[Cst4Ms4Tmps4]

Oh, it’s you again @Pharma . I don’t know where in the world you dig so much peculiar data.  Thanks science I get to learn from you. I’m always seeing spirits of alchemist, astrologers, and priests in ancient past, which is cool. I’m not ‘complaining’. ROFL!

Ugh. What you mentioned confirms my confirmation biased of my own informal, self-funded, and insignificant research experimentation and lowly observation.

Dafaq….so now that particular “saccharide isomerate” is brightening complex!?!?!?!?! Maybe I am not tanned enough to see the effect. Maybe I did not use for ‘some weeks’ to see the effect. I am very confused.

There again, the psychological tactic. A massive list of % but no mention compared to what.

I am not a chemist/pharmacist but I know for certain that Tretinoin works.

Brightening - Tretinoin
Receptor thing - Tretinoin
Melanin & pigmentation - Tretinoin
Reduction everything except body fat- Tretinoin
Collagen/stimulation - Tretinoin
Mess/modify genes -  Tretinoin

Although I DIY my moisturiser and worship Urea, I still use 0.05% Tretinoin cream. I worship Tretinoin in actuality. Urea et al, is just as moisturiser, purely to moisturiser.

To me, Tretinoin is the king & queen of beauty! Many people say that my skin is better that that of female. I kid you not! Koreans have insane 6 to 9 steps regime called “glass skin”, shines like no body’s business. I have only one step and get similar shiny skin, saves me much money and time. Work smart, not work hard. Bonus is my skin is clear of blackheads that even Salicylic Acid can’t reduce. I mean Salicylic Acid can reduce blackheads but it does not linger like Tretinoin. The ‘clean/nice effect’ continues for quite a while after the application of Tretinoin is stopped, could last for many months depending on an individual’s genetic makeup, lifestyle, and external factors.

Hence, by marketing logic I would say this “Tretinoin is 251% more effective. 77 times cheaper. Increases beauty factor by 168%”.  Compared to what? I don’t know. Use the imagination. Hahaha!

[Cst4Ms4Tmps4]

@janele
I tried ‘making’ Pentavitin. Hehehehe.

I tasted it. It has caramel flavour. And so I boiled Sucrose with 1% Citric Acid (add some water. 2g Sucrose can dissolve in 1g water). Boil the solution until its temperature reaches about 110°C. This process splits Sucrose to Glucose and Fructose, basically honey.

I compared Pentavitin and my fake ‘honey’. Pretty similar. But Pentavitin is a little less viscous and more spreadable. Because it is business (yes I contacted them. More like harassed them. LOL) the company is secretive about its data.

I digress. 

Because it is a ‘trade secret’ I safely presumed that it must have something else done/added to it. And so, I added a little nonionic surfactant. Voila! DIY Pentavitin! Certainly Pentavitin does not foam! Mine foams! 

I do not know about the binding of amino acid though. It is washed away, it is washed away, no ‘high water retention’. I thought 5% was too little, I slapped pure Pentavitin without mixing it with anything. Same story. Oh well, I thought maybe once is not enough, I did the same thing (using it straight from the bottle) for days, 2 or more times in a day. Still the same, nothing special.

I don’t believe that my skin desquamates every single day! I am more than sure that I do not scrub nor use any ‘harsh’ surfactant.

I was given a brochure all about Pentavitin. Still, not enough data. The classic “$54 cheaper. 39% more”  psychological tactic.

Cheaper than what?
More than what?
Relative to what?
“Better/superior” compared to what?

I concluded that it is another marketing. The company told me that I need to use it for some weeks. Huh? Some weeks? Isn’t all things/products need few weeks of application in order to see some positive results? Slathering petroleum jelly or Glycerol can do the same thing anyway, if used for some weeks, and these two are considered gold standards for valid reasons.

[Cst4Ms4Tmps4]

@ngarayeva001
It is very soluble in water! I do not know how soluble it is but I manage to make a solution of it, 60g or 60% in water. I do not know where you live, for me is easy for it to be dissolved due to the high ‘room temperature’ here.

