[MarkBroussard]

Unless the undefined “water soluble plant extract” is licorice root extract or daisy blossom extract or some other skin whitening extract.

[MarkBroussard]

Well, if you leave out the MgAscorbylPhosphate, Niacinamide and Kojic Acid … then your formulation is not going to be a skin whitening cream … it will essentially be a very weak glycolic acid exfoliating cream since the glycolic will be most effective at pH 3.5.

As mentioned above … did you use the HLB system?  If not, you probably should to get the proper ratios of emulsifiers/oils.

Frankly, I would leave out the cyclopentasiloxane and the glycolic acid/NaOH.  MgAscPhosphate will be most stable at pH 7.0 and Niacinamide at 6.0.  So, if your objective is to form a skin whitening cream, best you formulate to the pH where the skin whitening actives are most stable.  As it is, you’re trying to bridge the pH gap between the glycolic acid and the vitamins and getting the worst of both worlds.

[MarkBroussard]

Well, the simplest solution when you see a post where it is apparent that the poster has not first bothered to do their homework is to just not provide any information. You can’t stop anyone from asking, but you certainly can stop yourself from answering.

[MarkBroussard]

Yes, Urea can be a skin irritant at high concentrations, but at anything less than 5% should not be a problem

[MarkBroussard]

I have not tried mixing it that way, but it is an interesting article, which I skimmed, but did not read thoroughly … yet.

I recall from my experiements with it that Konjac will gel with Xanthan or Hydroxyethylcellulose, but forms an inconsistent glob with Sclerotium Gum.

Give it as shot.  The gist of the article would seem to indicate that you are correct in mixing the two above 90C and it forms a stable gel upon cooling.

[MarkBroussard]

Silverson L4RT is an excellent mixer … Built like a tank … They last forever. You might look into the new version, the LT5 … It’s on their website and runs $5,000 US brand new. Many used LT4’s can be in pretty rough condition relative to the asking price.

[MarkBroussard]

Find an analytical chemical testing lab in your local area.  They should be able to help you with that.  Send them the LOI and samples of the products.  They can test the samples against standards of the ingredients on the LOI and tell you if those chemical compounds are in the sample.

Is your concern that some of the listed ingredients are not in the product at all … meaning the LOI lists ingredients that are not actually in the product.  

Or, is your concern that compounds other than what is listed on the LOI are in the product? These two scenarios will help the lab in the analysis.

This might be an expensive undertaking.  Have you requested that the supplier of the product supply to you a certificate of analysis?  That might be your best first pass at figuring this out without you having to pay for the analysis.

[MarkBroussard]

@Zink:

You might contact IrinaTudor who is the resident expert on fragrances/scents on this forum.  She may have some ideas/suggestions for you.

[MarkBroussard]

It really depends on what scent you’re trying to mask? Perhaps best to try to compliment that scent as opposed to overpowering it.

[MarkBroussard]

Well, as a general guideline, approximately 15% oil in an O/W emulsion is about the right amount.  Check the formulation guidelines for the emulsifiers that you plan on using.  And, do an HLB calculation to determine the proper percentages of each of the respective emulsifiers for the combination of oils you are planning to use.

Other than that, as stated above, you need to experiment.

[MarkBroussard]

Ooops!  Just noticed this thread.

Yes, I would certainly try Konjac Root Powder as a thickener.  You might also try NaCl as your cheapest option with a readily available ingredient or a combination of the two.

[MarkBroussard]

Well, I’ve found that is generally is most stable at a pH between 3.5 and 4.0.  But, you simply dissolve the SA in whatever alcohol you’re using and run experiments to figure out the alcohol/water ratio that keeps the SA in solution.  You’ll generally need at least 20% alcohol, perhaps closer to 30%.

What I do is make a stock solution of 10% SA in alcohol and slowly add this stock solution to water to get the concentration of SA that I am targeting … usually in the 1% to 2% range.

You can also eliminate this by using an encapsulated SA or natural salicylate extracts that are water soluble, but they are substantially more expensive than Salicylic Acid.

