[Pharma]

Didn’t you know that probiotics and skin microbiota are super trendy?

Why not launch a kombucha cream or kimchi serum :smiley: ?

[Pharma]

lmosca said:

…
Maybe someone else on this forum knows more (thinking about @Pharma).
…

Thanks for the flowers! Though I know a lot I don’t know everything, sorry.

In its oxidised form (which is fairly stable unless exposed to heat or UV light), it doesn’t do much and I can’t see anything obvious. The only three effects it might have apart from being an important and potent antioxidant once ‘bio-activated’ are antimicrobial activities (only shown with certain bacterial varieties), emollient effects (much like similar small molecules), and maybe the kind of optical illusion as (not) seen with stearic acid based vanishing creams (dunno if you get that joke LoL). ALA applied as propanediol solution is likely to crystallise out once the solvent penetrates skin. The forming tiny crystal flakes on top of the skin might reflect light in a peculiar way which lets skin look brighter. But I’m speculating here!

AFAIK the cyclic oxidation product of dihydrolipoic acid (i.e. lipoic acid) drives it to preferentially undergo two electron redox reactions over nucleophilic attacks. How that should visibly and overnight translate to a brighter skin appearance remains elusive to me especially because it’s not that easily, let alone quantitatively and uncontrolled, reduced from ALA in vivo.

[Pharma]

7% ‘hyaluronic peptide’ would be possible…

[Pharma]

For example HERE. There are many more but they’re sometimes a bit tricky to find and even to find again…

[Pharma]

octylacetate said:

Will cetearyl alcohol be emulsifying enough to give a stable cream? 

Like @LuisJavier said, it is not an emulsifier but may increase emulsion stability if combined with a real emulsifier.

[Pharma]

In pharmaceutical preparations, it’s often 0.05-0.1% at a ratio of 3:1 though the product is usually stored in the fridge if used at 0.05%.

Apart from EU documents, I only have stuff written in German, sometimes not even available online.

[Pharma]

Hmmm… if you wanted to maintain hydration, you could switch glycerol for 1,2-hexanediol alongside some less traditional preservative.

[Pharma]

My hair also prefers sulfate-free shampoo though these usually come with a variety of drawbacks:

- Hair re-fattens faster = more frequent washing needed

- Difficult to find a good product (usually in organic/eco markets), most just don’t cut it

- Sensorial aspects such as creaminess, smell, visual appearance, lather etc. are often close to inexistent

From an economic point of view (that’s most of what @Perry is all about), sulfate-free detergents have additional drawbacks:

- More expensive

- Sourcing constant and large quantities of +/- identical quality (no batch-to-batch variation and no shortage) is not evident

- More time & efforts needed to come up with a pleasing & performing formulation

- Thickening agents other than cheap salt are usually required if a ‘consumer-friendly’ creamy texture is envisaged

- Preservation might be an issue (more different and more expensive preservatives)

-> Bottom line is, many sulfate-free shampoos aren’t made for the masses but rather dwell a niche existence.

The most obvious solution is cheating = using sulfonate-based surfactants. The same has been done with phosphates in laundry and dishwasher detergents. Fortunately, the practice of using phosphonates instead was for most companies a rather short intermezzo.

Imagine you meet the prince of your dreams. I’m oldschool in this regard, so I in his place wouldn’t ask you at one of the first dates what kind of shampoo I should place in the shower… but even if, you probably wouldn’t mind too much had the fresh love of your life a ‘wrong’ product in the bath. It’ll just be a good opportunity for some thorough re-education 🙂 .

Anyway, assuming he’s like me, then he’s probably going to ask you what food you like and which one you don’t. Say you didn’t like cabbage, are allergic to wheat, and could NEVER eat horse meat. What would you say if he’d invite you to dinner and served stir fried kale, durum couscous, and mule steak?

Technically, he’s serving ‘sulfate-free’ but practically… I wouldn’t be astonished were you to decide right then and there that you’d rather have a couple tiny Rocky Mountain oysters instead :smiley: .

[Pharma]

Will it work? Well, it sounds refattening, soothing, and nicely smelling and also like being great for growing microbes too. Apart from that, what is it supposed to do?

[Pharma]

lordofthefries said:

…school project…gel with a target shelf-life of 1 year…Are there any guidelines/ studies done to show various amounts added and their corresponding shelf-life?…

School project sounds like fun! Your proposed preservative has decades of intense use in cosmetics and pharmaceuticals. It is usually used at a fixed proportion. A water based gel will, if preserved adequately, manufactured properly, and filled in tubes but not jars or pipette bottles, be stable for up to a year. Given that your kids do not know what GMP is… I’d go with a 3 months expiration date at the most. Depending on composition, storage in the fridge might be advisable too.

Are there guidelines: yes

Are there studies: not applicable in your case

[Pharma]

Perry said:

…For example, why would you use ADANSONIA DIGITATA LEAF EXTRACT? What is it supposed to do?…

Baobab is soooo in trend, everyone needs it and it does everything which is good for your health and beauty! At least, that’s what I’ve read in some very reliable advertisements :smiley: .

Me, I wonder about the Adonis amurensis extract. Adonis species are toxic but exactly that toxin, which is hopefully lacking in the extract, is responsible for traditional use of Adonis.

4% horse chestnut extract is used in a registered medical ointment in Switzerland. Said ointment is brownish and anything but pleasant to apply but it helps wonders against varicosis, haemorrhoids, and other similar illnesses.

Regarding cetearyl olivate + sorbitan olivate: This is a o/w emulsifier which forms so called liquid crystal networks, your formulation doesn’t look like one which needs that. The only thing in your serum which requires emulsification is hydrogenated retinol. If you intend using equal amounts of Olivem 1000 and an inactive retinol derivative… The only thing keeping that emulsion stable is the super high amount of gelling agent (i.e. hyaluronic acid) and you’d be better off going with a solubiliser or an emulsifier without cetearyl olivate, cetyl alcohol, or the like.

[Pharma]

ngarayeva001 said:

…and lye.

Even wood ash would do the trick .

[Pharma]

Your % doesn’t add up to 100 but 74% if I did the maths right.

You can do a high internal oil phase emulsion as @ngarayeva001 suggested or rather, you actually have one already (adding oil + emulsifiers and adjusting total 5 gives 76% inner phase = slightly above theoretical requirement for a true HIPE. BTW PEG 40 HCO in your system is considered an emulsifier.

Some HIPEs are fairly easy to make, I even managed to create something after just a handful of trials which isn’t based on sucrose esters as sold by Alchemy Ingredients. Though these sucrose esters seem to me of being more reliable, more easily giving stable emulsions, and the sensorial is also great (if you like HIPE gels). Your product is likely not going to create a good HIPE because you have too much water and not enough polyol. I’m not sure whether you use the right emulsifiers though. What is PEG 7 cc? Certain PEG-based emulsifiers (that’s what all your 4 emulsifiers are) can be used to produce stable HIPEs, they’ve been used for this purpose well before Alchemy Ingredients got on the sugar rush.

[Pharma]

Intensity perception has nothing to do with vapour pressure but with how well a certain molecule binds to olfactory receptors, with its perception threshold, activation potential etc. It’s all biological effects in the olfactory organ but also how signals from there are processed in the brain.

High vapour pressure just means that said compound evaporates faster and you get more scent molecules into the air. However, this doesn’t automatically mean that said molecule has a stronger scent than a less volatile one!

[Pharma]

The two are not the same.

Non sulfate path? From a chemical point of view, you’re correct. Everything else, you’re likely not. Your two ingredients are sulfonates, chemically very closely related to sulfates and behaviour and environmental faith wise more or less identical, probably a bit better on this edge and a bit worse on the other but all in all, it’s the same. I don’t know for sure whether or not all these are really more gentle than SLS and SLES or just a few whilst most are in the range of SLES and the rest is hearsay.

Every time I see a ‘Contains no sulfate’ on a sulfonate formulation, I can only shake my head… the miracles and wonders of modern marketing or the question of ‘Is there intelligent life in the universe?’…

[Pharma]

As long as it foams, it’ll do. Basic rules of hygiene are key: not just regular hand washing or not touching your face, but also not eating with your fingers (and certainly not after touching money or a handle in a bus).

The best weapon is isolation and social distancing: Tell the people to ‘self-sustain’ wherever and whenever possible and keep a 2 metre distance (not just in the shop but also in the waiting queue in front of the shop).

[Pharma]

I haven’t found a book on antioxidants which would even remotely satisfy me ;( .

However, there is logic to it (apart from a lot of trial and error as well): redox potential which can be listed in an electropotential series (see tables & figures in THIS topic-unrelated publication). What this means is, that in order to protect substance A from oxidation, substance B has to be a stronger antioxidant than A. In case of BHT/retinol: BHT is a highly sterically hindered phenol which results in a more stable radical whereas retinol can be regenerated but also tends to react further and thereby would degrade irreversibly. Although both are phenols with similar redox potentials, BHT is the fall guy due to stability. But this is just an exception to the rule of redox potential.

Also, it sometimes pays off to choose couples either for one or for two electron reduction/oxidation but this may be more for lab settings. After all, mother nature goes with redox potential and spatial separation (lipophilic and hydrophilic antioxidants and different organelles for different redox steps). The latter is not readily applicable in cosmetics and doesn’t bring any benefits because a cosmetic product isn’t alive and constantly regenerating.

[Pharma]

PSP is just protein hydrolysate, nothing like a growth factor and Biopelle probably calls their peptides growth factors. It’s marketing, no more! I did work with several real growth factors in in vitro assays using cancer cell lines and fresh human blood and we also sell growth factors, growth hormones, and similar proteins (on prescription only) at the pharmacy. These are all very expensive and very unstable. Putting those into a cream or serum will have them fully degraded/inactivated before the bottle is fully packed. And even if, they do not penetrate skin and topical application does only deplete your money purse.

[Pharma]

The sunscreen comparison ain’t the best because most people still use not enough to get the indicated SPF. The result is not necessarily a sunburn but cancer, something which shows only in decades and upon repeated inadequate use. Else, you’re absolutely right; prepare for the fact that most consumers behave like brainless zombies. At the pharmacy, we’re also supposed to write something like ‘To be rectally applied 3 times a day’ on suppositories because simply stating ‘3 suppositories per day’ will have some individuals swallow them, put them in their ears or even sticking them on the ankle with a band-aid (seriously, no kidding!). Once, a doctor told the user of a decongestant nose-spray ‘Use as needed’… well, she had many needs and use them not up to 3 times per day for max a week but over about a dozen times per day for several months!

[Pharma]

Correct, it is an antioxidant. It’s great for removing air from the formulation, something tocopherol does not. Ascorbic acid does it too though not as efficient. Like ascorbic acid, metabisulfite is water soluble and also a good partner for tocopherol (both regenerate ‘spent’ tocopherol). It is a quite strong antioxidant and hence, does react with more ingredients (such as natural pigments) than other antioxidants but does not protect as long because it gets used up fairly quickly by the ever present oxygen if not used in an airless dispenser. It’s also a possible allergen (if memory serves me right, ~1% of the population is allergic to sulfites in food, tendency decreasing due to less abundant use, though no precise numbers are known).

[Pharma]

Acetone might be an option though I’d rather use ethanol where possible.

Alternatively, use dish washing liquids for lab equipment. These do not contain rinse aids (non-ionic surfactant which form a molecularly thin layer on your glass ware) or go with a DIY solution of pure SLS or SLES. After ‘shampooing’, rinse with deionised water.

[Pharma]

Okay, I see. The rather large amount of gluconate required (1/7 AminoSensyl) indicates that adding gluconate has nothing to do with chelation (gluconate at pH 5 does not act as chelate) but instead is an anion-exchange like turning sodium stearate into TEA stearate and salt. Gluconate is larger and more hydrophilic than the esylate anion. Although a weaker acid which probably reduces zeta potential, this 1:1 (estimated on a molar basis) switch mostly increases apparent HLB, increases Helmholtz plain thickness (= reduced coalescence), greatly increases interface curvature (= smaller emulsion particles), and ultimately boosts emulsion stability.

Switching gluconate to EDTA also in an equimolar ratio (which is, from a chelation point of view, utter nonsense) might be somewhere between the effects of esylate and gluconate if it were not for the fact that EDTA at pH 5 carries two negative charges. As an educated guess, this makes it highly likely that you lose instead of win. Imagining you were to use phytate instead of EDTA, things would go from bad to worse. Using citrate instead… hard to say; it carries 1 1/2 negative charges at pH 5 but is comparatively small. What you gain from it as a weak chelate may not be worth the downsides regarding emulsion stability.

However, if you need adding a chelate (as mentioned, gluconate at pH 5 is of no use as such), small amounts of EDTA might/should be tolerated. Noteworthy, do not subtract the amount EDTA from gluconate but add it in addition.

[Pharma]

Which emulsifier does require gluconate and why?

[Pharma]

Gluconate is good for high pH. It’s probably hyped by some… Not saying it’s not worth anything but I wouldn’t bet my money on it.

[Pharma]

EDTA is one of the strongest chelates which can be used for many different applications/industries over a broad pH range. Depending on what you want to do, it may be better or worse than alternative chelates such as gluconate.

Gluconate has one major drawback in cosmetics: with many metals it only forms stable complexes at high pH. It can also quite easily be broken down metabolically by all microbes -> a formulation which starts failing fill probably fail hard.