The Making of Colloidal Silver
— Part 1
Jan 31, 2011 — Updated 04/07/2016
Copyright 2011, W. G. Peters
Colloidal Silver has been made at home with very little equipment for decades. Colloidal silver is well known to be an effective antibacterial, antiviral, and antifungal substance. Silver is appearing in many commercial products, from personal hygiene to washing machines. The EPA has even tried to ban it for fear that it will destroy beneficial microorganisms in the environment.
Unfortunately, homemade colloidal silver is often made incorrectly resulting in the final product being something other than colloidal silver. Usually that is silver oxide or silver chloride, both of which are ionic compounds of silver and which seems to be the product that turns people blue.
It is my intent to show a proven method of making true colloidal silver, and why you should not make ionic silver for internal use.
What exactly is a colloid?
A colloid consists of very small particles of something suspended in another medium. It is not a solution of dissolved material. Fog is a good example of a colloid; it is very fine drops of water suspended in air. Milk is a colloid of very fine particles of proteins and fats suspended in water. With a fine enough filter, the suspended material in a colloid can be filtered out. If the particles in a colloid lump together, the particles will get bigger to the point where they can no longer stay suspended, and they will fall out. If this happens to be fog or a cloud, it becomes rain. Colloidal silver is actually silver nano sized particles suspended in water, usually about 14 nanometers in diameter.
In the case of true colloidal silver, the particles are kept apart by electrostatic repulsion or by a stabilizer. This is true regardless of whether the silver nanoparticles were made by electrochemical or chemical means.
Color of the Colloid:
Another important attribute of a colloid is its color. Milk looks white because the particle sizes in the liquid are at least as large as the wavelengh of red light. The milk particles reflect all wavelengths of visible light, from 400 nano meters to 800 nano meter wavelengths. (A nanometer is a length of 1 billionth of a meter).
When metal particles are much smaller than the wavelength of light, they no longer can reflect all wavelengths, so they are no longer white. At small particle sizes, each metal particle exhibits the Plasmon Resonance1, and absorbs specific wavelengths from the light striking it. This gives the colloid the appearance of the complementary color of the wavelength it absorbed. IE: If the blue light is removed by absorption, the particle will look yellow (green and red are not absorbed, so the resultant color is yellow). The important thing to know about the Plasmon Resonance is that color tells you the particle size of a metal nanoparticle!
Newcomers to making colloidal silver soon learn about the Tyndall Effect. It is the scattering of light by the particles suspended in solution, and typically it shows you have a colloid. Its what allows you to see a flashlight beam projecting in a fog. Its also not very important, and it doesn’t require you to buy a laser pointer; a small flashlight will do. The Tyndall effect really shows turbidity6, which is something which should be minimized in the colloidal silver product. A strong Tyndall effect means there are more particles of larger size. Smaller particle sizes produce less Tyndall effect, so less Tyndall effect is desirable. A Tyndall effect is not necessary to show you have a colloid, as the color from the Plasmon Resonance guarantees that silver nanoparticles are present.
Ionic Silver versus Metallic Silver:
All elements are composed of protons, neutrons, and electrons. When an atom contains the same number of protons as electrons, it is in its elemental state. Silver normally has 47 electrons and 47 protons. Electrons are negative charge, and protons are positive charge, so in an atom of elemental silver, the net charge is zero because each electron is cancelled out by a proton. If an atom of silver were to lose one of its electrons, it would then have a positive charge, and that is called an ion. An ion is an atom which has either gained an electron (becoming negative) or lost an electron (becoming positive). Negative ions are called anions, and positive ions are call cations.
When elements combine chemically, some atoms give up electrons to other atoms. This is what makes a chemical compound. For instance,a sodium metal atom gives up an electron to a chlorine atom to form table salt. When that happens, the sodium becomes ionic instead of metallic.
Why is this important? Most people make silver oxide or silver chloride (ionic silver products) thinking they are making colloidal silver, and while ionic silver is an antibacterial, it is also 25 times more toxic to human cells than metallic silver2. It also seems to be the commonality among the people who have experienced disfiguring Argyria, the permanent blue discoloration of the skin.
