How do emulsifiers work?

SaltyNuts

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May 1, 2001
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Let's say I've left some St. Johns Wort leaves in some olive oil so infuse the olive oil with the St. John's leaves active ingredient or ingredients, whatever that or those may be. And let's assume that it worked (I am just making this up as an example). I could now apply the oil to my skin and hopefully get some of the St. John's stuff to absorb into my skin and what not.

But let's say I didn't want nasty oil on my skin, I instead wanted to apply it is a water like liquid. I couldn't just add water to the oil, they don't mix. But could I add water to the oil, add some emulsifiers, mix well, then run the water through a strainer to strain off whatever big stuff is left behind, leaving the water infused with St. John's Wort? Is that how it works? Or how do the emulsifiers otherwise work?

Thank you!
 

biostud

Lifer
Feb 27, 2003
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So how would we be able to explain something like this better to you than youtube?

 

SaltyNuts

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Thank you biostud. I have watched videos and read about them. But I was more hoping for help on my particular question - would they work in that context to keep the St John's active ingredient in the watery mixture after you mix the water with the oil and emulsifier. Thanks.
 

sdifox

No Lifer
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Thank you biostud. I have watched videos and read about them. But I was more hoping for help on my particular question - would they work in that context to keep the St John's active ingredient in the watery mixture after you mix the water with the oil and emulsifier. Thanks.

No.
 

biostud

Lifer
Feb 27, 2003
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You would have to know the chemical properties of the active ingredients. While they might not be water soluble they might be be soluble in alcohol, but at this point you should probably rather buy a professional made product with the properties you're looking for.
 

SaltyNuts

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You would have to know the chemical properties of the active ingredients. While they might not be water soluble they might be be soluble in alcohol, but at this point you should probably rather buy a professional made product with the properties you're looking for.


Thanks biostud! But let me ask you this. Let's say St John active ingredient is soluble in oil, but not water. If the emulsifier brings the oil and water together so it is a single liquid, would not at least some portion of that active ingredient, corresponding to the oil portion, remain in the solution? I.E. if you mix 60% oil and 40% water, and use an emulsifier, won't the resulting solution have 60% of the active ingredient per portion as had the oil originally?

Thanks!!!
 

sdifox

No Lifer
Sep 30, 2005
95,030
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Thanks biostud! But let me ask you this. Let's say St John active ingredient is soluble in oil, but not water. If the emulsifier brings the oil and water together so it is a single liquid, would not at least some portion of that active ingredient, corresponding to the oil portion, remain in the solution? I.E. if you mix 60% oil and 40% water, and use an emulsifier, won't the resulting solution have 60% of the active ingredient per portion as had the oil originally?

Thanks!!!


If it is not soluble in water how will it transfer from oil to water?
 

WelshBloke

Lifer
Jan 12, 2005
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Thanks biostud! But let me ask you this. Let's say St John active ingredient is soluble in oil, but not water. If the emulsifier brings the oil and water together so it is a single liquid, would not at least some portion of that active ingredient, corresponding to the oil portion, remain in the solution? I.E. if you mix 60% oil and 40% water, and use an emulsifier, won't the resulting solution have 60% of the active ingredient per portion as had the oil originally?

Thanks!!!
No. If the active ingredient is soluble in oil it'll be held in the tiny droplets of oil in the emulsion.
The oil in an emulsion is just tiny droplets held in a stable (ish) suspension in the water.
 
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biostud

Lifer
Feb 27, 2003
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No. If the active ingredient is soluble in oil it'll be held in the tiny droplets of oil in the emulsion.
The oil in an emulsion is just tiny droplets held in a stable (ish) suspension in the water.
This

You would need some way to separate the oil and active ingredients, typically chemical solution like alcohol or another organic solvent.
 

Paperdoc

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Aug 17, 2006
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WelshBloke and others have it right.

Oil (olive or others) and water do not mix, as you say. What an emulsifier does is coat microscopic droplets of oil in a layer of emulsifier molecules that have little "water-loving" ends sticking out. So EACH individual droplet can mix with the water and STAY suspended in the water (without settling in a separate layer) for a longer time - say, days, rather than seconds).

We assume that the unidentified magic ingredients of the St. Johns Wort are soluble in OIL, and not water - VERY likely - so your original infusion has those molecules truly dissolved in the olive oil. You did that because they would NOT dissolve in water to start with. If you then add an emulsifier and agitate to break up all the oil into emulsified droplets, the St Johs Wort items are still in the oil droplets. They will STAY that way - they have a strong affinity for oil, and no affinity for water. They will NOT migrate from the oil into the water. So, even if you could then de-stabilize the oil droplets and get them into a layer you could separate from the water, the St Johns Wort items would still be in the oil.

For commecrial preparations like this, they use very particular emulsifiers - you have to know exatly what and how much - to make an emulsion of oil containing the desired molecules from the original source, emulsifed in water to make a fluid mix that may look slightly or very cloudy. Then they sell that entire mixture. If it is intended for topical application, you smooth it on and the water starts to evaporate. SOME water and SOME oil may penetrate into the skin carrying the extracted molecules with the oil. But some oil will remain on the surface and be washed off later. Hard to say how much of the original materials you wanted (e.g., from St Johns Wort) actually get through the skin into your body.
 

WelshBloke

Lifer
Jan 12, 2005
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Well shit, that is a big bummer. I follow however. Thanks everyone. :(
It shouldn't be an issue really. Most stuff isn't going to get through your skin regardless of whether it's dissolved in oil or water. There are some funky chemicals that'll help stuff get through but you don't want to be messing with stuff like dissolving things in DMSO.

What are you trying, specifically, to make a tropical preparation of?
 

SaltyNuts

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May 1, 2001
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Its kind of a secret WelshBloke. I'm working on something I am going to sell. It is going to be big time when I launch it. Sorry I cannot disclose. :( Thanks again for the help!