Home Cosmetic Science Talk Formulating Citric Acid For Chelation

  • Citric Acid For Chelation

    Posted by thebrain on May 18, 2015 at 11:35 pm

    I’m trying to find an alternative to EDTA for shampoo. Can I use citric acid?

    Chemist77 replied 9 years ago 4 Members · 15 Replies
  • 15 Replies
  • MarkBroussard

    Member
    May 20, 2015 at 12:34 am

    @thebrain

    Yes, you can use Citric Acid.  Probably better is a combination of Citric Acid and Tetrasodium Glutamate Diacetate (Dissolvine GL-47).

  • Chemist77

    Member
    May 20, 2015 at 1:18 am

    @MarkBroussard Do they work individually or inclusion of citric acid provides a better environment for Dissolvine functioning? I have Dissolvine NA and NA2, do you think the acid will help here as well??? Last but not the least, can citric acid be used across the board with dissolvine or it will depend on formula type e.g. ok for a shampoo or dishwash but not for a cream or lotion or any similar emulsion??

  • thebrain

    Member
    May 20, 2015 at 2:21 am

    @MarkBroussard

    May I ask why you suggest using another chelator with citric acid? Is there a synergy by using more than one? I already use 0.4-0.5% citric acid to adjust the pH to ~5.0. I added EDTA because it didn’t occur to me that citric acid was already chelating for me, and I wanted something to boost the efficiency of my “natural” preservative. I’d like to drop the EDTA because my customers don’t like it (I’ve already made my case that it’s safe).

    Thanks for your help.

  • MarkBroussard

    Member
    May 20, 2015 at 12:04 pm

    @thebrain @chemist77

    Both Citric Acid and Dissolvine work individually, but Dissolvine is a more effective chleator than either Citric Acid or EDTA. 

    The reason I recommended using both is that there is a synergistic effect between Citric Acid and Dissolvine that besides providing Chelation, really boosts Preservative efficacy.

    So, you have a multifunctional effect … Citric Acid acidifies (pH) adjuster, chelates and provides some preservation properties, Dissolvine chelates and the combination can double the efficacy of certain preservatives like Gluconolactone/Benzoic Acid.

    I use the combination in virtually every one of my formulations and have never had a problem regardless of the format, except for formulations containing Sodium Ascorbyl Phosphate … standard ingredients for me.

  • thebrain

    Member
    May 20, 2015 at 12:59 pm

    @MarkBroussard

    Thank you for explaining. One last question: Do you know of any research or other data source that compares chelators? I’ve been able to look up these chemicals individually, but I haven’t been able to find a comparison. It’s hard to make a decision on which chemicals to use if there is no benchmark comparison.

  • MarkBroussard

    Member
    May 20, 2015 at 4:31 pm

    @thebrain:

    Nothing that specific, just information I picked up from various sources.

  • Chemist77

    Member
    May 21, 2015 at 1:14 am

    Thanks @MarkBroussard.

  • ozgirl

    Member
    May 21, 2015 at 1:55 am

    @thebrain

    Here is a technical brochure that compares the sequestering values of Dissolvine GL with EDTA and NTA (page 7)

    http://www.subsport.eu/wp-content/uploads/2012/05/AkzoNobel_Gl_Technical_brochure_tcm108-40030.pdf

    Hope this is useful.

  • thebrain

    Member
    May 22, 2015 at 8:51 pm

    I’d like to try GLDA, but it doesn’t look like it’s sold at any e-tailers (e.g. lotioncrafter, theherbarie, etc.). Cosmetic chemistry is still a hobby of mine, so I’m only buying in tiny quantities. Does anyone know where I can get some?

    If GLDA is a no-go, can anyone comment on the efficacy of these chelators, in comparison to GLDA and/or EDTA:

    • Phytic acid
    • Glucono delta-lactone (GDL)
    • Trisodium Ethylenediamine disuccinate

    The last two are the easiest to get. I’d have to buy in bulk off of ebay for the phytic acid.

    Thanks for helping @MarkBroussard and @ozgirl.

  • MarkBroussard

    Member
    May 22, 2015 at 11:26 pm

    @thebrain:

    Trisodium Ethylenediamine Disuccinate works just fine. 

    Gluconolactone is a good adjunct to a preservative and has good skin properties. 

    Phytic Acid … really don’t use it.

    If those are your three options, I would go with the TED.

  • Chemist77

    Member
    May 28, 2015 at 8:13 pm

    @MarkBroussard I am using Dissolvine GL38 in my balsam conditioner (rinse off), but the only downside I feel is that it takes pH too high and then again I need lot of citric acid to bring it below 5. Now my point is the efficacy of the chelant at that pH because generally most of the chelants have very high pH as such.

  • MarkBroussard

    Member
    May 29, 2015 at 7:10 pm

    @Chemist77

    Curious, have you measured the pH of GL38 in water?

  • Chemist77

    Member
    May 30, 2015 at 1:04 am

    I have the specs and the pH is mentioned between 10-11 (although need to check if it is as is or 1% solution) but I do have noticed a jump in pH after the addition and then I generally use citric acid to bring it down. But my point is again the efficacy of the chelant at such acidic pH of 4-5.

  • MarkBroussard

    Member
    May 30, 2015 at 2:01 am

    I’m certain I have come across some technical papers regarding chelating efficacy at various pH levels.  I do not recall reading anything indicating substantially reduced performance at lower pH levels, but it’s a good line of inquiry for further research.

  • Chemist77

    Member
    May 30, 2015 at 4:52 am

    It’s just a wild thought that crossed the mind.

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