Home Cosmetic Science Talk Formulating Chitin suggestions

  • belassi

    Member
    March 26, 2015 at 6:34 am

    I’ve investigated similar botox-like “vege botox” ingredients in the recent past and concluded they were just too eye-wateringly expensive. If they work.

  • Pharma

    Member
    March 26, 2015 at 12:36 pm

    Unmodified chitin is a non-charged polymer and not water soluble but could be used as a suspension should you want a scrub or certain visual effects.
    Chitosan is the simplest water-soluble derivative but requires to use a precise amount of an acid to bring it into a proper solution. Though, you can buy readily soluble salts such as chitosan HCl. It’s a high viscosity thickener and film-builder. Alternatively, chitosan oligosaccharide (usually as lactate salt) is low viscosity and a lot more expensive too but probably partially bioavailable and the most active form in in vitro tests.
    These are cationic polymers (arguably the only natural cationic polymer) and behave differently than the more common anionic ones. They tolerate for example calcium but will drastically increase in viscosity (and finally floculate/precipitate) when mixed with polyacids (e.g. citrate, glutamate, phytate). The two modifications you listed are anionic and water soluble derivatives which are, regarding handling and preparation, similar to polyacrylates (carbopol) where you add a base to neutralise and dissolve them (unless, again, you directly purchase the salt form). I’m not familiar with these anionic derivatives but can tell you that chitosans aren’t just that: every product is different due their inhomogeneous composition and you have to look at the manufacturers specifications (like degree of polymerisation and degree of deacetylation). This is likely true for your examples.

  • beautynerd

    Member
    March 26, 2015 at 7:30 pm

    @Belassi… price is always the clincher. dangit. 

    @Pharma… let’s suppose chitosan oligosaccharide were in my budget (remains to be seen); does that mean using phytic acid as the formula’s chelator will likely destabilize things? 
    Prior to looking down the chitin rabbit hole, the facial mask was a simple o/w emulsion with clay as the thickener (to be consistent with our product line/everything needs to be clay based) and niacinamide as the “active” with a final pH of 5.8.
  • Pharma

    Member
    March 26, 2015 at 9:01 pm

    Not necessarily. Though by definition up to 20, the chitosan oligosaccharides I’ve came across have only between 2 and 10 monomers. This means that they don’t tend too strongly to coagulation and viscosity shouldn’t be increased too much either. It all depends on the relative amounts of chitosan (more precisely the amount of deacetylated monomers) versus phytate. If all goes well, I should receive some phytic acid somewhen around Easter, I’ll try it out (wanted to do that anyway) and keep you posted. Do you have a specific concentration for either of the two in mind?

    Besides, pH 5.8 would be perfect for chitosan!
    On the other hand, which clay do you use? I’m not really interested in the name or mineral per se, just the CEC (cation-exchange capacity) ;) . Most clays have a negative surface charge and hence will behave much like phytic acid. Being rather huge particles, chitosan oligomers will simply stick to their surface, coating them in a molecular film of opposite charge (does zeta potential mean anything to you?). Depending again on proportions, this will affect rheology. Should you use high molecular weight  chitosan, then the effects will be even stronger… may be good, may be bad. Honestly, as exciting/funny/promising all this may sound, it all looks pretty much like a possible problem you could easily avoid by using the anionic modified chitin derivatives you first mentioned (should they be soluble at pH 5.8).
    Just remembered: I have montmorillonite around and given the proper motivation… :)

  • beautynerd

    Member
    March 26, 2015 at 11:28 pm
    Vit B3 @ 6%, Phytic Acid 1%

    The clay/silt is from a sediment rich glacial stream, harvested from the shore by the hands of yours truly; we’re in the far far far Northwest corner of Canada. We heat and hold it for several hours then sift to less than 150 microns although most of it is smaller than 63.

    I get the mineral content is not so helpful but for the sake of full disclosure, the XRD analysis came back as:
    Quartz 32.4%, Muscovite 11.4%, Albite 14.0%, Calcite 14.1%, Dolomite 13.0%, Clinochlore 9.1%, Ankerite 2.5%, Orthoclase 3.5%
    Zeta potential? Hmmm. Will have to google that one. Okay, so out of curiosity, how would one attempt to measure the CEC? 
  • beautynerd

    Member
    March 27, 2015 at 2:51 am

    Ok… did some reading. 

    Looks like CEC of any of these minerals is likely to be of little significance regardless of pH or grain size. 
    Note we refer to this as “clay” in the loosest of terms. So chitosan with this thickener should be good right?
    BTW… the right motivation? my status as a laywoman? for shame. 

    ;;)

  • Pharma

    Member
    March 27, 2015 at 11:00 am

    Interesting! Thanks for sharing!

    That’s a lot of phytic acid; it will likely ‘overpower’ the chitosan molecules and reduce their gelling efficacy and avoid cross-linking but that remains to be tested. How much chitosan would you want to include anyway?

    Does your clay help with stability (except making things thicker), like thixotropy as seen with bentonite? If not, then that’s a good sign that it could tolerate chitosan quite well. A low CEC means that just a little chitosan could neutralise the surface charge and completely change the physical/rheological behaviour of those particles.

    The zeta potential is a measure to predict stability of emulsions and suspensions based on their surface charge. I usually use magnets to explain it but as we’re already into the dirty talk (I honestly wasn’t thinking what you’re thinking but now that you mention it ROFLMAO): Imagine you were in a bar with only women, all heterosexual. The more hetero you are, the more you will repel each other and there less cuddling (aggregation) or even *cough-cough* (coalescence) there will be, the room will remain in order, the atmosphere stable. If you now add some chippendales (opposite charge) all hell will break loose…
    In case of non-ionic particles or surfactants (-> PEGs) it’s more like you being in a lesbian bar: The more and longer arms and legs you have and the wilder you wiggle them around, the higher your chances of keeping the hot chicks off of your skin. I hope you get the point :) .

    Bottom line is: I suppose there’s no other way than to try.

  • Bobzchemist

    Member
    March 27, 2015 at 2:56 pm

    @Pharma, I love your explanations!

  • Pharma

    Member
    March 27, 2015 at 7:51 pm

    @Bob Thanks for the flowers <3
    Although, I’m usually quite serious and… (add pretext and other excuses HERE)

  • beautynerd

    Member
    March 27, 2015 at 9:25 pm

    @Pharma: Lol…. salacious but I much prefer that visual to the magnets.

    Sinerga is sending a sample of their chitoglycan (carboxymethyl chitosan) my way. 
    So it’s back to trial and error with my new found knowledge. 
    Thanks for the insight. I’ll let you know what happens.
  • Pharma

    Member
    March 27, 2015 at 9:54 pm

    Cool!
    Good luck and I’m looking forward to whatever you learn!

  • beautynerd

    Member
    April 14, 2015 at 6:24 pm

    @Belassi … Eye-watering. You weren’t kidding! A Canadian company just quoted $1,080 USD for 50 g of N-trimethyl chitosan (100%).

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