Build a Colloidal Silver Maker

What is Colloidal Silver and What is it Used For?

Definition: Colloid - Physical Chemistry. a substance made up of a system of particles with linear dimensions in the range of about 10 −7to 5 × 10 −5cm dispersed in a continuous gaseous, liquid, or solid medium

For those of you who may not be aware, silver is an antibacterial agent. The use of silver in medical applications dates back all the way to the time of Hippocrates, who wrote about the use of silver in wound care. Although silver is still used today for some medical applications, colloidal silver is not approved by the U.S. FDA. I couldn't find a source but I recall reading that the Bubonic Plague that wiped out millions in the middle ages hit mostly working class people, in part because the wealthy ate using silverware.

Regardless of what the FDA says or "Big Pharma" studies indicate, my own personal experience is colloidal silver is effective for combating infections. A few gulps of it will often eliminate a sore throat, as it did for me this morning.

Essentially, colloidal silver is a solution of water with a trace amount of pure silver in it. It can be made through the process of electrolysis using a very small amount of electrical current with pure silver electrodes immersed in distilled water.

A very crude colloidal silver maker can be constructed with 9 volt batteries and pure silver electrodes in water, however that method must be monitored or you will end up with a brown liquid with a high concentration of silver clusters which are far bigger than your body can effectively use. The amount of silver in the solution increases rapidly with time, because silver is conductive, causing positive feedback such that as the silver content increases so does the current, resulting in large clusters of silver atoms rather than a colloidal solution.

You can easily find colloidal silver machines as well as colloidal silver on the market. A local friend of mine bought one and it cost her $300 over 10 years ago. She allowed me to take it apart to see how it was built. Its' primary component was a common LM741 op amp IC which was configured as a constant current source. It also used a few transistors along with various passive components. I felt it was greatly overpriced, but at least it was well constructed, far better than many on the market that rely on you timing the process to determine the PPM (parts per million) potency.

The Design
I designed this "CS Generator" with 3 primary concepts in mind: 1) It must use a very controlled amount of current for electrolysis, 2) It must provide a way to circulate the solution during production and 3) It must shut off automatically. I had just moved, and most of my supplies and tools were still packed away, so the construction is not the best example of my work. Nevertheless it has served me well over the years and I suspect it will for the rest of my life.

Here is the schematic and PCB artwork for the design:

Q1, R1, R2, R5, D1, D2 and P1 form the constant current source. The amount of the current is determined by the values of R2 and R5 which set the maximum possible current. Potentiometer P1 is adjusted to vary the current, which controls the rate of electrolysis.

IC1, Q3, P2, R5, R6 comprise the monitoring and shut off functionality. The open collector LM311 compares the voltage on the non-grounded silver electrode which reflects the conductivity of the solution and thus the concentration of silver in it. Resistor R5 pulls pin 7 of IC1 up to near the supply voltage when the comparator is off and R6 provides a small amount of negative feedback to prevent oscillation during switching.

Once the voltage on pin 2 of IC1 goes more positive than the reference voltage on pin 3, set by potentiometer P2, the comparator turns on bringing pin 7 to ground, turning off the constant current source. This also causes the cathode of LED2 to swing negative to light the "Complete" LED, as well as turning off transistor Q3 which disables the stir motor and "Active" LED1. Diode D3 protects Q3 from any back EMF "kickback" that may be produced by the inductance of the stir motor. Capacitor C1 filters any noise that might trigger premature completion.

The stir "motor" is a little vibrator device I pulled from an old cell phone. It's the little round thing dangling between the two electrodes by a very flexible wire, and helps to circulate the solution while electrolysis is underway. You can actually see the wire is blurry in the picture of the electrodes.





You can see the internals here on the right:






Here is a closeup of the silver electrodes. I cut a .9999 pure silver round in half and drilled a small hole in each to attach the wire leading up to the control box. I sealed everything with plumber's goop. BTW, that's actually a brand name if you didn't know, and works very well, but you should use it with good ventilation as the fumes are very pungent and toxic to breathe.




I also added two test points I can measure the shutoff threshold and solution voltage near the power connector. I used a "wall wart" power supply from an 18 volt Harbor Freight Tools cordless drill which I modified to add filtering and provide the yellow and white leads to power the generator. I never got around to adding a proper connector for the power, which is why diode D4 was added in case I plugged the power connector on wrong.

I calibrated my unit in terms of the PPM strength of the solution it produces against my friends unit. The red marks can be seen on the current adjustment and a lighter mark on the shutoff threshold. That's about it. Thanks for reading!