Ascorbic acid in silicon-free suspension


We are looking to develop a silicon-free anhydrous suspension with ascorbic acid. Silicon-free due to market trends, although we know silicons are not that bad and actually fine.

We use an ultra fine Ascorbic acid powder so that no actually solubilisation is necessary. We were thinking of using either:

- Zemea (Propanediol)
- Ecosilk (Isoamyl Laurate & Isoamyl Cocoate)

We know technically we could dissolve ascorbic acid in Zemea, yet we want to be able to achieve a higher concentration of Ascorbic acid in the final formulation.

So the question is; do any of you have any ideas on how we could thicken / suspend either of the above two ingredients, so that we can suspend Ascorbic acid powder in the formulation?

Any other suggestions also welcome of course! We do want to stick with ascorbic acid and don't want to use Vit C derivatives.

Thanks a lot in advance!


  • Or alternatively, we could combine a silicon alternative (ecosilk) with Zemea.

    " Due to the instability of Vit C when in contact with water, new strategies and also new formulations are being proposed for the dissolution of the active. Appropriate solvents such as glycol to form one phase, appropriate oil phase such as silicone oil or another oil with a light feel. The Vit C is soluble in polyol solvents, such as propylene glycol, butylene glycol, hexylene glycol, glycerin, polyethylene glycols, glycereth-7, glycereth-26, ethoxydiglycol and ethanol. The advantages of using any of these solvents for nonaqueous emulsions are that they have less oxygen permeability and do not carry water, which prevent discoloration reactions in the formulation. These polyol solvents, appropriate oil phase and surfactants combined together, can form two immiscible phases which result in a nonaqueous or anhydrous emulsion that are heat-stable, non discoloring and also able to deliver the active.20"

  • Just not sure how to achieve that
  • Bill_TogeBill_Toge Member, Professional Chemist
    ascorbic acid will dissolve in alcohols and short-chain glycols, which makes it less susceptible to oxidation; it's not as soluble in those solvents as it is in water
    UK based formulation chemist. Strongest subjects: hair styling, hair bleaches, hair dyes (oxidative and non-oxidative) I know some stuff about: EU regulations, emulsions (O/W and W/O), toothpaste, mouthwash, shampoos, other toiletries
  • Thanks! we are not really looking to dissolve it, rather to produce something similar to say the Ordinary Ascorbic acid suspension in silicon which is kind of gritty and therefore not dissolved. Yet we would prefer to use silicons and would want to thicken a silicon alternative (for instance).
  • EVchemEVchem Member
    off the top of my head:

    For thickening glycols
    -Silica (aerosil 200)
    -Polyglyceryl-10 Tristearate (Bar Gel G from Barnet)
    -Polyacrylate Crosspolymer-6 (Sepimax Zen, I haven't tried this one but heard it can slowly hydrate in glycols)

    If you go the oil route you will have to match the oil gellants to the polarity of your chosen oils (the oilkemia series worked okay for me). There are several discussions on the forum about oil gelling that are worth looking into.
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