Many Asians making (silken) bean curd had long replaced Citric Acid and Boric Acid with GdL. Without scientific data they learnt that it has something to do with heat. Not only it is far less sour than other acids (at the same gramme), but also makes the smoothest and most even bean curd because GdL can be properly mixed in and the soybean milk has chance to rest and stay still while proteins are being coagulated. With Citric Acid the result is nearly instantaneous regardless of temperature, bean curd like this is gritty, uneven, and if ‘unlucky’ it tends to and prone to oozing liquid (syneresis).

I presume you tested pH while it is not completely turned to its acid form. GdL is slightly sweet! I do not mean sweet as an expression, it is truly sweet. Taste it! Very soon it turns sour. I assure you, its pH is proper low once its devilish side of metamorphosis is complete. Depending on concentration, it will start to sting your eye, wound, etc. Oh, also depends on concentration, pH is low enough to make your eyes squint and make funny faces. I guess the latter is the best evidence!   

[Cst4Ms4Tmps4]

Jeez! When comes to Glucono Delta Lactone, I am already an expert! Hahahaha! Oddly enough, what is inexpensive to you (all) is expensive to me, vice versa. I have plenty of GdL at my disposal!

Heat the solution! Need not rolling boil. Need not very hot. No “heat and hold for 20 minutes” nonsense. Heat it (GdL in water) up and the solution magically turns acidic quickly. Yes, quickly. Very, very quick. No more tens of minutes to hours of waiting. Not even a minute, depending on what you use to heat things up. I nuke mine in microwave or mini jet lighter.

Don’t believe me? Add some base like you would neutralise an acid or use some pH testing thing to ‘see’ the change. The magic is truly instantaneous. I do not seem to get bored repeatedly watching it as it happens.

[Cst4Ms4Tmps4]

After I spent so much money and effort trying Sodium Hyaluronate and Hyalyronic Acid due to my gullibility, I concluded that they are not as superior to anything. Really is a marketing thing.

Firstly, they boast God-given power to absorb water 500 to 1000 times their weight. Most thickeners and suspending agents can do it. Carbomer can do it and do it much better than HA/SH.

Secondly, it claims to ‘hold’ water due to the water-sucking power. Like Urea which everyone seems to say it is a humectant and very hygroscopic, I wet it and let it dry, it turns back to crystal/powder/solid.

Only after learning about a peculiar phenomenon called ‘deep eutectic solvent’ (credit goes to @Pharma ) did I see through the trick. I presume it is identical to layman’s term “impurity”. Only a little Citric Acid in Urea solution renders Urea liquid/syrup for ever. I thought it was low pH, so I tried with a little Propylene Glycol and a little other stuff, I obtained the exact same result-Urea just won’t recrystallise. It was a WTF moment for me!

True enough, those so-called “tests” are a mixture of other things such as base cream as showed by @EVchem. The claim/marketing is a guaranteed failure if they tested it (any substance) as it is (single it out).
No different to Grapefruit Seed Extract as preservative-free natural-organic preservative, manufacturer never tells that it is laden with parabens, Benzethonium Chloride, Triclosan. 

I am not very sure about the “500 Dalton Rule”.

[Cst4Ms4Tmps4]

Ah yes. I understood what @Pharma really means. I think I am rather similar to him. There are plenty of ready-to-whack stuff but I knowingly and deliberately chose the ‘suffering/stupid’ path kinda, sorta, as though, as if recreating the wheel. This is the “fun”, the thrill.

“Complain” refers to groan, repeatedly comment one’s dissatisfaction.

Complain long enough becomes “whine” or “whinge”. 

Some people in my countries take ONE comment overly serious. A friendly suggestion becomes a dire complaint.

Perhaps my understanding of the English language is very bad.
Maybe comment=merely say/state=vent=complain=whine.
Toe-may-toe=Toh-mah-toh.

https://www.psychologytoday.com/us/blog/the-squeaky-wheel/201210/the-difference-between-complaining-and-whining

[Cst4Ms4Tmps4]

@Pharma

This is also a quick one, from me, for now. I actually wrote another ‘essay’. Hehehe! There are a few words I notice you keep repeating. The more I look at them the more they are all interrelated.

