Concepts of Biology:  Professor Ben Aronson
                             From the University of Redlands

Introduction
Materials and Methods
Results
Data of Results
Pictures of Results
Discussion of Results

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       Antibiotics have been used over the past decades to kill bacteria that cause illnesses. They also range in their effectiveness in killing bacteria. Furthermore, antibiotics differ in the types of infections they can treat by killing bacteria that can cause many common illnesses, like salmonella and bladder infections.
        One new liquid drug solution, Colloidal Silver, has made claims on its website that it kills bacteria more effectively than other antibiotics, and claims to not have any side effects that are associated with other antibiotics. In essence, Colloidal Silver is considered a miracle drug by many websites that sell the drug.  One of Colloidal Silver’s websites http://www.utopiasilver.com  states that Colloidal Silver has not undergone any testing like well known prescription antibiotics such as Amoxycillin. Despite the fact that the drug has not undergone formal testing, the website attests that the drug can cure many common and not so common ailments.  For example, this site claims that Colloidal Silver can treat anthrax, allergies, acne, warts, athletes foot, and many other medical conditions. Colloidal Silver also doesn’t require a prescription. Experiments were done in lab to test the validity of the claims presented on the Colloidal Silver website on whether it is effective as antibiotics in killing bacteria. 
        In  lab experiments, flies, bacteria, and the most commonly used antibiotics (Kanamycin, Streptomycin, and Ampicillin) were used along side with Colloidal Silver.. The experiments were done to see whether Colloidal Silver could prove to be more or as effective with commonly used antibiotics. The flies were used in the experiments to determine whether Colloidal Silver has any toxic effects and if it killed any of the fly’s bacteria.  In all of the experiments done, Colloidal Silver had the least or none of the anti-bacterial killing properties that the other prescribed antibiotics that were used in our experiments. This data proves that it is more effective to use medically prescribed antibiotics. Numerous tests have been done in class on colloidal silver in relation to other antibiotics like Kanamycin, Ampicillin, and Streptomycin.

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                                                         Culturing Flies to Test the Toxicity of Colloidal Silver

      Two vials approximately three inches tall and one inch wide in diameter were used in this experiment. In each vial, one cup of fruit fly 
food was added. Approximately one cup of sterile water was added to the first vial, while the second vial had one cup of Colloidal Silver.
Flies were placed into the vials via small paintbrushes. Both vials were capped with sponges to prevent flies from escaping. 

                                                                                      Culturing Bacteria

     Flies were initially placed into small eppendorf tubes, and then crushed by pestles. Twenty fruit flies were pipetted  into each of the two vials. 
The C 600 bacteria was first pipetted at a 20/200 ratio from a vial into the center of petri dishes. Then a spreader was dipped in alcohol and 
placed into a flame of a Bunsen burner for a short amount of time to sterilize the spreader. The spreader was then used to disperse the bacteria 
evenly in the petri dishes. Application of the antibiotics on the petri dishes were done in the same manner as the bacteria. The dishes were then 
placed in an incubator with varying temperatures depending upon the experiment in order to facilitate the growth of bacteria. 


                                                                                        Fruit Fly Vials					                                                                               

     Two squirts of water (equivalent to one cup) were used as well as one cup of fly food in a vial, labeled as Vial #1 -- Water Food. 
Then mixed one cup of Colloidal Silver and one cup of fly food in another vial, labeled as Vial #2 Colloidal Silver Food.
The dry fly food was supplied from Carolina Biologicals. Forty flies were counted that were beforehand put into a “fly nap”. The flies
were separated into two groups of 20 by use of a paintbrush. Twenty flies were placed in Vial #1. The flies were put outside of the 
food, with the tube laying sideways, so they wouldn’t be immobilized by the food being stuck to them. The other twenty flies were
placed in Vial #2.      

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     For this experiment two vials contained flies one of the vials had water food, while the other vial had Colloidal Silver. The flies were tested to determine the level of toxicity. The number of dead flies in the Colloidal Silver vial exceeded the number of dead flies in the untreated vial. (see Graph 1 and Graph 2). Therefore, Colloidal Silver showed some level of toxicity. The dead flies were taken into account. Eight flies were dead in the water food, (untreated vial). Eight flies were also dead in the Colloidal Silver vial . The flies that were dead in the vials were cultured and tested for quantities of bacteria present, in order to clarify if Colloidal Silver decreases the number of bacteria in another organism. The flies were counted in six days, and eight were still dead. The Colloidal Silver vial  had six flies that were dead. 12 living flies were left in Vial #1 [Water Food] and 14 flies from Vial #2 [Silver Food]. The data implied that Colloidal Silver showed toxicity.

                                   Comparison of Bacterial Colonies In Colloidal Silver Dishes versus Fly Food Dishes

     For this experiment smashed flies that were taken out of a vial of the fly food and a vial of Colloidal Silver. These smashed flies were then placed into petri dishes and  incubated. Bacteria was then counted to determine the difference between flies treated with Colloidal Silver and flies that lived on water food.  There was a small difference between the bacterial colonies in Colloidal Silver dishes versus the bacterial colonies in the fly food dishes when counted (see Graph 3 and Graph 4). Therefore, Colloidal Silver does not show a significant decrease in the number of bacteria in an organism.

