Niacinamide pH stability - Chemists Corner

Formulating

Niacinamide pH stability

Posted by SandalwoodBreeze on May 13, 2018 at 5:04 pm

I’ve seen a lot of conflicting information about the pH stability of Niacinamide. Some sources say it can tolerate pH as low as 3 and others say not to go under pH 6. Do any of you have any experience working with Niacinamide or know what the lowest pH it can tolerate before converting to Nicotinic Acid. I’d like to include it in a formula with glycolic and lactic acid.

Doreen replied 6 years ago 4 Members · 9 Replies
9 Replies

Doreen

Member
May 15, 2018 at 8:39 am

I think a lower pH might accelerate niacinamide hydrolysis, I keep it above pH 4 (just like panthenol). I agree that some sources can be contradictive.
I saw that Paula Begoun from Paula’s Choice uses a lot of actives in acidic products like her exfoliating BHA/AHA toners. Tip: read the ingredients lists of these toners, they all have a pH of between 3.2 to 3.8.
Doreen

Member
May 15, 2018 at 8:42 am

I have found an article that might be interesting for you.
Microformulation

Member
May 15, 2018 at 9:59 am

In their documentation they recommend; “A pH value of 5 - 7.5 is required to avoid hydrolysis and free acid formation, best stability at pH 7.”
https://www.ulprospector.com/documents/1556314.pdf?bs=613&b=748034&st=1&r=na&ind=personalcare
Doreen

Member
May 15, 2018 at 10:32 am

@Microformulation
Ok, thanks! I will keep that in mind next time that I use it!
Microformulation

Member
May 15, 2018 at 11:32 am

Also, @CedarWind108, unless you have significant experience, don’t attempt an AHA product. For example, do you know what the max AHA percentage and the lowest recommended pH for an at home product per the CIR standards are? What must you include on the labeling? These are all valid questions you must look into.
SandalwoodBreeze

Member
May 17, 2018 at 3:40 pm

Thanks @Doreen! If a big brand like Paula’s Choice is using it without problems and complaints I’d assume it’s pretty unlikely to convert to Nicotine Acid at a reasonable pH or the Nicotinic Acid might not be too problematic for most people

@Microformulation I’m using very low concentrations of AHAs
Doreen

Member
May 18, 2018 at 5:18 am

@CedarWind108
I’m not sure if Paula’s Choice uses niacinamide in her AHA/BHA toners, but I do know that she uses a lot of actives in these toners. Full ingredients lists can be read on her website.
OldPerry

Member
May 18, 2018 at 5:48 am

And she sincerely believes that all the additives they use work. Whether they do or not, well, the science is far from settled.
Doreen

Member
May 18, 2018 at 7:03 am

@Perry
I agree. She does have great products however. And I think it’s for a reasonable price if I see all the pricey ingredients that are used. I do believe in general that most of the skin actives have a strong placebo effect.

@CedarWind108
I have read all the ingredient lists of the acidic BHA/AHA toners of Paula’s Choice. Unfortunately I don’t see niacinamide in these lists. I do see panthenol, which I thought is also sensitive to acidic hydrolysis, but perhaps panthenol doesn’t convert into a potential skin irritant, like niacinamide does?

All the skin actives in PC BHA/AHA toners (pH 3.2 - 3.

Vitamins

Panthenol

Sodium Ascorbyl Phosphate

Tetrahexyldecyl Ascorbate

Tocopheryl Acetate

Botanical Extracts

Camellia Oleifera & Sinensis Flower/Leaf/Stem Extract (Tea)

Vitis Vinifera Seed Extract (Grape)

Epilobium Angustifolium Flower/Leaf/Stem Extract (Willow Herb)

Avena Sativa Bran Extract (Oat)

Punica Granatum Fruit Extract (Pomegranate)

Lycium Barbarum Fruit Extract (Goji Berry)

Sambucus Nigra Fruit Extract (Black Elderberry)

Chamomilla Recutita (Matricaria) Flower Extract

Peucedanum Graveolens Extract (Dill)

Boerhavia Diffusa Root Extract (Red Spiderling)

Sea Whip Extract

Salix Alba Bark Extract (White Willow)

Salix Nigra Bark Extract (Black Willow)

Borage Officinalis Extract

Ulmus Fulva Bark Extract (Slippery Elm)

Lamium Album Flower Extract (White Nettle)

Arctium Lappa Root Extract (Burdock)

Aloe Barbadensis Leaf Extract

Camellia Oleifera Leaf Extract

Cucumis Melo Fruit Extract (Melon)

Glycyrrhiza Glabra Root Extract (Licorice) (and the potassium salt)

Isolated components

Tetrahydrodiferuloylmethane, Tetrahydrodemethoxydiferuloylmethane, Tetrahydrobisdemethoxydiferuloylmethane (from curcumin)

Epigallocatechin Gallate (EGCG, from tea)

Bisabolol (from chamomile)

Misc

Phytosphingosine, Phospholipids & Ceramides

Peptides

Allantoin (keep in mind that allantoin is amphoteric: it’s cationic under acidic conditions. The same is with betaine (trimethylglycine))

Adenosine

Arginine

Nordihydroguaiaretic Acid

Sodium Hyaluronate

Sodium PCA

Dipotassium Glycyrrhizate

Maybe this can come in handy, as it’s not always easy to find the recommended final pH for a product. Now we know we can use these at a pH of 3.2!