I just do not know who the heck you are but you….are just…almighty! You sound like two Emeritus Professors of mine (one is an experimental and theoretical physicist, and the other one is a philosopher). Keen to share, very complicated explanations, highly technical, outstandingly detailed, no BS, not arrogant. Sadly, I had no chance to properly thank one of the two professors as he pushed the daisies. Without them I genuinely had trouble sleeping. My curiosity of how the world works is off the chart. Qualities such as theirs nearly extinct. (I certainly make use of what I learn and be practical about it. Meaningless to merely know and know for the sake of knowing without true purpose. The only way to remember a skill or knowledge is to practise; use it or lose it)

a) Oh no. I did not make the list of properties of TMG. I copied the claims from DuPont presentation and other sites selling TMG.

b) Yes. TMG. Not the surfactant betaine. I wager you did not open the links I provided. If you saw one of the links it really is TMG I referred to, a supplement as said.

c) Yes spreading. As one of the claims-it is a “natural” surfactant/emulsifier. One of the characteristics is reducing water surface tension, not just spreads like water.

Ah! Always only the wife gets “angry” about all things. LOL! Enjoy your weekend and meal!

[Cst4Ms4Tmps4]

@Pharma
Yes. As a learner that I am, I need to maintain some level of humility. The half cup full/empty philosophical attitude. LOL! Unlike some people, I hardly ask for the sake asking and not try things out. I constantly see people either in forums or in real-life do just that, I think all they truly need is talk therapy.

You’re good! I wonder why you know about bubbles! Hahah! Not everyone knows the ‘carbonate’ part until they know, I am one example of such. My first experience is with Carbomer, it was hellish! Not only does it bubble, heat is produced. I thought it is an awesome reaction!
I am worry about bubbles. However, no thickener added, nothing thickens, so no bubble concern. Anything that bubbles such as Polysorbate 20, I add it last. (I mentioned it foams only because MCT is added and to properly emulsify MCT. I can gently stir the solution if without MCT)

I was sent to abyss once again! Hahahahah! I immediately checked for Trimethylglycine or Glycine Betaine availability here. Gosh, the price…! Trimethylglycine which I found exists only as supplement. The cheapest I could find is Biofinest brand. Very 100%. Very anhydrous. Very natural. Very organic. Very healthy.

Supplement is what I could find. I don’t know how true is their 100% pure. Science never claims 100%. The purest is 99.999999%. Of course people who know me in person know that I suffer from accuracy and precision OCD. 

I hope anyone could tell me the brand Biofinest is a trusted brand or not. If the brand is reliable and the content is really “100%” anyhydrous Trimethylglycine, I certainly would use only this ONE to replace emulsifier, humectant, et al. I said one because that is what the Internet says:

- 1% Trimethylglyine can emulsify 0.5% Salicylic Acid
- Not sticky
- Can reduce stickiness (of other ingredients)
- Superior to all surfactants and emulsifiers
- Superior to Glycerol (40% improvement in hydration as opposed to only 6%)
- True osmolyte
- Excellent spreading

Seems and sounds like God’s send. Seriously sounds like just that one thing slap on my skin will do, end of story and carry on with my life. No other ingredient to worry about.

No, no. I do not like Polysorbate 20. I dug out a big bottle of it, I bought it many moons ago, in year 2009. I suddenly found good use for it. It acts as wetting agent perfect to providing uniform coverage. This is the reason why only 0.5%, more than enough to significantly reduce water surface tension. It is not for emulsifying MCT. I added MCT as bonus, not a planned thing, because my previous experience told me that a little MCT acts as a detackifier, it was a startling discovery! ROFL!

In relation to HLB I use this one to do the calculation for me. How very strange that Caprylic/Capric Triglyceride on that page has an HLB of 11. I always thought MCT is equivalent to CCT. Yet, on other sides such as this one, I was understood that it can have an HLB 5! Ah….I suppose to find out from the seller/supplier for the accurate answer, yes? Keep dreaming! LOL! Don’t get me started with another rant and rave! To cut the long story short, I am banned/blocked by many of my own c*ntrymen for questioning them. The majority of Malaysians is ultra sensitive, zero intelligence to read between the lines, sarcasm, or humour. They want easy and fast money, hence why they have no time for FAQ, you want to buy you buy, you don’t want to buy STFU. Above all, many of them are only experts in selling, very very few of them actually know what they sell, even fewer of them with analytical ability and skeptical attitude.

