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Sodium hydroxide

  1. Sep 22, 2011 #1
    If you had a solution of the following

    benzalkonium chloride
    purified water
    sodium chloride
    sodium hydroxide

    what would be the purpose of the sodium hydroxide and would the solution be fine without it?

    What would you use for a safer substitute?
  2. jcsd
  3. Sep 23, 2011 #2
    Sounds like some kind of moisturise aside from it wouldn't be zinc it would be zinc oxide. The sodium hydroxide is there to adjust the pH and I don't see why you'd need a safer substitute, the issue isn't the substance itself it's the concentration which is going to be pretty low.

    Without the sodium hydroxide half the ingredients would probably crash out of solution or separate over time.
  4. Sep 23, 2011 #3
    Its a zinc nasal gel to fight colds. You cant buy it anymore but I found directions on you tube to make it.

    but he says to leave out the sodium hydroxide because he thinks its dangerous. I guess maybe he doesn't know how much to put in to it.

    I made the solution in his video and it came out fine but I would rather put the sodium hydroxide back in if we can figure out a safe amount.

    Any clue to the amount needed for the 2 ounce solution posted above ?

    here is the actual recipe from the video

    1 ounce glycerin water soluble
    1 ounce of walgreens curechrome or cvs mercuroclear (0.12% benzalkonium chloride)
    1/8 teaspoon zinc gluconate
    1/4 teaspoon table salt
    1/4 teaspoon unflavored pure gelatin

    mix all together and microwave for 30 secs
    refrigerate for couple of hours for gel to set.
    Last edited by a moderator: Sep 25, 2014
  5. Sep 23, 2011 #4
    The stability and viscosity of gelatin depend on pH. It would be hard to estimate how much sodium hydroxide you will need without doing a whole bunch of stability and viscosity experiments as a function of pH to find out which combination will give you adequate gel viscosity with acceptable shelf-life for the product. That's one of the trade secrets of the original manufacturer. Granted, the amount has to be a safe amount, but that's only one consideration.
  6. Sep 23, 2011 #5
    I wouldn't care too much about shelf life as I would only make it at the time I needed it and then throw it out a couple of days later after I was convinced that I didn't need it anymore. I mean it took all of 5 minutes to make it besides the sitting in the fridge part.

    So I wonder maybe its fine not to have it if you only make it when needed.
  7. Sep 24, 2011 #6


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    Homework Helper
    Gold Member

    You probably need the pH adjustment to make the gel thick enough to stay in your nose. You will need to determine the amount to add and it isn't dangerous unless you add too much. I'd use pH paper that would let me measure in the range of 7-8. Don't go higher than pH 8 IMO.
  8. Sep 26, 2011 #7
    Surely the advice here should be if you're not absolutely certain you should not be sticking it up your nose?
  9. Sep 26, 2011 #8
    lol.... don't worry, Ill test it on my skin some where before I stick it up my nose. Even then Ill still be extremely careful with a tiny amount before I stick it up my nose which is more sensitive than my skin.

    The PH test strips might be the way to go. I'm in no hurry so I think I will order the stuff and experiment with it. I guess its similar to the pool that we test with the liquid drops to keep the PH under 8 so the swimmers eyes don't burn.

    I just need to order the sodium hydroxide and the PH strips.

    Where do you guys prefer to order from online? Like a place with reasonable prices and a good stock.
  10. Sep 26, 2011 #9


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    Beware - you need a correct purity chemicals. No idea what purity will be OK, nor where to buy them, bust just because someone sells these chemicals doesn't mean they can be used the way you want to use them. There are different classes of purity for different applications, details will depend on where you live.

    I am not convinced you will be safe trying.
  11. Sep 26, 2011 #10
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