Often times adding clays or powders to lotions may make them harder to sterilize. I suggest you sterilize the powder or pigment before adding them you formations that contain water. It is quite simple and straightforward. copyright diycosmetics.com 2017
Ref: Martindale Pharmacopoeia
- Completely remove all moisture from the powder by putting it into at over on low heat (100 degree C). Do this for about 15 minutes.
- Bake the powder at 160 degrees C for at least one hour.
- Decant into an sterile container till ready to use.
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So simple and so effective!
Absolutely will NOT sterilize
Thank you for your comment Phil. I have used this method for years and did make a change because F is in error it should be Centigrade Temperature. I first found this method outlined in Martindate British Pharmacopoeia so assume it is correct but I have never gone the next step to test it in a aqueous solution. You would know better on that point. Rebecca
Thanks. The 160C must be for at minimum two hours ( https://www.cdc.gov/infectioncontrol/pdf/guidelines/disinfection-guidelines.pdf ) and must ensure complete exposure throughout the material to that temperature – not just being in an oven set at that temperature.
Thank you, I will have a read.
Rebecca