Right from the manufacturer’s data of the MCT I have: C8 and C10 (Caprylic Acid and Capric Acid) C8 - 60%, C10 - 40%. No HLB value mentioned as it is for consumption, sold at a pharmacy. Some substances that I use are either from the bakery shop. It’s because the same substances are sold at unreasonably high prices with the “skin” label. No different to “organic/natural” label. I’m doing it for myself, therefore I have no users to sue me for making mother nature cry.

Span of any kind is either very expensive or nonexistent here. Tween 20 and 80 are the most common.

Oh no. Not at all. I do not want to quench all! Perhaps I did not explain well. Let me rephrase…

I certainly remember and know what you mentioned before this. I did read the part you wrote “Now that you know why you don’t need that much buffer but rather a stable product to start with, this huge quantity of citric acid doesn’t just sound stupid from a cosmetic point of view“. In other words, I probably need only 0.1% Citric Acid (or Sodium Citrate made in-situ). I also understood that the amount of salt/acid is irrelevant, pH is utmost importance, as long as the pH is at 6.2 will be fine. I won’t let your little fingers go to waste. LOL! Why do you think I started using the word “quencher” instead of “buffer”?    

So, what’s with that much salt then! The high amount of total combined salts is for their humectancy, hygroscopic, or moisturising properties. Yes, this is it! Nothing fancy!  I always find that salts are “better” than sugars/polyols in terms of hydration. Above all, salts mix really well with water, just stating the obvious. I tested with few sugars/polyols such as glucose, fructose, trehalose, they tend to form cloudy precipitation. Maybe is the pH too low for them. Salts, on the other hand, have not such issue. And salts are not tacky, if used wisely.

I will reduce the total amount of salt and see how it fares. I will start with Citric Acid/Sodium Citrate not because it is 3%, but because Sodium Citrate doesn’t give a nice feel, it is probably good only as a quencher. Sodium Gluconate is rather similar to Sodium Lactate in terms of feel, minus the horrid fermented smell of milk (more like rotting milk). Sodium Salicylate must stay as it is because it provides amazing result, real result! Incidentally, I realised that Sodium Salicylate has very slight oily feel to it and can very slightly reduce tackiness, I guess thanks to its persistent greasy benzene ring even in its salt form.

You mentioned two more very high level substances. Isoamy Lauryl and Coco Caprate. They are for the purpose of acting like Cyclopentasiloxane to reduce tackiness, to increase slip/glide, and to impart ‘dry/powdery’ feel? Isoamy Lauryl is the only one available here and its price is okay for 100g.

I will skip other high level substances for now. I will try the God’s send Trimethylglycine first. Need some people to tell me if the brand Biofinest one is actually reliable and real. The content inside the brand, to be exact.
I have been and am “collecting” more and more substances that I don’t really use and can’t really use! OMG! I also wasted insane amount of money on only 1g Sodium Hyaluronate as it does nothing as the world claims it does! OMG over and over!

Not an issue if Biofinest is another BS thing. I can always make do with what I can easily obtain and inexpensively, although they don’t give reasonably comfortable feeling.

[Cst4Ms4Tmps4]

@Pharma
It is I, again!

I was on a mysterious spiritual Out of Body Experience. Backed by pseudoscience, of course. It is certainly an euphoric surge.

I read lots about “shielding” but could not get a proper visual in context of the interaction of different substances as what you showed (carb-…TEAH+…citrate3-…TEAH+…carb-). This one doesn’t help, I can’t see the electrons and protons, I can’t see how they work. So, I did more digging. LOTS of digging! DEEP digging! Only one image shows exactly how shielding works.

I didn’t know why you kept saying calculations are useless. Now I know the reason why! I was using only Citric Acid, all seems fine and well, seemingly automatically giving me around pH 6 without me even sweating.

Last week I started to do like what you mentioned, that is to have a quenching system to cover a broad pH range and “double-edged” functions. This is when calculations fail. I end up constantly checking pH using pH strip.

Here is my ‘best’ product yet. No thickener. No Carbomer-electrolyte nonsense. 

