Home Cosmetic Science Talk Formulating Skin Formulating a clear serum with max 10% oils

  • Formulating a clear serum with max 10% oils

    Posted by rosa on September 28, 2021 at 8:33 pm
    Hi,
    I would like some advice on formulating a serum that has some oils in it. I have made serum using polysorbate 80, but the emulsion is always turning white.
    How do people incorporate oils and still have clear serums?
    Rosa
    suswang8 replied 3 years, 2 months ago 4 Members · 5 Replies
  • 5 Replies
  • Paprik

    Member
    September 28, 2021 at 11:25 pm

    Do I understand correctly you want to have an emulsifier free serum with 10% lipids?
    You need to realise that around 10% lipid is being used it normal lotion/cream formulas. 

    To solubilise 10% of a lipid you would need (depending on the type of oil etc..) around 50% of solubiliser. As usually it takes 5:1 ratio. Sometimes even 10:1. (1:1 if you are lucky). So imagine it in a formula. 

    Usually more than 5% of solubiliser feels sticky on the skin. 

    So if you lower the oils (all oils - including antioxidant, fragrance etc) to a normal level, you need to solubilise it first in P-80. Basically mix those two properly (micelles are formed) and then, in small amounts add that solubilised lipid into the water phase and wait everytime until solution clears. Some might not finish as crystal clear at all tho. 

    Hope that helps.

  • rosa

    Member
    September 29, 2021 at 2:39 pm
    Hi Patrick and thanks.
    No, I understand I need a emulsifier, but I do not want a whitish final product which has always been the case with P 80?
    Is 5% oils better, so for 5% oils, I would start with 2.5% P80? And that should clear?
  • Pattsi

    Member
    September 29, 2021 at 2:52 pm

    Paprik said:

     As usually it takes 5:1 ratio. Sometimes even 10:1. (1:1 if you are lucky)

    as @Paprik mentioned - usually solubilizer 5 : oil 1

    So you may start with P80 5% and oil 1 %.

  • Paprik

    Member
    September 29, 2021 at 6:06 pm

    @Pattsi, what she said.

    What is actually happening is, every drop of an oil is being “surrounded” by the solubiliser. It’s called a micelle. So you can imagine need much more solubiliser than oil. 

    Some oils are harder to solubilise, some are easier. That is why we can’t give you the exact amount of solubiliser you will need. 

    Don’t forget, the method is crucial. 

  • suswang8

    Member
    September 30, 2021 at 1:35 am
    Hi, Rosa.
    I’m not sure if I understand your goals, but you can try something like Ecogel or sclerotium gum (Amigum).  Both can accommodate up to 10% oils, I believe.  Ecogel is regarded as an emulsifier, but Amigum creates a suspension, from what I understand.  Another route is something like SymbioSolv, but that is a solubolizer (not an emulsifier).

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