• Formulating

  Citric acid buffer solution

  Posted by EiraSh on November 26, 2020 at 4:31 am

  Hello, I’m using 1% geogard ultra as persevative in my HA facial serum. I also include 1.5% sodium citrate and 0.2% of 10% citric acid to stabilize ph. My initial ph was 5.76 and I used more 10% citric acid to reduce ph. I wanted it to be around 5. Ph didn’t want to go down (buffer did its job). My question is if I can reduce the % of sodium citrate? so my initial ph will not be as high. Thank you! 

  Ichlas replied 3 years, 4 months ago 2 Members · 4 Replies
• 4 Replies

• 

  Ichlas

  Member

  November 27, 2020 at 4:10 am

  You can use this site: http://clymer.altervista.org/buffers/cit.html for easy citric acid buffer calculation with whatever pH you want

• 

  EiraSh

  Member

  November 27, 2020 at 4:20 am

  Ichlas said:

  You can use this site: http://clymer.altervista.org/buffers/cit.html for easy citric acid buffer calculation with whatever pH you want

  Thank you! 

• 

  EiraSh

  Member

  November 27, 2020 at 12:26 pm

  @Ichlas what would be a buffer capacity in case of emultion? Thank you 

• 

  Ichlas

  Member

  November 30, 2020 at 1:12 am

  EiraSh said:

  @Ichlas what would be a buffer capacity in case of emultion? Thank you 

  It depends on electrolytes present in your system, but 10 mM may be a good start. You also can do trials and pick what is best for you.

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