2% Gluconic acid
3% Citric Acid
2% Salicylic Acid
q.s Sodium Bicarbonate

10% Urea
0.5% Fumed Silica
0.5% Polysorbate 20
0.5% MCT (maybe is the same as Capric/Caprylic Triglycerides)

****2% Sorbitol****
****5% Propylene Glycol****

1) Fumed Silica is to replace ester and fatty alcohol for that ‘dryness’. I notice it also actively dries sebum and sweat, I guess something to do with surface area. My nose and oily parts still shine after some time. I guess 0.5% is too little to suck up that much oil.

I live in the tropics. Ester and fatty alcohol prove to be a bad choice! Still too ‘heavy’. I guess something to do with carbon chain. I notice that the longer the carbon chain the more I feel the discomfort, and my nose “sweat” on high relative humidity condition. I thought it was only me. I gave it to a few friends to try it out and experienced the same. Very few of them use cream/lotion designed in the temperate countries (e.g, Eucerin, Sebamed),  do the same thing to them even when they are using those that is made for oily skin. On cool days or in an air-conditioned room we feel as normal.

Likewise, plants of all kinds temperate species fail to grow here, except at the highlands where the temperature is chilly. Rosemary, for example, the advice we always see is FULL SUN. Do it here and no amount of science will resurrect it.

2) I read Lonza Geogard Ultra PDF on the buffer part. It says add Sodium Citrate and then raise pH to neutral and then lower pH down to about 5.5. I was like why should I do that! Deliberately and completely neutralising Sodium Citrate only to make it acidic again? Might as well making Sodium Citrate in-situ as what I have been doing, all in only one step.

I dump all three acids in and neutralise all three at the same time and get around pH 5. I know I ought to be targeting pH 6.2 as you suggested. I doubt pH 5 is an accurate reading, let alone getting near to 6.2. Because I use pH strip.

I don’t have a pH metre. I don’t think a pH metre is suitable for me style as I make very small samples, 10g each time, to save cost. I am not doing a business, I won’t be getting the money back.

Another downside of a pH metre is the need for it to be calibrated often for accurate measurements. Adding insult to injury, the buffers used for calibrating the metre are not inexpensive.

NOTE: I bet at least someone sees why bother neutralising Salicylic Acid and becomes an eyesore!  Salicylic Acid is the only hydroxy acid which remains active even if it is neutralised. The salicylate still has that benzene ring that I assume is lipophilic. It’s effect on skin is slightly delayed compared to Salicylic Acid at low pH. Personally, I chose the least irritation path. Salicylate does accumulate in the skin. Correct me if I am wrong. Hence why, I’m not worried that I am ‘wasting’ Salicyclic Acid.

Sadly, I don’t know how much is “enough” of the salts to make an effective quencher. Calculated by stoichiometry when fully neutralised is a whooping amount of 8.4% of salt total. So, at about pH 5 - 6 probably is 7-8% salt. Mighty much salt.

With that much salt, the solution imparts tacky feeling typical of what salts do. I do not know whether they crystallise on the skin or not as you said, but they are tacky to me and definitely not dry and crystal/shiny glitter is not seen.

- Maybe they are not “normal” dissolved salts. Some salts such as Sodium Lactate don’t seem to recrystallise even in low relative humidity. Similar to fructose. Fructose deliquesces rather quickly and never recrystallises unless tremendous amount of external energy is given to turn it into powder once more. Sodium Chloride will happily recrystallise anytime of the day, shiny glitters can be seen, I can feel the “roughness”.

- Maybe the relative humidity here is already high that it hits salts critical relative humidity values (Oh ya! This is a big phrase for me!).

Talking about hydrogen bond, I think hydrogen bond is responsible for that dreaded tackiness, and the level of tackiness is determined by the amount of hydroxl group. NaCl is not tacky and readily crystallizes because it devoid of hydroxyl group.

NaOH has only 1 hydroxyl group but its critical relative humidity is 8.25%! WHAT! With this information, I changed my mind. I think it is not the mount of hydroxyl group that matters. I think it probably is due to electronegativity, the size of an atom, the distance between its electron cloud and proton, neutron.

3) I don’t know whether or not I need Sorbitol or/and Propylene Glycol added.

