Home Cosmetic Science Talk Formulating Advanced Questions Raising pH with L-Arginine

  • Raising pH with L-Arginine

    Posted by Bluebasil on June 15, 2023 at 2:19 pm

    Wondering if anyone has any idea of what happened.
    I need to dissolve an ingredient in water at pH 9.5-10.5, so I raised the pH of distilled water with L-Arginine to 10.14. Covered it and came back in the afternoon took pH reading and it was 9.74. Calibrated the pH meter, just in case.
    Came back the next day and took reading 9.35, so I added more L-Arginine, pH now at 9.75, came back the next day, took reading = 9.28.
    Anyone has any idea why? Should I use something different to raise pH?
    Any comments appreciated.

    Graillotion replied 1 year, 4 months ago 5 Members · 7 Replies
  • 7 Replies
  • Adamnfineman

    Member
    June 16, 2023 at 11:10 am

    Have you tried replicating this with other bases? I’d say make a larger batch then split it and try raising the pH with TEA, NaOH, or whatever else you might have on hand.

    • Bluebasil

      Member
      June 16, 2023 at 3:23 pm

      Thank you for the suggestion. I will try.

      • fareloz

        Member
        June 21, 2023 at 6:10 am

        What are your results? It’s very interesting to hear

        • Bluebasil

          Member
          June 30, 2023 at 4:52 pm

          Hi, I tried again raising ph (was trying to raise pH to 9.5) with NaOH and something similar happened. I would raise pH, get reading with pH meter, then next day I would come back, measure again and I would get a different reading. Didn’t know what to make of it, so I used pH strips just to see what reading I would get. The strips coincided with the reading that I would get after some time had passed.
          I am thinking that what was happening is that my pH meter wasnt giving me a correct reading because it was calibrated with 4.01 and 7.01 solutions. Never with a 10.1 solution. So when I tried to measure a higher pH than 7, it wasn’t giving me a correct reading. That is the only thing I can think of. Either way, I am getting a new pH meter, and calibrating with 4, 7, & 10 and Im hoping that will solve the issue.
          I will report back if I see something different.

          • fareloz

            Member
            July 6, 2023 at 8:24 am

            Hi! Thank you for the response, I am very curious of how this “detective” story ends))

  • MarkBroussard

    Member
    July 1, 2023 at 10:40 am

    @Bluebasil

    Perhaps the ingredient you are trying to dissolve effects a downward pH drift.

  • Graillotion

    Member
    July 6, 2023 at 3:26 pm

    How long has it been, since the probe on the meter has been replaced?

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