The most common method of making silver at home produces silver oxide. But silver oxide reacts strongly with hydrochloric stomach acid producing silver chloride, the silver salt most likely to cause Argyria. For the rest of this article, references to ionic silver means silver chloride unless otherwise noted.
Ionic silver is clear as water. (When overcooked, the ionic silver precipitates though and makes the water gray and cloudy).
How Does Ionic Silver Cause Argyria?
Most people know that film photography is based on silver. In particular, it is based on silver salts5, because silver salts are naturally photosensitive. Film is coated with silver salts, exposure to light provides enough energy to break apart the silver compound in the film producing silver metal. The remaining silver salts which were not exposed to light are then washed away in the development process leaving the dark opaque silver behind as a negative image. A similar process can occur in a person’s skin.
One important difference between metallic and ionic silver is that ionic silver chloride is partially soluble in water. This would seem to be the key as to why Argyria occurs, and why it is permanent. Silver chloride is soluble to .8 parts per million, but some other silver compounds like silver selenide and silver sulfide are not soluble at all.
As a dissolved substance, ionic silver chloride can travel places in the body’s tissues that larger metallic silver nanoparticles cannot because ions are the smallest possible pieces of matter. These silver ions are positive charged and are attracted to human cells which are negatively charged on their outside cell walls. Since positive and negative charges are attracted to each other, the silver ions bind to and enter into the cell wall, carried by metallothioneins. The silver ions then react chemically with sulfur or selenium ions present in the cell creating insoluble silver compounds. At that point, the silver is no longer ionic, and is no longer in solution. It is trapped inside the cell. As these particles accumulate, the cell darkens and result in Argyria. Most of the silver is trapped by a person’s internal organ cells, so even though the skin looks normal, it is quite possible that Argyria is already occurring internally where it cannot be seen. Argyria occurs from the inside out!
It is well documented that the worst discoloration of Argyria occurs in the parts of the skin that are most exposed to light: the face, arms and hands. This is because silver chloride trapped inside skin cells is photosensitive…. its what makes photographic film work. So sunlight can also transform a silver ion into a silver atom, which looks blue black in such tiny particles. Single atoms of metals tend to grow like a crystal as they colllect more silver atoms, and thus grow in size. This is another way ionic silver gets trapped in the skin by converting to metal through exposure to sunlight.
Scanning electron micrographs of biopsies of Argyria victims confirm the presence of silver metal, silver selenide, and silver sulfide in the skin tissues.
The progression from ingesting ionic silver to Argyria is then:
Ingest ionic silver oxide
Silver oxide converts to silver chloride in the presence of stomach acid
Ionic silver is absorbed by tissues and bloodstream
Ionic silver then binds to cell walls by electrostatic attraction
Silver ions enter the cell and are taken up by the metallothioneins.
Silver ions react with sulfur or selenium ions and are permanently trapped in the cell.
Silver ions react to sunlight and are reduced to silver atoms.
Silver crystals form as more silver ions repeat the process.
There are many scientific studies of the properties of silver nanoparticles in the published literature. Almost all that the author has found are in-vitro3 studies exploring the effectiveness of silver preparations and how to produce them. The studies for the most part are done using silver products prepared chemically by the reduction of silver salts using a reducing agent. Few if any have been done using silver produced electrochemically. However it is safe to assume that colloidal silver made electrochemically is equivalent to that made chemically provided the particles’ basic attributes of size and shape are the same. Because the vast majority of serious research is done in-vitro, there is little real data concerning real life dosing, and results. Most of the information about using colloidal silver internally is anecdotal. There is a published peer reviewed study showing that silver nanoparticles are more effective for bacteria and fungi than ionic silver.
“Interestingly, AgNP’s have been shown in a variety of cases to be more toxic to bacteria and fungi than free ions”7
It will be left to the reader to seek out the published literature if so desired.