I read that Sorbitol is a replacement and superior to Glycerol in most aspects. It’s the slowest to lose water compared to the gold standard Glycerol. It is a “just in case” thing in case the salts decided to recrystallize on skin for reasons and conditions I don’t know. From my observation, Urea can recrystallize! This is the reason why I never see it as a humectant. It probably is humectant only if it gets enough moisture. It definitely is not one of those deliquescent substances.

I read that Propylene Glycol can reduce tackiness. But then I have Urea. I remember that you said that mixtures of Urea and Propylene Glycol are often tacky. Maybe Sorbitol may also increase tackiness in the presence of Urea.

Urea does sound like it is very powerful messing about hydrogen bonds! No wonder nothing replaces it for severely dry skin.

From my experience, 3% MCT works very well as detackifier! However, that time it was with Carbomer. Now that I have loads of salts I go with Xanthan Gum. Better still is to make 100% liquid emulsion as thickeners tend to be tackiness (I don’t know why I’m in so much tacky business!  ). For this to happen, Polysorbate 20 must also be raised to 3%. Sounds reasonable? Not really. Polysorbate 20 is some other species of its own, it doesn’t behave as other surfactants because still foams in the presence of lipids! I cannot stir the mixture gently to avoid foaming as MCT and Polysorbate 20 won’t be mixed properly. Even 0.5% it foams like crazy, and its foam is frighteningly fine and stable!

Leave 0.5% Polysorbate 20 alone, make MCT 3%?
My tests show that the maximum Polysorbate 20 to MCT ratio is 1:1. Argh!

[Cst4Ms4Tmps4]

@Pharma
Hey! I see that familiar Plumeria. Long time no chat! I do miss and think of you often behind this screen. And I do often re-read, re-think, and re-research WTF I asked you and what you shared with me. It is because with more and more data I gathered, more and more I learn/learnt, the more you share/shared, the more I communicate with other people, the more I “believe” that “pharmacists” like you are truly crazy about chemistry related to all things human. Only in my chemistry journey did I know that there are physical chemists, organic chemists. Ugh, the many chemists that I did not know before this!

Assuming pharmacists know their shit, that is. Pharmacists here, where I live, are stupid AF and I never consider them “chemists” (or apothecarists) as what pharmacists were traditionally/archaically known as. They (the idiots here) do not compound their own drugs. I’m not a pharmacist but I know and do a lot more science than they do.

Anyway, I decided to not use colloidal oat after learning that it is rather troublesome as it needs to be hydrolised.

Errr, I mean not a must to be hydrolysed, probably is my perfectionism acting out. Hydrolysing it does make oat extremely ‘fine’ (and gel-ish) without using oat powder; I use instant oats and let 1M NaOH do its magic.

Since @MarkBroussard says colloidal oat is actually an active skin protectant which I safely assume that it is not a claim thing, I might try colloidal oat just by itself without hydrolysing it. And also as what you mentioned, simply slap and slather that colloidal everything right from the carton/tin, why bother the extra steps!  

I will presume preserving that much organic matter will be painful. However, I do know that DMDM Hydantoin is the best preservative as it is not sensitive to any substances. nothing deactivates it, not temperature and not pH sensitive, covers the headspace. I am not selling my products so should be exceptionally fine using DMDM Hydantoin.

[Cst4Ms4Tmps4]

@Belassi

Yes. By Tesco, for Tesco, of Tesco, in Tesco. I live in Malaysia. Tesco is in abundance over here!

I guess that you consciously or unconsciously targetted for 1M NaOH.

I bought NaOH and realised that it is a monohydrate one! I did not know there are anhydrous and its hydrates! I admit that this is my first time handling NaOH. I pray to Strong Alkaline God that it protects me from all forms of strong alkali harm.

So, for anhydrous one will be 4%. For monohydrate one will be 5.8%. Averaged these two I got 4.9%. This made me to think that you probably (unintentionally and unknowingly) went for 1M NaOH.

[Cst4Ms4Tmps4]

Doreen said:

??
It’s just oat flour!

I know, right! Not where I am! 🙂

Oats flour is considered ‘organic’ and can only be found in organic ‘specialty’ shops. Most of us, who are wide awake, know that when that label is on everything, price tag is also very organic. :lol

The cheapest Oats we have here is Tesco brand Oats. Very cheap to the extent that I could literally bathe in it! Makes no sense..but…yeah…..business thing is beyond me.

