Colloidal Gold and Silver FAQs

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What exactly is colloidal gold?
Mesogold® is a clear reddish colored liquid that looks like light colored cranberry juice. It is the very high concentration ogold particles that gives Mesogold its distinctive coloration. Mesogold consists of 99.99% pure gold mesoparticles suspended in pure deionized water. The actual size of the gold mesoparticles has been measured to have a mean diameter of .65 nm and is estimated to contain about 9 gold atoms. This is uncommonly small compared with the size of particles found in other commercially available colloidal gold products.The small size of the gold particles is confirmed by the use of a state-of-the-art scientific instrument designed specifically for measuring such small particles called a Photon Correlation Spectrometer (PCS). The PCS used during the development of Mesosilver® was manufactured by Malvern Instruments, Ltd. of the United Kingdom, one of the foremost producers of such equipment in the world. The particle size report from the Malvern PCS confirms the claimed size of 65 nm for Mesogold. The gold content of Mesogold is 100% contained in the particles. There are no gold ions in Mesogold.

What exactly is colloidal silver?
Mesosilver® is a clear brown colored liquid that looks like dark iced tea. It is the very high concentration of Mesosilver particles that gives Mesosilver its distinctive coloration. Previously, it was thought that such a brown color indicated the presence of large silver particles, which is the case for colloidal silver produced by methods other than the mesoprocess. The small size of the silver particles is confirmed by the use of a state-of-the-art scientific instrument designed specifically for measuring such small particles called a Photon Correlation Spectrometer (PCS). The PCS used during the development of Mesosilver was manufactured by Malvern Instruments, Ltd. of the United Kingdom, one of the foremost producers of such equipment in the world. The particle size report from the Malvern PCS confirms the claimed size of .65 nm for Mesosilver. The total content is expressed as milligrams of silver per liter (mg/L) of water which is numerically the same as parts per million (ppm) The total silver content is divided into two forms of silver, ionic silver and silver particles.

What is Ionic Gold?
Find out about Ionic Gold.

What is Ionic Silver?
Find out about Ionic Silver.

What is the comparison cost with Ionic Silver?
Find out about the comparison cost with Ionic Silver.

How is "total silver" concentration determined?
The total amount of silver that is reported as the silver concentration (in parts per million) is the sum total of the silver contained in the particles and the silver contained in the silver ions. Accurate measurement of total silver content requires the measurement by either atomic absorption or atomic emission of the silver atoms. An Atomic Absorption Spectrophotometer (AAS) is typically used for accurate results.

What does "particle surface area" mean?
Particle surface area is the total surface area in square centimeters (cm2) of all the particles in one milli-liter(mL) of colloid. The surface area is a calculated value based on the concentration of particles (ppm) and the mean diameter of the particles. The calculation assumes the particles are spherical. Particle surface area is inversely proportional to particle size, which means for a constant concentration of particles, the surface area increases as the particle size decreases. In the chemical world, reactivity increases with increasing surface area. Therefore, the effectiveness of colloidal solutions increases with decreasing particle size as the particle surface area increases. For this reason, particle surface area serves as a metric for comparing different colloidal solutions. In metal colloids the increase in reactivity that derives from the increased particle surface area translates directly to effectiveness of the colloid. Surface area is expressed in square centimeters (cm2) per milli-liter (mL) of colloidal solution, and is written as (cm2/mL). For example, the particle surface area of 1 ppm of particles having a mean diameter of 10 nm is 0.423 cm2/mL, while 1 ppm of 1 nm diameter particles has a particle surface area of 4.229 cm2/mL, which is ten times the surface area of the 10 nm particles.

Why is "particle surface area" important?
Particle surface area is what determines a colloid's ability to react with its environment. Reactivity increases with increasing surface area. Particle surface area can be determined by measuring the physical properties of a colloid. Because it is comprised of two important physical properties, namely, particle size and particle concentration, it serves as good metric for comparing colloids. Since it can be expressed as a single number, particle surface area can be considered a figure of merit for the effectiveness of a colloid. In this context, effectiveness is defined as the ability of the colloid to react with its environment. The higher the surface area, the more reactive the colloid, hence the more effective it is in reacting with its environment.

Why do the silver colloidal particles stay suspended and not fall to bottom?
The nanometer size particles of silver posses an electric charge that results in mutual repulsion of the particles and causes them to be dispersed throughout the suspension. This charge is called zeta potential and is negative.

Are the silver particles made of single atoms of silver?
A single silver atom can be considered to be an atomic sized particle of metallic silver. It is the smallest size of silver matter that exists. The diameter of a single silver atom is 0.288 nm. While it is theoretically possible to have a particle of metallic silver that consists of a single atom, in practice particles are much larger and consist of many atoms. Just for reference, a particle one nanometer in diameter would consist of 31 silver atoms, and a 5 nm diameter particle would be about 3900 atoms while a 20 nm diameter particle would contain about 250,000 silver atoms.

Single atoms of metallic silver are drawn to other silver atoms by 'force" van der Waals' force of attraction causing the atoms to form particles made up of many atoms. Because single atoms do not possess a repulsive force, there is nothing to prevent the force of attraction from creating ever larger particles from any available atoms in solution. Larger particles develop an electric double layer of ions surrounding the particle, which causes a charge to form called zeta potential. The zeta potential charge of particles in low ionic solutions is negative. The zeta potential creates a repulsive force that causes the particles to to be repelled from each other and uniformly dispersed in the solution. As long as the magnitude of the zeta potential is sufficient to produce a repulsive force that can overcome the force of attraction, the particles remain in suspension.

Why is it important to know how much of the total is ionic?
The benefits of colloidal silver in the human body are produced by the nanometer sized metallic silver particles not the ions. In most colloidal silver products a large quantity of ionic silver is produced as a by-product of generating the silver particles. The prominent methods of production are electrochemical processes using either low voltage DC current or high voltage AC. Both the AC and DC process may employ a constant voltage or a constant current source. Both the DC and the high voltage AC produce a significant percentage of the total silver as ionic. Typically, 75 - 99% of total silver is ionic depending on process variables. In some products claiming very high concentration levels, almost the entire silver content is ionic. To state the silver concentration in ppm without specifying what percentage is ionic is misleading to say the least. Therefore, it is important to know what percentage of the silver concentration is ionic to properly evaluate the quality and effectiveness of the product.

Is there a simple way to demonstrate the ionic silver present?
To demonstrate ionic silver content, all that is needed, is a chloride ion source to be added to a small amount of colloidal silver. Normal table salt is sodium chloride (NaCl). When table salt is dissolved in water it decomposes into sodium ions and chloride ions. To demonstrate: Place a small amount (1-2 ounces) of colloidal silver in a clear glass. Add a few grains of table salt. Observe that as the salt dissolves a white cloud of silver chloride forms in the solution. Eventually, the entire solution will turn cloudy. If more salt is added, the white silver chloride will become denser until all the silver ions have combined with the available chlorine ions. If no silver ions are present then no white cloud will form.

Would a silver colloid with a high particle surface area be better at killing pathogens?
Theory would lead us to believe that maximizing the surface area of metallic silver in contact with pathogens would increase the colloids ability to kill such pathogens. Silver colloids are available with widely varying amounts of particle surface area. Because this is considered an important metric for comparison, the particle surface area comparison is reported in the Table section of this site. Generally, products that contain a high percentage of silver in the form of silver ions will have a very low particle surface area, while products that have a high percentage of silver in the form of particles will have a higher particle surface area. The highest particle surface area will be found in products having the highest particle concentration and the smallest sized particles.

How is "ionic silver" concentration determined?
To measure the concentration of silver ions by atomic absorption requires that the particles first be removed by centrifugation leaving only the ions. Alternatively, an Ion Selective Electrode (ISE) can be selected that only responds to the silver ions in solution. ISE measurements are less accurate than AAS and are generally accurate to within about 2%.

How is the concentration of silver particles determined?
The concentration of silver particles is determined by subtracting the ionic concentration from the total silver concentration.

What percent of the silver concentration is ionic silver?
That varies greatly depending on the manufacturer and the process used to produce the product. Many products are predominantly ionic silver (75 - 99%).

What is the highest concentration of ionic silver that pure water will keep in solution?
If no other contamination anions are present, the maximum concentration of silver ions that pure water can hold at room temperature in an unsaturated solution is 13.3 ppm. In practice, there is substantial dissolved CO2 in the water, which provides additional anions, so a higher concentration of silver ions is possible without saturation.