There seems to be hundreds of manufacturers of colloidal silver, each touting their own special formula. Some of these sources make excellent product and some are very dubious. One thing is clear though: Colloidal silver is only cheap if you make it yourself.
Even at $50 an ounce for silver, a 16 ounce bottle of 20ppm colloidal silver has less than 2 cents worth of silver in it. Quality colloidal silver can be made at home with a very modest investment. $100 worth of supplies will probably last a lifetime.
Thoughts on dosing:
As said previously, there is little to no scientific studies regarding dosing, or what happens in-vivo4 when colloidal silver is consumed. However, some of the in-vitro data may be useful. One of the important pieces of information is the concentration of silver required to kill bacteria. Two to six ppm seems to be the minimum for most bacteria in lab experiments. It seems safe to suppose that less than that would not be effective in the body. (One ppm is one milligram of silver in a liter of water.)
It seems sensible to assume that disease agents travel around the body in the blood and lymph, the primary fluids which flow within all parts of the body. Considering then that the average person has 5 liters of blood, it would then seem that a dose large enough to kill bacteria in the blood stream would be at least 10 milligrams of silver. This would be the amount of silver in about one pint of 20 ppm colloidal silver.
Calculating dose based on blood volume would be an ideal way to get a handle on dosing except that we do not know how much of the silver ingested actually is absorbed and enters the bloodstream, and if that silver entering the blood stream is still of a size that has therapeutic value. As soon as the colloidal silver enters the body, some will be absorbed through the mucosal lining of the mouth and esophagus, but the remainder is soon mixed with hydrochloric acid plus a host of other chemicals in the stomach. Acids and other electrolytes destroy the electrostatic repulsion between the silver particles and allow them to aggregate into larger particles which would make them useless. The actual amount of silver which enters the bloodstream would then be affected by anything which affects the chemistry of the stomach. So dosing is still a guess, but we do have a good idea about the minimum dose. As a personal choice, the author arbitrarily doubles the minimum amount and takes 1 liter of 20 ppm silver over the course of a day when needed. No antibiotics including silver should ever be taken without good cause.
It is obvious then that taking a teaspoon a day as a food supplement is probably not going to do anything therapeutic, unless the placebo effect is considered therapeutic since the amount would be far below the concentration needed to kill bacteria or other microorganisms. Silver is not a food, and is not essential to life. Consuming small amounts of silver as a food supplement has no documented and proven health benefits.
In the next part, we will talk about various ways to produce true colloidal silver.
1) Plasmon Resonance: Resonant oscillation of the surface electrons of metals at visible light frequencies. Resonant frequency depends both on size and shape of the particle and contributes to the observed color.
2) Antibacterial activity and toxicity of silver nanosilver versus ionic silver, Libor Kvitek LINK to pdf file
3) In-vitro: research done in a test tube environment — literally, ‘in glass’ as opposed to within a living organism.
4) In-vivo: Within a living organism
5) Usually silver chloride, silver bromide, or silver iodide.
6) Turbidity is the cloudiness or haziness of a fluid caused by individual particles (suspended solids) that are generally invisible to the naked eye,
7) Advances in Applied Microbiology Vol. 77 By Allen I. Laskin, Geoffrey M. Gadd, Sima Sariaslani
Jan 30, 2011 Updated Oct 29, 2015
Copyright 2011, W. G. Peters
The goals for a colloidal silver production method for personal use should include:
- High quality
- Consistent concentration (ppm)
- Short processing time
- No toxic chemicals
- Optimum particle size
- Inexpensive equipment
Common Method Used Today:
Most of the home made colloidal silver made today is made by the electrolysis process where two silver wire electrodes are inserted into cold water and an electrical current is passed through the electrodes from a battery or other power supply. This is the method which is commonly known, and done with a couple of nine volt batteries and pieces of silver wire.
If this simple process is done, it fails to meet any of our production goals. It does not even meet the goal of “no toxic chemicals” because the process itself creates the chemical silver oxide which as has been explained may cause Argyria. What it does create is an ionic solution of silver oxide and some colloidal silver oxide (very large particles of precipitated silver oxide).
