Comparative Bacteriology Analysis:
Particulate vs. Ionic Silver
December 22, 2004
Andrew Martin, B.S.
Claims have been made by the manufacturer of Mesosilver that suggest "ionic" silver potency is compromised by Hydrochloric Acid (HCl) in the stomach, and that only the particulate [species], elemental silver (i.e. the primary content in Mesosilver) will survive and therefore be effective in inhibiting microorganisms. Whether or not HCl in the stomach is an issue is well beyond the scope of this paper. Herein we are going to deal with only one issue: the antimicrobial effect of 'particulate' (elemental) vs. (free) 'ionic' silver.
The hypothesis of Natural-Immunogenics, Corp. is that, contrary to the claims above, it is the silver ion [species] that is primarily responsible for silver's antimicrobial efficacy. Natural-Immunogenics, Corp.'s products (Argentyn 23 and Sovereign Silver ) are composed in excess of 95% silver ions.
The purpose of this study, then, is to determine the antibacterial efficacy of both species, ionic vs particulate. This was to be achieved by comparing the two products, Argentyn 23 and Mesosilver, after the free ion content in both products was reduced or eliminated equally to the extent that only the particulate content in Mesosilver remained. This of course would reduce the ionic content of Argentyn 23 by the same amount.
This was accomplished by first exposing both products to the same amount of HCl. Identical bacterial concentrations and dilutions of two strains of Staphylococcus aureus (S-1 and S-2) were then used to test each product. This testing was accomplished by exposing healthy strains of the bacteria (in dilution series) to the two products after adding 10µl of HCl solution (in various concentrations).
Materials and Methods
The antibacterial activity of both Argentyn 23 and Mesosilver were compared by treating healthy cultures of the bacterial strains, separately, with each of the two products (to which was added 10µl of HCl solution, in various concentrations, to make 1 ml samples of each).
Source, cultivation, and preparation of bacterial samples:
Preparation of Test Media (YT):
Preparation of the silver products:
Treatment of Bacterial Strains with Silver Products
Qualitative results can easily be seen on each plate.
The negative control for S-1 grew out 4.5 spots, represented by (++++ ½ ), as did the negative control for S-2. These samples did not contain the silver or silver/ HCl mix. A (-) represents no Staph growth and (1/2) represents some Staph growth. The efficacy of the silver/HCl in the various ratios can be compared by the number of (+) vs. (-) spots observed.
The positive control (silver and NO HCl) for S-1 and S-2. This should have shown the greatest degree of kill/inhibition (since there was no HCl to degrade/inactivate the silver.
A + designation is given for complete or near-complete spot-growth. A ½ is given for mottled/speckled appearing growth. A ½ is given for only a few spots of growth. A - is given for NO growth. The right-most + or - character represents a 1/100,000 dilution of the stock bacterial suspension; the left-most + or - represents a 1/10 dilution. The more - characters from the right, the more potent the antibacterial activity. The negative control (representing NO silver/HCl treatment should show 4 + and one ½ characters, demonstrating the viability of the untreated bacterial employed.
The photographs of the results for the 4 minute exposure of the Silver/HCl (at 3 PPM) are shown below. The observations of the 4 PPM and 7 PPM and for both 4 and 8 minute exposures of Silver/HCl mixtures were virtually identical to those for the illustrated 3 PPM HCl (shown below).
The concentrations of HCl added to each of the two products were such that the concentrations of HCl in the final volumes would be 3ppm, 4ppm, and 7ppm. The range of concentration was determined in an earlier experiment. These concen-trations were selected because, if the HCl were to react with the silver, the conversion of Ag+ to AgCl would not make HCl the limiting reagent. The amount of remaining active silver would be the true limiting factor.
The following conclusions can be drawn from the data: