Pathogens

Now, brand new research has confirmed the older research I've previously reported on – and it's done so in quite an unusual way.

In a clinical study titled "The Antimicrobial Properties of Silver Nanoparticles in Bacillus subtilis are Mediated by Released Ag+ Ions," clinical researchers from two different medical universities in Taiwan did something quite different from what's been done in other studies.

First, they exposed pathogens to metallic silver nanoparticles – i.e., very small submicroscopic particles of metallic silver – and waited until the pathogens died.

That's where most researchers generally stop and conclude that particles of metallic nanosilver kill pathogens.

But this intrepid group of researchers decided to take the time to examine the silver inside of the pathogens and determine what kind of silver it was.

Their hope was to determine whether the metallic nanosilver itself was the antimicrobial agent, or whether the metallic nanosilver was merely shedding silver ions in order to kill the pathogens.

What the researchers discovered was that there was no metallic nanosilver whatsoever inside of the pathogens.

Indeed, the chemical "signature" of raw metallic silver – i.e., Ag0 – could not be found. Instead, the silver that penetrated and killed the pathogens was composed of silver ions – i.e., Ag+ – which through the process of oxidation had been converted inside the bacteria to Ag20 (silver oxide) after they died.

In other words, the researchers proved what I've said all along: Metallic nanosilver is basically inert. It cannot kill infectious microbes except to the extent that it sheds silver ions in the presence of the microbes, and the silver ions then penetrate the bacterial cell wall and kill the microbe.

Here's What the Researchers Wrote

Here, in brief, is what the researchers wrote after completing their study (I'll explain their findings briefly, afterwards):

"There is an ongoing debate over whether silver nanoparticles inherently possess toxicity, or if microbial toxicity is dependent on leached Ag+ ions [i.e, silver ions – ED] from nanoparticles.

To clarify this issue, we utilized XANES/EXAFS analysis to assess the fine structure of silver particles present within Bacillus subtilis cells treated with 100 ppm of silver nanoparticles.

This data strongly suggests that in aqueous solutions, silver nanoparticles leach off positively charged silver ions, which subsequently enter bacterial cells and are oxidized to form Ag2O [silver oxide – ED].

If silver nanoparticles entered cells directly, it would have been possible to detect spectra corresponding to the Ag standard.

… this is the first study to directly analyze silver particles present within bacterial cells treated with silver nanoparticles, and the results indicate that positively charged silver ions are primarily responsible for silver nanoparticle microbial toxicity.

… our results support the theory that silver nanoparticles exert microbial toxicity through the release of positively charged silver ions that subsequently penetrate into bacterial cells."

– The Antimicrobial Properties of Silver Nanoparticles in Bacillus subtilis are Mediated by Released Ag+ Ions, PLOS-One, December 15, 2015

This is quite fascinating, of course, because the so-called "true colloidal silver" crowd is always claiming that silver ions become neutralized in the body and therefore cannot kill pathogens, and that only metallic nanosilver (aka silver nanoparticles) can penetrate the shell wall of the microbes and kill them.

But this new study (along with many older studies I document on the aforementioned True Colloidal Silver Facts web page) demonstrates conclusively that metallic silver nanoparticles don't penetrate infectious microbes and kill them, but silver ions being shed by the metallic silver nanoparticles do.

Proper Examination Proves the Point

What makes this new study stand out head-and-shoulders above the others is that the researchers actually took the time to examine the silver inside of the dead microbes, and determine what actually killed them.

They used a special form of x-ray analysis called "XANES/EXAFS analysis" to determine what kind of silver would be found inside the dead microbes.

And what they found were silver ions that had penetrated the bacterial shells, killed the bacteria, and then were oxidized, i.e., turning the ionic silver into silver oxide similar to the gray coating you'll find on the positive silver rod of a colloidal silver generator after making a batch of ionic colloidal silver.

Indeed, the researchers essentially concluded that the metallic nanosilver serves as nothing more than a carrier or reservoir of silver ions. But it cannot kill the pathogen without shedding those ions. The silver ions are the real assassins. The metallic nanosilver is merely the vehicle through which the silver ions are delivered to the microbe.

All of which leads me to point out once again that the ionic form of colloidal silver is superior to the metallic nanosilver form, because it doesn't have to be converted from metallic silver to ionic silver inside the human body in order to be effective.

This demonstrates once more that the silver ion (i.e., ionic silver) is the active, infection-fighting form of silver, and that metallic nanosilver can only work against pathogens to the extent it sheds silver ions.

More importantly, it demonstrates that when researchers claim they've proven in clinical studies that nanosilver kills pathogens, they've never checked to see if the "specie" of silver inside the pathogens is the metallic nanosilver they used in the study, or the silver ions being shed by the nanosilver in the presence of the pathogens.

Instead, they simply assumed it was the metallic nanosilver doing the killing. And of course, as the old saying goes, whenever one "assumes" something, the end result often makes an "ass" out of "u" and "me."

The Rice University Study

In a previous clinical study which I reported on several years ago, researchers from Rice University produced similar results:

Quoting directly from the Abstract of the Rice University study, titled "Negligible Particle-Specific Antibacterial Activity of Silver Nanoparticles", which was published in the July 5, 2012 issue of the journal Nano Letters:

"For nearly a decade, researchers have debated the mechanisms by which silver nanoparticles exert toxicity to bacteria and other organisms. The most elusive question has been whether the silver nanoparticles exert direct "particle-specific" effects beyond the known antimicrobial activity of released silver ions (Ag+).

Here, we infer that silver ions are the definitive molecular toxicant. We rule out direct particle-specific biological effects by showing the lack of toxicity of silver nanoparticles when synthesized and tested under strictly anaerobic conditions that preclude Ag(0) oxidation and Ag+ release."

In other words, when the researchers took away the ability of the metallic nanosilver to shed silver ions, the metal particles were no longer toxic to bacteria. It is only when metallic silver (i.e., nanosilver) is able to shed silver ions that it can kill bacteria.

So the big question is this: Why bother to use metallic nanosilver at all, when instead you can simply use the active infection-fighting form of colloidal silver – ionic silver – and kill the pathogens faster and more reliably?


Steve Barwick
Steve Barwick

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