[MarkBroussard]

Olivem 1000 generally is required at 6% to 8% to form stable emulsions in creams, but although it is advertised as a stand alone emulsifier, that really is not the case in actual practice.

For Creams:

Olivem 1000  6%

Glyceryl Stearate  2%

Cetyl Alcohol 2%

Xanthan Gum 0.2%

For Lotions:

Olivem 1000  3%

Glyceryl Stearate 2%

Cetyl Alcohol 1%

Xanthan Gum 0.2%

[MarkBroussard]

@EliseCortez:

Thanks for your e-mail referencing the Dermascope article.  There is only one line in the article regarding Salicylic Acid and emollients and give no detailed explanation as to the rationale for her comment regarding SA and emollients.  I am unaware of any incompatibility between the two.  Personally, I would not put too much stock in that statement.

From what I gather, the author is referring to the use of AHA’s and BHA as exfolliants in chemical peels.  For instance, she referred to using AHA’s at 30% which is in the chemical peel range.

[MarkBroussard]

Yes, http://www.kinetiktech.com

[MarkBroussard]

Part of the improvement in acne in hanging out at the beach is that the sun exposure stimulates Vitamin D production which reduces sebum production.  That, and the salinity of the water most likely kills off the P. Acnes population.

I would think the most effective “synthetic seawater” would be in the form of a gel or mask.

In addition, the pH between 7 and 8 is similar to disincrustation fluids used by estheticians to “melt” the waxy sebum buildup around blackheads to aid in extraction of comedomes.

[MarkBroussard]

Well, it’s a bit more complex than just soaking in salt water.  Besides the salinity, you have a mix of minerals in sea water, the pH, and dissolved gases, the major components comprising 99% of the chemical composition of seawater being:

Hydrogen H2O 
Oxygen H2O 
Sodium NaCl 
Chlorine NaCl 
Magnesium Mg 
Sulfur S 
Potassium K 
Calcium Ca 

Note that Sulfur is an approved OTC ingredient for acne.  Seawater typically has a pH of 7.3 to 8.5.

It should be quite easy to formulate a “synthetic seawater” and test it.

[MarkBroussard]

Can you provide a link to the article or more specific information.  Hard to answer your question based on this limited information.

If you want to make a gel-only mask, try using Konjac Root Powder as your gelling agent.

[MarkBroussard]

Anytime, Galina.  It’s a really nice ingredient!

[MarkBroussard]

@Belassi:

If it’s a shipping problem, then it’s a preservative problem.  Bob said that he had the supplier send a sample from the supplier’s location to Bob’s lab … that sample also failed the test at Bob’s lab.

If the material cannot withstand shipping extremes, then it is likely that the preservative is inactivated during transport.

@Bob:

I am assuming from your comments that you have been purchasing this same product from this supplier for some time now.  Something obviously has changed in the past couple of months … prior to, I am assuming that the supplier’s product had a history of passing at your lab?

So, the question is:  What has changed, if anything on the supplier’s side … change in manufacturing, preservative, etc.  If nothing has changed supplier-side, then the problem has to be with one of the two labs.

[MarkBroussard]

Well, it seems there is a problem with one of the two labs.

I would suggest you have your supplier pull two samples prior to shipment and send one to his usual lab and the second sample to a completely different lab that neither of your organizations use, but a mutually-agreed upon lab.

You, Bob, might do the same on your end.  Upon receipt, pull two samples and send one to your usual lab and a second to a completely different lab.

That way, you might be able to nail down which lab has a QA problem … yours or your suppliers.’

[MarkBroussard]

@BobZ:

Have each of these labs produced reliable results for you in the past, or is one of them a new lab to your organization?

Perhaps your sample got mislabeled at one of the labs is the only thing I can think of since they would both be following the same testing protocol.

Do you know what the contaminating organism was in the test that failed?  

[MarkBroussard]

Here’s a published article relevant to this discussion:

http://www.nature.com/jid/journal/v113/n5/full/5600510a.html

[MarkBroussard]

Have you tried Camel Urine?

[MarkBroussard]

With Optiphen Plus you really should not have to worry about adverse skin reactions even though it contains Sorbic Acid.  I use it a maximum concentration and have never had an issue.