     The first ten dishes added together equal 2,829,840 colonies.  This number divided by the total number of dishes of that type is 2,829,840 / 10 = 282,984 colonies of bacteria per fruit fly in Vial #1 [Water Food]. The second ten dishes added together equal 3,905,630 colonies. This number divided by the total number of dishes of that type is 3,905,630 / 10 = 390,563 colonies of bacteria per fruit fly in Vial #2 [Silver Food]. The average amount of bacteria in each fly that was originally in the Colloidal Silver was greater than those flies from the normal food. These results conclude that Colloidal Silver does not decrease the number of bacteria in another organism.

                           Colloidal Silver vs. Kanamycin, Colloidal Silver vs. Ampilicin, and Colloidal vs. Sterile Water  

     By measuring the diameter of the colonies killed by Kanamycin, Ampilicin, and Colloidal Silver; Colloidal Silver was found to be a more efficient antibiotic. Twelve petri dishes were spreaded with 20micro-liters of C600, and were used with different full strength and diluted forms of antibiotics to see whether one had a better killing range than the others.  Two were for 10microl of Kanamycin, two for 10 of Ampicillin, two for Colloidal Silver, and two for sterile H2O (a control).  Then the same was done, but in diluted versions in the ratio of 10/50, except for the control H2O.  By spreading the different antibiotics and letting them stay heated to normal body temperature, Kanamycin appeared to work the best.  The diameter had the largest area of killing of the bacteria than the rest. Ampilicin worked second best, while Colloidal Silver had the smallest zones of killing. (see Graph 5).  The Colloidal Silver was no more effective in killing bacteria then sterile water control. The diluted Kanamycin had a larger diameter of killing, and in turn killed more bacteria than the diluted Ampicilin.  Both diluted antibiotics were more effective in killing bacteria then full strength Colloidal Silver. 

                           The Effectiveness of antibiotics, sterile water, and Colloidal Silver to kill the bacteria C 600

     By spreading C 600 and the same amount of different antibiotics, including Colloidal Silver, on a petri dish, different amounts of killing were observed.  The various ranges of killing are marked below with a blue arrow. The blue arrows points to the area on the petri dish where the C 600 has been killed, or at least reduced significantly.  The darker areas of the dishes are where the C 600 grew, and sometimes where the antibiotics were not placed.  In certain cases, with Colloidal Silver and sterile water, no lighter areas of the dish are found because they were not effective in killing the C 600.  Except in one case of Colloidal Silver, ( as shown in Picture B), in which some killing was observed.  Other than that the other antibiotics used proved much more effective than Colloidal Silver.

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                                        Graph 1

Graph 3

Graph 4

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                                 Picture A
This picture depicts Streptomycin's ability to kill bacteria.
The lighter section in the middle shows the zone of killing,
where C 600 has been eliminated. 

                               Picture B
This shows the same thing as Picture A, however, Colloidal Silver is being used.

Picture C

Picture D

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          The testimonials (http://www.utopiasilver.com/stories.htm) on the official Colloidal Silver website are not accurate, Colloidal Silver is not as effective in killing bacteria as the website leads you to believe. The main claim presented on the colloidal silver website is that colloidal silver kills bacteria consistently. Three other antibiotics that were used in past labs were more effective in killing bacteria over colloidal silver. These include Kanamycin, Streptomycin, and Ampicillin. Kanamycin was the most effective of three antibiotics listed above. Kanamycin discontinued the progression of the bacteria C 600, which is an E. Coli bacterium. Ampicillin was the second most powerful antibiotic, for its ability to kill the C 600 bacteria was not on par with Kanamycin. Streptomycin was the least powerful in stopping or killing the bacteria in comparison to Kanamycin and Ampicillin.
           There were several possible discrepancies that were discovered during our lab experiments with Colloidal Silver. One possible discrepancy that was discovered was possibly do to improper spreading. Improper spreading occurs when the bacteria and antibiotic are  not evenly dispersed onto petri dishes.  This discrepancy causes areas where bacteria and Colloidal Silver are not in direct contact with each other. Another possible discrepancy could have been from pipetting too much fly liquid onto the plates. The amount could have been smaller (5 micro-liters) to insure a more accurate count of the bacteria present, for it was difficult to determine the number of bacteria killed in the plates based on the exorbitant amount of  bacterial colonies. To determine the amount of bacterial colonies, a square approximately one centimeter by one centimeter was created (reference square). The amount of other one by one centimeter squares that could be possibly formed out of a given petri dish was multiplied by amount of bacteria found in the reference square. This method of counting bacteria could have been more accurate if the reference squares were smaller then one by one centimeter. They could possibly be .75 * .75 centimeters instead.
          The most common use of Colloidal Silver is as an antibiotic, which is what all the experiments were tested for. There were no tests on how Colloidal Silver could be used against viruses. The Colloidal Silver website claims (www.utopiasilver.com) that it can kill common viruses like the cold or flu. This could be tested in the manner as the experiments involving C 600.  The only difference would be a substitution of C 600 for a sample of a particular virus. The sample of the virus could be extracted from victims who suffer from that particular virus.