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Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: MaidenPEI on March 01, 2007, 01:16:28 PM

Title: Storing Colloidal Silver In Plastic Bottles
Post by: MaidenPEI on March 01, 2007, 01:16:28 PM
I make Colloidal Silver at home using distilled water & need to know if it is ok to store the CS in either of these two kinds of plastic bottles 1) the white opaque #2 plastic jugs that the DW comes in & 2) the clear #1 PET plastic beverage/soda/pop bottles or if either of these plastics will react with the silver & degrade or leach into the solution.  Thanx!
Title: Re: Storing Colloidal Silver In Plastic Bottles
Post by: DevaDevil on March 12, 2007, 05:47:10 PM
In my lab we use Nalgene (teflon) bottles to store chemicals (dilute acids, buffer solutions and metal ion solutions) in for up to a 2 weeks without problems. If you want to save them for longer I am unsure whether this would be the material of choice.
Nalgene is a brand name of which also some plastic sports bottles are made. I have no idea what type of plastic the DI water bottle is made from.
Title: Re: Storing Colloidal Silver In Plastic Bottles
Post by: hmx9123 on March 17, 2007, 07:05:02 PM
Be forewarned: Nalgene is a brand name and makes several different kinds of plastics.  The water bottles you see in the store with the Nalgene name on them are not Teflon (I think they're polycarbonate).
Title: Re: Storing Colloidal Silver In Plastic Bottles
Post by: pantone159 on March 17, 2007, 07:41:21 PM
I have Nalgene (TM) brand bottles with the following types labeled:  PC (polycarbonate), HDPE (high density polyethylene), UVPE (not sure), not to mention some IChem brand (part of Nalgene corp) glass vials.  None are teflon.  (I would have noticed that when I saw the price!)

Title: Re: Storing Colloidal Silver In Plastic Bottles
Post by: Sam (NG) on March 23, 2007, 07:13:02 PM
I make Colloidal Silver at home using distilled water & need to know if it is ok to store the CS in either of these two kinds of plastic bottles 1) the white opaque #2 plastic jugs that the DW comes in & 2) the clear #1 PET plastic beverage/soda/pop bottles or if either of these plastics will react with the silver & degrade or leach into the solution.  Thanx!

All plastic containers will interact to some extent with the liquid they are containing.  However, according to this website: http://onlinecolloidalsilver.com/ and several others you can access by typing "colloidal silver PET" or "colloidal silver HDPE" into google sell Colloidal silver in PET and HDPE (Type 2 that you mention above as being opaque) bottles to the general public.

Migration from plastics is much less of a worry with aqueous solutions than with oils etc.  What is the composition of "colloidal silver"? This is the first time i have come across it.
Title: Re: Storing Colloidal Silver In Plastic Bottles
Post by: il bagattel on August 13, 2007, 02:40:47 PM
I found this for the glass vs plastic debate:

Silver in Glass vs. Plastic Containers
by David A. Revelli, MS

Introduction

A great deal of controversy has arisen in the market place on the question of whether it is better to store silver solutions in glass versus plastic containers. There is a misconception that has prevailed in the market place that glass is better. The idea that glass containers are better for storing products which contain silver has never been proven scientifically. In fact, it has been reported in other studies that glass may have a detrimental effect on silver products.

Test Work

I have been conducting biological studies for 3 years, in the laboratory of a major private institution, on the use of silver products to kill and inhibit the growth of bacteria. I have conducted thousands of tests on numerous strains of pathogenic bacteria. In the testing I have completed, I have used both glass (5 ml glass test tubes) and plastic (Falcon 5 ml polypropylene plastic test tubes). In some of the test work we found that there was a difference in the amount of silver that was needed to kill the bacteria when glass was used versus plastic test tubes. In order to make sure this was the case, it was decided that the MIC tests (Minimum Inhibitory Concentration) should be replicated by more than one person and a direct comparison was made. The MIC tests were performed in triplicate in both 5 ml 13X100mm glass test tubes and 5 ml Falcon polypropylene plastic test tubes. Results of the bacterial (MIC) tests showed that Staphylococcus aureus was inhibited at 2.5 ppm when the MIC test was performed in the plastic test tubes. S. aureus was inhibited at 5 ppm when the MIC test was performed in glass test tubes. This suggested that the material with which the test tubes were made, specifically glass or plastic, may have effected the results of the MIC test. Numerous other tests were also completed using larger concentrations of bacterium and in those tests it was found that there was no significant difference at all between using the glass test tubes versus plastic test tubes

Other Studies

The studies which I performed are not the only tests showing that glass, in some circumstances, may have a detrimental effect on silver products. It has been noted in another independent study which has been cited by other researchers that silver can adsorb to glass (Chambers 1960; Thurman 1989). With this in mind, it may have been possible that the silver could have adsorbed to the surface of the glass test tubes reducing the concentration of available silver interacting with the bacteria which resulted in having to use a higher amount of silver to kill the bacteria when the glass test tubes were used.

Conclusion

In the test work I have completed as well as in other available studies, it was found that glass may, in some cases, have a detrimental effect on silver products. While it can be said that glass did not always show the detrimental effect, it can also be stated that we found no problems at all with using the plastic instead of glass. Our tests, in conclusion with the other available independent study (1Chambers et al. and 2Thurman et al.), would suggest, by inference, that silver products should not be stored in glass containers which could reduce the available concentration of silver, but rather in a high quality plastic container.

Respectively,
David A. Revelli, MS

References

Chambers, C. a. C. P. (1960). The Bacteriological and Chemical Behavior of Silver in Low Concentration. Cincinnati, OH, Division of Water Supply and Pollution Control, U.S. Department of Health, Education, and Welfare.

Thurman, R. a. C. G. (1989). "The Molecular Mechanisms of Copper and Silver Ion Disinfection of Bacteria and Viruses." CRC Critical Reviews in Environmental Control 18(4): 295-314.

http://www.lifesilver.com/faq.htm