Worse yet is that most people think you should shine a laser beam through the water looking for the Tyndall effect. Good 20 ppm ionic silver will show no Tyndall effect, and if you get one, it means your silver is already overcooked and bad.
Even worse is if salt is added to ‘start the process faster’. Adding salt with this simple method cold only creates large amounts of silver chloride, which again is implicated in causing Argyria.
A much better way:
To make colloidal silver correctly, safely, and repeatably, here is the process.
You will need:
- .999 pure silver wire or a pure silver bullion coin. These are readily available.
- Pure steam distilled or de-ionized water. Steam distilled is preferable.
- Light corn syrup (Karo), or other reducing agent.(reducing agent)
- Sodium carbonate (washing soda)(electrolyte)
- Constant current or computerized generator with at least 3 ma current.
- A fixture to hold your electrodes to approximately 1.5 inches/37mm apart.
- Glass container, like a canning jar (Mason/Ball)
- Inexpensive milliammeter
Mix up the corn syrup with an equal amount of distilled water. This will be the reducing agent which converts ionic silver to true colloidal silver. Make 1 or 2 ounces, as you will only need a few drops of this mixture per gallon of water.
Mix up the sodium carbonate by dissolving 1 level tablespoon in 3 ounces of water.*
Starting with 1 liter of water, add 20 drops of sodium carbonate solution. Sodium carbonate is what you get when you bake baking soda, so you have consumed a lot of this in your life, and it is not toxic. Mix well.
Insert your electrodes into your fixture and then into the water. Turn on the power. Put as much of your positive electrode into the water as possible without getting the lead wire wet if using a bullion bar, and no more than 1/4 inch of the negative electrode to start.
Using a milliammeter, measure the current through your electrodes and if the current does not reach the set point of the generator, you can insert more of the negative electrode into the water to increase the current and insert less to raise the cell voltage which must be at least 10 volts for best results. If using silver wire for your electrodes, your generator should be set to no more than 6 ma unless you have a magnetic stirrer 3ma would be better. If using a 1 ounce bullion coin, it should be no more than 15 mA. These currents can be increased if you have a sufficiently strong stirrer. The distance between electrodes should be about 1.5 inches (37mm).
Calculate the required time to make 20 ppm based on the formula that 1 milligram of silver will enter the water for each 15 milliAmp minutes of process time. 15 milliAmp-minutes could be 1 mA for 15 minutes, 2 mA for 7.5 minutes, 15 mA for 1 minute, etc.
20 ppm is 20 milligrams of silver per liter. So for example, if you only wanted to make 250ml, you would only need 5 milligrams of silver, and 5 * 15 milliAmp-minutes of current.
When the required time has elapsed, turn off the power, remove the electrodes, and add 2 drops of the corn syrup solution to the water and heat it to at least 140 degrees F. In a few minutes, it will change from crystal clear and colorless to crystal clear but yellow colored. This color change is the proof that the ionic silver has been converted to true colloidal silver.
Time required for 1 liter of 20 ppm Colloidal silver at various constant currents:
Current mA Time minutes
For quarts instead of liters, decrease time by 5%
You can calculate the required time for other amounts and currents from this formula:
minutes = milliliters * ppm * 0.015 / milliAmps.
minutes = liters * ppm *15 / milliamps
This is the basic method. There are variations on this method, using hot water vs cold, different reducing agents etc, but this method always produces quality 20 ppm colloidal silver and is recommended as a starting point for beginners interesting in producing the best colloidal silver possible. Higher strengths are possible, but need some additional equipment and other food items.
* Amount shown is for Arm and Hammer Super Washing Soda. If you have an accurate scale, the correct amount is 12.4 grams with enough water to make 100ml.
Copyright © 2011 W. G. Peters
The electrolytic process for making colloidal silver requires an electrolyte to work. Even pure distilled water with nothing added to it acts as a weak electrolyte because a very small amount of pure water disassociates into H+ and OH– ions. You might say that a certain amount of water dissolves in itself as hydrogen hydroxide. A liter of pure water will contain 10-7 moles1 of hydrogen ions, and 10-7 moles of hydroxide ions. This amounts to 0.0017 milligrams of hydroxide ions, but this tiny amount is enough to make silver hydroxide when you put silver electrodes in the water and connect them to a battery. These hydrogen ions and hydroxide ions are the current carriers which allows current flow through the electrolysis cell, but so few carriers result in a very weak current. A weak current results in a long process time.
Aside from the long process time, using the hydroxide inherent in pure water as the electrolyte has another problem. The amount of hydroxide is not constant, but increases as the amount of silver hydroxide increases. This creates a run-away process that gets faster with time, and therefore is difficult to control as anyone who has used this simple process can attest.
We can solve these problems by adding an appropriate electrolyte to our water. A useable electrolyte must have certain characteristics. It must be non-toxic above all else. It must not form any toxic byproducts. It must form a soluble compound with the silver anode. It should be safe to handle. It must dissociate in water (ionize). Its positive ion should not plate out onto the cathode. It should be inexpensive, and readily available. These requirements reduce the number of choices considerably.
In choosing the specific compound to use, toxicity is paramount. Luckily substances normally found in human physiology are good candidates. Chlorides, citrates, gluconates and hydroxides and carbonates are all non-toxic anions3 especially in the low concentrations we need. Chlorides are everywhere in the body, and citrates are an integral part of the citric acid cycle which provides our energy. Gluconates are commonly found in foods. Hydroxide is a natural constituent of water. The body is very adept at handling these substances.
There are only two very common bio-compatible substances which will inhibit plateout onto a cathode. They are sodium and potassium. Both of these ions react strongly with water as soon as they are reduced to metal at the cathode, and create hydroxides which are water soluble. So, the sodium or potassium stays in solution as ions. Because of this, a sodium or potassium compound would be ideal for making colloidal silver electrolytically. An added benefit of using sodium compounds is that it is self replenishing. The sodium ions that contact the cathode are immediately reduced to sodium metal, and then react with the water to become sodium hydroxide. The net result is that the electrolyte is never used up.
For these reasons, a very good choice of an electrolyte is sodium carbonate, commonly known as washing soda. It is cheap, readily available, and it works extremely well for making colloidal silver. It is also safe to handle. Everyone has consumed sodium carbonate, it is what results from heating baking soda, so is a common ingredient in baked goods. Sodium carbonate is the salt of a strong base and a weak acid. When dissolved in water, it creates sodium hydroxide and carbonic acid. Very little of the the carbonic acid actually ionizes, and exists as carbon dioxide dissolved in the water…. like soft drink. The net result is that the sodium carbonate liberates mostly sodium and hydroxide ions., not carbonate ions.
While baking soda could be used, it is not nearly as good because it produces only half as much sodium hydroxide and also produces more carbonic acid. However, it is very easy to convert baking soda to sodium carbonate (aka washing soda) simply by baking it. When baked, baking soda gives off carbon dioxide gas and water vapor which is what makes baked goods rise.
When using sodium carbonate as an electrolyte, the MINIMUM theoretical voltage needed is 3.5 volts. Below this there is not enough voltage to reduce the sodium at the cathode and oxidize the silver at the anode. This comes from the electrochemical series which describes the voltage a metal creates when used with a different metal in an electrolytic cell (battery). Experiments I have conducted seem to confirm this. The sodium ion requires -2.71 volts to force an electron to it, and the silver atom requires 0.8 volts to remove an electron from it. So the total is 3.51 volts. In practice, the voltage should be several times this minimum because there is voltage lost in the bulk water itself. 10 volts is a good minimum across the electrodes producing satisfactory results, but I have found that higher voltage is always better. However, the improvement is not linear. IE: 10 times the voltage does not provide a ten fold increase in quality or efficiency. Anything over 20 volts is probably not very beneficial with an electrode distance of 1.5 inches. Wider spacings or different electrode geometries will require higher voltage for the same result.
Using sufficient sodium based electrolyte keeps most of the silver from plating onto the cathode. The positive ion with the lowest redox potential from the electrochemical series will selectively plate out. Since sodium’s redox potential is -2.71 and silvers is +0.8, the sodium ions keep the silver from plating onto the cathode. There is a correct amount of sodium carbonate which also produces the optimum pH (8.5) of the water. This amount is 106 milligrams of sodium carbonate per liter of water.
Reducing agents are necessary if one wishes to make non-ionic colloidal silver. While heat alone can accomplish this, the process is slow, and not always complete. Also, it is impossible to make higher ppm concentrations of silver using heat alone as the silver oxide exceeds its solubility and precipitates out before heat reduction occurs.
As with electrolytes, the non-toxicity of a reducing agent is the first consideration. I pondered this for a long time until I realized that any food we eat will undergo chemical oxidation by the body. The body knows quite well how to handle the oxidized byproducts of metabolism. This means that if the food is non-toxic, so will be its reduction/oxidation products. Luckily, there are many sugar based and other food products which are reducing agents and work with silver. The quality of the product differs with choice of reducing agents in that some produce more consistent particle sizes, some work faster, and some produce more stable product. Agents which have shown to work are glucose, corn syrup, pure light honey, maltose, maltodextrin, and cinnamon extract. Tea is also a reducing agent, and has been shown to reduce gold. So far, one of the best ones I have found is clear corn syrup. Corn syrup is a 50/50 mixture of glucose and maltose plus water. Both glucose and maltose are reducing agents for silver. Ordinary table sugar (sucrose) does not work, nor does ordinary starch.
When the process is complete, and all of the silver ions are reduced, the solution will contain nothing toxic.
For any of these agents to work, the pH of the solution must be basic (above pH 7). pH above 7 opens up the ring structure of a glucose molecule activating it as a reducing agent. Using sodium carbonate as an electrolyte automatically raises the pH sufficiently to activate the reducing agent.
One ml of 1 Molar sodium carbonate per liter/quart is a very good amount to use, as it is sufficient to prevent plateout, sufficient to activate sugar based reducing agents, and provides plenty of conductivity. Note that different size dropper tips will dispense more or less liquid, so you can calibrate your dropper by counting the number of drops required to fill a teaspoon with your electrolyte and divide that by 5.
1) A mole of any substance contains approximately 6 x 1023 molecules, and weighs the sum of its atomic weights in grams.
2) Coffenol developer contains Folgers instant coffee, vitamin C, and baking soda.
3) Anions are ions which are more negative than the anode. Cations are ions which are more positive than the cathode.
4) It gives the salt and vinegar flavor to certain brands of potato chips.
Colloidal Silver Chemistry
Colloidal Silver is a popular home remedy for a host of ailments. It can be purchased at health food stores, and of course on the internet. It is expensive though considering a pennies worth of silver may cost $10.
For that reason, many people attempt to make it themselves through a simple process of electrolysis. The most common method is simply to put two silver wires into a glass of water and connect the wires to a couple of 9 volt batteries. There are two important variations in the process though, one very good, and one very bad. There are much better ways to make colloidal silver, which are covered in another article.
So what do most people actually make and call Colloidal Silver?
Well, that depends on the method they use. Here are the three main methods I hear of people using and the method most researchers use:
I) Distilled water + silver anode at room temperature.
In this method, free hydroxyl ions (OH–) in the water initially react with the positive silver electrode to make silver hydroxide (AgOH). Starting with pure water, and pure silver, Silver hydroxide is the only product that can be initially made. Silver hydroxide is unstable though and rapidly decomposes to silver oxide Ag2O. If you remember your high school chemistry, the reaction forumula would be:
2AgOH –> Ag2O + H2O
Silver Oxide is slightly soluble in water, and after electrolyzing for a while you have an ionic silver solution, not colloidal silver. You can prove that silver ions exist at this point by adding a small amount of table salt as a test. The salt will form silver chloride which will precipitate out to form a cloudy liquid because the solubility of silver chloride is 25 times less than silver oxide.1
If the electrolysis is continued, the silver oxide will reach saturation, and then will start to precipitate as colloidal silver oxide. At this point, the solution will start to show the Tyndall effect. This is not strictly colloidal silver, although it does have anti-microbial properties according to the EPA2 Silver oxide is what gives the solution its metallic taste which is another indication you have made silver oxide instead of colloidal silver.
This is what most people make and erroneously call colloidal silver. Once swallowed and mixed with hydrochloric stomach acid, the silver oxide reacts with the acid producing silver chloride. Once absorbed into the bloodstream, it can travel into the skin and other tissues where it can further react with selenium and sulfer compounds forming silver selenide and silver sulfide. Scanning electron microscopy studies of Argyria victims show that the silver trapped in the skin is predominately silver sulfide and silver selenide, so it is highly likely that ingesting large amounts of ionic silver will eventually lead to Argyria.
II) High Temperature Colloidal Silver method
If the same method as above is performed while the water is close to boiling temperature, an additional reaction happens. Silver Oxide reduces to metallic silver when close to boiling in the absence of free oxygen3 and in the presence of hydrogen gas. Hydrogen gas is generated at the cathode by the reaction of reduced sodium and water or by the electrolysis of water if no sodium is present. This makes a straw colored colloidal silver product. The yellow color is caused by the plasmon resonance effect of the extremely small metallic silver particles.
The spontaneous reactions that reduces the silver oxide to silver are:
Na+ +e –> Na (metal) (e = electron and comes from the cathode when the sodium ion touches it)
2Na + 2H2O –> 2NaOH + H2 (gas)
Ag2O + H2 –> 2Ag + H2O
This reaction is usually not complete because some of the hydrogen gas is lost by escaping from the water.
The result is then a solution containing very little silver oxide (ionic silver) and a majority of metallic silver particles.
III) Distilled water + salt + silver anode.
Some people add a little table salt to jump start the electrolysis process. This method produces silver chloride, which has very low solubility and thus produces a cloudy solution. Silver chloride is very photosensitive, and is used in the production of photographic paper. When ingested, silver chloride ions travel into the skin, and are photo reduced by sunlight to insoluble silver, or chemically reacted with sulfides and selenides to insoluble silver compounds which then becomes trapped in the skin and cannot be removed.
IV) Reduction of Silver Salts (compounds) with a Reducing Agent
Not many home brewers use this method, but it is the method of choice with professional researchers, as it is quick, highly repeatable, and highly controllable. The great majority of data showing that silver is effective against pathogens was done using colloidal silver made by the chemical reduction of silver salts (compounds). This method produces true silver nanoparticles with no ionic content. Typically, a soluble silver salt, such as silver nitrate is reduced to silver metal particles using an agent such as glucose. The technique can be combined with home methods easily though just by adding a small amount of a suitable reducing agent to their water. Suitable reducing agents for at home use include light corn syrup (glucose maltose mixture), maltose, Golden or King syrup, maltodextrin, or glucose. These are all foods or food additives, and do not create any toxic byproducts.
V) Electrolysis Combined with a Reducing Agent
This is the method I favor, as it is simple, reliable, uses no toxic chemicals, and produces true silver nanoparticles. It does require some specialized equipment (quality generator). Instructions and details can be found in the cgcsforum.com main site.
Which method is better?
Definitely not method III, with salt. Ingesting silver chloride is simply asking for trouble in my opinion.
Method I, the most common way of making colloidal silver would seem to be safe however the product does not remain silver oxide when ingested. The stomach is a chloride rich environment which will convert silver oxide to silver chloride as soon as it is swallowed. Do people take enough silver oxide to be a problem? I don’t know. Perhaps silver chloride is not readily absorbed by the body, but then why is that the people who developed argyria have used salt to make their colloidal silver? Maybe its simply the dosage.
The best method is one which produces no ionic content, as true colloidal silver will not react strongly with stomach acid to make silver chloride, and it has an excellent shelf life, even when exposed to light. I have a sample several years old in a clear glass bottle exposed to light every day, and it has not yet degraded.
A recent published report showed that ionic silver is toxic to human cells. There is no scientific evidence that consuming ionic silver has any benefit, and the anecdotal reports that ionic silver is therapeutic are almost certainly the result of the placebo effect. That would seem to suggest again that metallic colloidal silver would be the far better choice to take internally.
1) Solubility of silver species
Silver Oxide Approximately 0.00250 g/100 ml (20C)
Silver Chloride Approximately 0.00052 g/100 ml (20C)
2) US EPA Registration Review Schedule: Antimicrobial Pesticides of October, 4, 2006
3) I first discovered this when attempting to make colloidal silver using one submerged silver electrode, and one silver electrode suspended 1/8th inch above the water. I then applied 4000 volts from a transformer to create a plasma arc from the suspended electrode to the water surface. This created a clear colloidal silver (as tested by the salt method). I noticed that after a time, a yellow to brown layer would form at the top of the solution as it heated up from the plasma arc. As the arc continued to heat the solution, the brown layer would grow further down from the top. I did not know why until recently when I found reference to the decomposition of silver oxide to pure silver at boiling temperature in the absence of oxygen.
Until the digital age, photography was mainly based on silver emulsions. Here’s how it works.
First, the emulsion is usually a silver halide, like silver chloride, or silver iodide, but most low solubility silver salts1 work. This silver salt is in the form of crystals. The grain size of the crystals determines the ASA index (like ASA400) or speed of the film.
When a photon of light strikes a molecule of silver salt in the emulsion, it knocks free an electron. This free electron can then reduce another silver atom.
A single silver atom is not stable for very long though, and will recombine with another anion in a short while. However, if enough photons strike enough silver salt molecules, more silver atoms will be reduced. If there are at least 8 silver atoms nearby, they will combine to form a stable silver seed particle. 8 silver atoms become stable because they can share their outer electrons making each atom see a full outer electron shell. (Some say it only takes 4 silver atoms to be stable because silver can also share 3 electrons, so 2 atoms sharing 3 electrons together with 2 atoms sharing one would make up the required 8 electrons for stability. It doesn’t matter to this discussion whether 4 or 8 are required. )
So the stronger the light impinging on the emulsion, the more silver seeds are produced within each crystal of silver salt.
At that point, the emulsion contains various amounts of silver seeds where exposed to light, and none where no light struck.
Now comes the fun part, development.
Silver metal is a catalyst for many chemical reactions. A catalyst is a substance that aids other chemical reactions, enabling them or speeding them up without being changed or consumed in the process. When a weak reducing agent is introduced to the silver salts in the emulsion, the silver salt crystals which have been exposed to light, and contain silver seeds will reduce to pure silver metal much more quickly than silver salt crystals which do not contain silver metal seeds. So the development must be timed correctly as eventually all the silver salts would be reduced destroying the picture.
Once the development is complete, the reducing agent is destroyed by the acid ‘stop bath’, and then the remaining silver salts are washed away with the ‘fixer’ leaving only the silver metal particles in the film.
Now, applying that knowledge about photography to making colloidal silver, what happens?
If the ionic silver solution (silver salt) is exposed to strong light, it will create silver seed crystals. These seeds will catalyze the reduction reaction in their vicinity causing the ionic silver in their vicinity to quickly reduce and combine with the seed. This makes a larger particle. The more seed crystals, the more larger particles will be produced. This is not what we want. We want all the silver to reduce uniformly and fairly slowly. Its also the reason why commercial ionic silver is sold in brown glass bottles.
Silver is most sensitive to ultraviolet and blue light. That’s why darkroom lights are red. Therefore, its best to keep ionic silver out of strong light, especially sunlight and fluorescent lights because they both have strong ultraviolet content.
1) Salt in this context means any silver compound
source: https://www.cgcsforum.com – Kephra