[Pharma]

Depends on the type and viscosity of the cream.

Diluting 1:10 doesn’t change pH in a way that someone in the cosmetics field would bother about.

[Pharma]

Dibutyl ethylhexanoyl glutamide and dibutyl lauroyl glutamide. However, they are only derived from more or less natural and petrochemical but somewhat natural identical ingredients though do not exist in nature. Likely a tad less synthetic than Oilkemia 5s and certainly better biodegradable but that’s about all.

Use the search function, you’re not the first one asking this question .

[Pharma]

EDTA is not a preservative.

I can’t say that I think your product idea that great. You could likely do as much with baking soda in water (adjust pH to 5-5.5). It doesn’t complex calcium but it does make hard water feel softer. And/or use sodium hexametaphosphate (best at neutral pH) or phytic acid (any pH) as a water softener.

All these are more eco-friendly than EDTA.

[Pharma]

It might be D5 ‘sweating’ because your emulsifier can’t handle silicone oils too well. This effect can result in something which feels like a w/o emulsion and shows such a sliding effect. However, it results in a very fine film of silicone oil on your hands. If you let water run over the ‘slip trace’, it will pearl off.

[Pharma]

My fridge has a tendency to make oils cloudy/foggy :smiley: .

[Pharma]

In Europe, dimethicone is not an active ingredient but an excipient.

[Pharma]

Abdullah said:

@Pharma ohh

Should the pH be higher or lower for citric acid to complex calcium? 

Higher.

Although: Does your tap water really have a pH of 4,5-5? Do you live in a peat bog?

[Pharma]

@Graillotion I’d go with 0.1% GLDA. Assuming you were to use considerably more Varisoft EQ 65 makes incompatibilities rather unlikely. A minor drop in stability (lower zeta potential = higher risk of breaking/creaming/sedimentation etc.) is to be expected but I would wager that you couldn’t tell a difference.

You might even get away with a small quantity of an anionic polymer. It will most likely be glued to the surfaces of the positively charged oil droplets. In that case, it will be necessary to include the gelling agent after homogenisation. This then will reduce zeta potential like GLDA does. Will it still increase viscosity? Dunno. Will it still ‘texturise’ your product? Dunno. Would a non-ionic polymer be the smarter choice? Most likely. What might be a good alternative apart from HPC? Maybe a silicone elastomer such as Dowsil EL-TIPS or a blend like Novatex MAT which comes with other ingredients you already use?

[Pharma]

Citric acid at pH 5 doesn’t complex calcium .

[Pharma]

Ah, in a shampoo… well, it could work… theoretically.

You’ll have to try. For hard water you’ll roughly need 600 mg EDTA for every liter of water you want to turn soft (if one neglects all the detergents, salt and what not within your shampoo). This means you can soften the part water used to produce lather with less than 100 mg EDTA in one application of shampoo but you can’t soften all the water used to rinse off your shampoo at the end and that might spoil all attempts at softening tap water without a ‘technical’ water softener.

[Pharma]

Microformulation said:

…Way back in 1984 when I attended Pharmacy School, they sure made us learn the mechanisms of action for these two drugs.

Acetylsalicylic acid has more than the two mechanisms you probably learned about and way more in vivo effects than what was thought twenty years ago. When it comes to paracetamol: We still don’t know how it works, seriously. One of the oldest drugs still in frequent use, one of the most prescribed ones too, one use during pregnancy and breastfeeding, and one of the most stimple molecules in the realm of synthetic drugs… and we don’t know where it binds and what it does to our body. You explain that to me 😉 !

And now you imagine that science trying to elucidate the mode of action of a mixture of 100 different small hydrocarbons aka an essential oil…

@Abdullah Yes.

[Pharma]

Depends what you define as ‘effectively’.

For cosmetic purposes, magnesium is never chelated good enough to be of any benefit and calcium, especially at low pH, is nearly as poorly bound.

In general, I wouldn’t use EDTA for chelation of magnesium and only for certain applications when it comes to calcium (e.g. cleaning chalk deposits or in in vitro tests).

[Pharma]

EOs applied to skin are bioavailable to about 50% (they penetrate skin easily and pass into the bloodsteam) and to a good part are excreted by breath (quite unique behaviour). Some EOs have medicinal properties pretty much like ‘chemical’ pharmaceuticals and ‘drugs’. Unlike many standard drugs, they don’t have one defined molecular target and one scientifically proven mode of action. But neither do Aspirin and Tylenol .

Multi-component mixtures are simply very difficult to grasp scientifically, that doesn’t mean they’re not acting ‘scientifically’ or only work by placebo effects.

However, antipsychotics, according to the latest investigations, act primarily as placebos and, though we know to which receptors they bind and which neurotransmitters they affect, we don’t know how and why they truly work (if they work at all… patient-doctor relation is more important according to above mentioned investigations).

[Pharma]

@Abdullah Good point! Phytate certainly is a problem. Citric acid (useless as chelate = don’t use it), EDTA (at pH > 5) and GLDA (at pH > 4) can be but don’t have to be (keep their concentration as low as possible). Caprylhydroxamic acid (though personally, I despise it) would likely be the only official chelate possible. Certain polyphenols such as chlorogenic acid and EGCG may be used instead though they’re mostly only good for complexing iron ions.

[Pharma]

In cosmetics, MCT is usually the same or close to CCT, same hydrolysis of coconut triglycerides, followed by distillation of medium chain fatty acids (caprylic and capric acid for MCT and minor amounts of caproic and likely larger amounts of lauric acid for CCT), and subsequent re-esterification with glycerol. Given that lauric acid is a major fatty acid in coconut oil, MCT may contain more of that one. However, MCT is often just CCT because lauric acid is often used for other purposes and caproic acid is omitted because it occurs only in negligible amounts and reeks of goat.

Cosmetic grades don’t really care for % and purity in some regards. As an example, stearic acid in ‘stearic acid’ may be less than 50% and palmitic acid being the main constituent. Only because something is called CCT doesn’t actually mean it’s only CCT nor does it give any hints on the composition like tricaprylin and tricaprin versus mixed triglycerides (capric-capric-caprylic, capric-caprylic-capric, caprylic-caprylic-capric and so on). CCT simply implies that the main fatty acids are capric and caprylic acid whilst in MCT there could be a huge amount of lauric acid esters present.

Viscosity, melting/cloud point and other such characteristics may give hints.

[Pharma]

INCI is not a good nomenclature, it’s just something for consumers to read on the back of a package. Chemically speaking, INCI sucks and lies… at least, it gives certain hints to what the ingredient could roughly be.

CAS is more precise but still far away from IUPAC nomenclature and often refers to a product family (like many polymers).

[Pharma]

Perry said:

… -CH2-CH3… 

More precisely, it’s (-O-CH2-CH2-)nOH (as usual, me being nitpicking).

Ethoxylated compounds are synthesised with ethylene oxide which in turn is a possible/likely carcinogen. It’s a gas and proper synthesis and work-up will remove it. However, the limits for ethylene oxide are very low and hence, it may happen that traces remain. What’s currently happening more often than contaminated cosmetic grade ethoxylated ingredients are organic sesame seeds from India being contaminated with it because in India, it’s okay to fumigate food with ethylene oxide (it’s super easy to use and kills everything from bugs over bacteria to fungi and even spores). We had several product recalls from different manufacturers down to consumer level because fumigated sesame seeds were found in breakfast cereals and the like. Consumers were most likely never at risk, it’s just that in Europe there’s a zero tolerance for ethylene oxide in food.

[Pharma]

Some thoughts:

- Given your nickname I assume you’re female. Else, it is recommended not to handle female hormones (at least not on a regular basis), even with your safety equipment.

- Progesterone is considered a prescription drug in many countries.

- It isn’t that pH sensitive, best to keep it below pH 7.

- Interactions: Could you be more precise? Chemically, it’s quite stable, if that’s what you’re asking. Just to be on the safe side, don’t combine with good nucleophiles such as free thiols.

- It’s best soluble in medium polarity solvents such as alcohols (progestogel, a pharmaceutical product, is a hyroalcoholic gel). What you could or have to use depends on the final concentration and where that cream will be applied.

- You could also go for a suspension instead of a solution: jojoba oil is used in magistral preparations to obtain a 10% stock suspension which can then be integrated into oilier creams.

- Other preparations such as vaginal suppositories (suspensions, not solutions) are based on macrogols.

May I ask what you’re planning? What you’re planning doesn’t sound like cosmetics…

[Pharma]

There’s a fairly recent post about (natural) toothpaste on this forum .

[Pharma]

Most but not all MCT oil is caprylic/capric triglycerides. Depends on the quality and the definition of the manufacturer.

[Pharma]

From what I could find out: It’s a phenol (obviously) and one of the better antimicrobial ones when comparing to other non-halogenated ones. However, halogenated phenolics such as triclosan often have an inherent better activity.

EU limits the amount to be used in cosmetics. Given that it’s a phenol derivative, potential skin irritation and hypothetical toxicity may be reasons, scarce literature another (though it’s been around as cosmetic preservative and other applications for 40+ years).

Can’t find my notes right now… it is quite similar to the regioisomer thymol regarding its effects (against some microbes a tick better, against others a tick worse) but has one huge plus; unlike thymol, it’s nearly odour- and tasteless.

[Pharma]

Polyamides are as synthetic as it gets .

[Pharma]

Clove EO contains mostly eugenol which is, like lidocaine, a local anaesthetic. Cloves were used for centuries against toothache.

Pro: Very good skin penetration

Con: Strong smell and rather short action because of fast resorption and volatility

[Pharma]

@prow18 Bingo! 🙂 More precisely, it’s not just mixing the two but chemically reacting them with each other to form a new hybrid molecule, one that doesn’t exist in nature.

[Pharma]

Uppss… Typo-alert: just realised that the second ‘o/w’ of the three should be w/o (i.e. the hot PEG emulsion).