Home Cosmetic Science Talk Formulating Buffering Question

  • Buffering Question

    Posted by DavidW on October 19, 2016 at 2:37 pm

    I am working on samples for a client of various skin peels using different acids.  Some are glycolic, salicylic, lactic, mandelic.  Not all in the same product but some have more than one acid.  Over time the pH of some of the products are drifting downward.  Does anyone have experience with buffering these types of products?  Thanks.

    Iaskedbetter replied 7 years, 6 months ago 3 Members · 4 Replies
  • 4 Replies
  • chickenskin

    Member
    October 19, 2016 at 10:22 pm

    might try a combo of Citric acid and NaOH 50% soln. raise it up then get it into the 6.5pH range

  • DavidW

    Member
    October 19, 2016 at 11:11 pm

    But it’s a peel.  The final pH is around 2.7 to 3.2

  • chickenskin

    Member
    October 22, 2016 at 5:34 am

    @DavidW oh gotcha well just lower it with citric then raise it to 3.0 with NaOH

  • Iaskedbetter

    Member
    October 28, 2016 at 5:48 pm

    That might work but you’re better off using an actual buffer system (acid + conjugate base). Use a buffer table (citric acid + sodium citrate). Otherwise a phosphate-citrate buffer should work in that range.

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