Can ions clump together to form metallic silver particles?
In an unsaturated solution, ions are dispersed throughout the solvent by repulsive force and exist as separate entities. However, in a saturated solution, ions will precipitate out as large flakes of metallic silver particles as the solution cools. These flakes are usually flat and can grow to a very large size, up to 0.100 inches in diameter, and drop to the bottom. In a saturated solution, silver ions will recover an electron from an anion as they precipitate to metallic silver. When a silver ion receives an electron from an anion during cooling of a saturated solution, the ion becomes a silver atom. Silver atoms have no ionic charge to produce a repulsive force, so they are draw together by the van der Waals' force of attraction and aggregate into particles of metallic silver. The predominate anions in a silver colloidal solution are carbonate and hydroxide. If the anion providing the electron is a carbonate, carbonic acid is formed which lowers the pH of the solution during this process.

What happens to the silver ions in solution when the water is evaporated?
Silver ions in a solution cannot exist without water, so when the water is evaporated the silver ions (cations) must combine with an available anion to form a compound. The predominant anions present in a silver colloid solution are hydroxide and carbonate. The compounds thus formed are silver hydroxide and silver carbonate. Silver hydroxide is unstable and reduces to silver oxide and hydrogen. The silver carbonate will reduce to silver oxide and carbon dioxide. The final compound that remains is silver oxide.
This process begins as a single silver ion is forced to combine with a single anion forming a single molecule of the compound. The molecule has no ionic charge and therefore no repulsive force. The lack of repulsion causes the molecules to be attracted to each other by van der Waals' force of attraction, which causes them to aggregate and form small particles of the compound. The size of the particle growth is limited by the reduced mobility of the molecules as the water evaporates. What remains is particles of silver oxide whose diameter is 1 - 3 nanometers. It is these particles that predominate in TEM images made of silver colloid solutions which have a high ionic content.

What is a silver solution?
A silver solution contains silver ions in solution with a solvent. The solvent is usually water. A solution which contains only silver ions and no silver particles is a silver solution.

What happens when colloidal silver is ingested?
Upon ingestion, the ionic silver present in most colloidal silver solutions will immediately come into contact with the hydrochloric (HCl) acid that normally exists in the stomach to digest food. The chloride ion from the hydrochloric acid combines at once with the silver ion to form silver chloride, an insoluble silver compound. Since hydrochloric acid does not dissolve metallic silver, the silver particles remain unaffected by the stomach acid. Some of the remaining silver particles, due to their nanometer size will pass easily through the lining of the gastrointestinal tract and will be absorbed into the bloodstream where they will circulate and come in contact with pathogens, which will be killed on contact. The silver chloride that precipitates in the stomach consists of large molecules that flocculate to become even larger particles of silver chloride. Compared to the metallic silver particles, these particles are enormous and will not readily pass through the lining of the GI tract, and thus most will be passed out of the body as waste. Any silver chloride that gets through the lining of the GI tract into the bloodstream will be removed by the kidneys and passed out of the body in urine.

How else can colloidal silver particles get into the body?
Colloidal silver can enter the blood stream directly by at least two different means. The first is through the lungs by using a nebulizer to convert the colloidal silver into nanometer size droplets and then inhaling these droplets. The small size of the silver particles and silver ions will pass through the lung tissue directly into the blood stream. Once in the blood stream, the particles will circulate with the blood but the ions will immediately combine with the plentiful supply of chloride ions in the serum. Human blood serum contains a large quantity of sodium and potassium chloride. The chloride ions are present in the serum in high concentration, typically 3500 ppm. The chloride ions immediately combine with the silver ions to form silver chloride. The large silver chloride molecules will be removed from the blood stream by the kidneys and passed out of the body in urine.
The second way colloidal silver can pass directly into the blood stream is by sublingual absorption. The thin membranes under the tongue will pass the small particles and ions directly into the blood stream. Once in the blood stream, the ions will precipitate out as described above leaving the particles to circulate with the blood.
Because the silver ions cannot exist for long in the human body regardless of the entry mechanism, they really represent an undesired byproduct that is passed from the body as waste. The ideal colloidal silver would maximize the percentage of particles and minimize the percent of ions. Since typical colloidal silver products contain a very high percentage of ionic silver, there is a lot of potential for improvement by reducing the ionic content as close to zero percent as possible.