[Cst4Ms4Tmps4]

@Belassi

All right. The amount of NaOH is still a mystery! Haha! Maybe you have already found cost-effective pre-made Oats hydrolysate (or other hydrolysate) that you no longer care to DIY.

I manage to find very cheap NaOH and POH. I will get either one of them by tomorrow, I hope.

Grinding my/our own Oats seems to be the best and cheapest, although not the most convenient. Pre-ground (powdered) Oats is very expensive.

[Cst4Ms4Tmps4]

@Belassi

Wow! Uhmm… There is not really a measurement of how much NaOH is used? This NaOH part is very confusing, actually. 

I will assume 5% NaOH solution, does not matter how much as long as “put enough Oats” and observe the smell (not sure what odour) and colour (brown) change that occurs immediately.

AND THEN dilute the needed ‘random’ amount of the reacted compound with as much water as needed (to making the final product such as lotion, cream, toner, whatnot).

Finally, neutralise the whole thing (hydrolysed Oats and newly added Water) and observe the colour changes back from brown to Oats’ original colour again.

That is my plan in my head. I neutralise it later/when I need to use the hydrolysate because I think that the alkaline solution could effectively preserve itself. Also, I think by this way I would not be bounded by the 5% salt in my final product (I love Carbomer. You know how ultra sensitive Carbomer is to salts!)

Oh by the way, do you filter out the Oats? Or the Oats seriously really completely totally “vanishes” during hydrolysis? If this is true then vanishing Oats is the best indicator of readiness, yes?!?!?!??!!

[Cst4Ms4Tmps4]

@Belassi 

How do you actually hydrolyse oats? I mean, have you managed to figured out what you exactly you did that few times?

How ‘dilute’ is dilute?

100g H2O
5g NaOH
100g Oats

Is that correct?

OR you meant make 5% NaOH solution first, and then fill up a container with 100g Oats, add 5% NaOH solution just enough to cover Oats, add some more 5% NaOH solution so that oats are seen suspended in solution?

How do I know all those oats are properly hydrolysed and not a bit left un-hydrolysed? Oats are properly hydrolysed when each bit of Oats is blacken/darkened?

I do not know why the Internet very vast we cannot find how we could easily make or DIY Oat hydrolysate. Weird.

[Cst4Ms4Tmps4]

@Pharma

A quick one.

This only gets more and more interesting.

Is Triethanolamine Citrate a good buffer (neutralised Citric Acid by Triethanolamine) ? Is the Triethanolamine part a weak base and is another buffer on the alkaline side making the buffer wobbly-wobbly?

My understanding of “salt” and “ions” is suddenly lost since I discovered that Triethanolamine does not ‘split’ into smaller components in neutralisation as NaOH or NaHCO3 does.

NaOH -> Na+ + OH-

NaHCO3 -> Na+ + HCO3-

Triethanolamine -> Triethanolamine 

And since Carbomer is sensitive to metal ions, I thought that Triethanolamine the most suited to neutralising Carbomer and be a buffer in Carbomer.

In my test though, Carbomer turns to liquid all the same, does not matter whether Triethanolamine Citrate or Sodium Citrate. LOL! However, there is a slight improvement with Triethanolamine Citrate. Very slightly. Few people said why bother if it is only very slightly. In response to that I said we use Carbomer for a few valid positive reasons.

I guess that having ONE sodium based base to neutralise Carbomer and ONE Triethanolamine based salt in buffer is better than having TWO sodium in buffer and to neutralise Carbomer. Sodium ions accumulate. I can be wrong.

Sad, no chelator to chelate sodium and monovalent metal ions. Maybe there is, maybe is polyamine, but I doubt it is worth getting it.

[Cst4Ms4Tmps4]

@Pharma
@Bill_Toge

You two “may be” correct!

Look what I have found!

https://personalcaretruth.com/2011/06/a-closer-look-at-triethanolamine-tea/

“In products intended for prolonged contact with the skin, the concentration of TEA should not exceed 5%.”

“TEA is lumped in with some other ingredients that have earned it the warning, “should not be used in products containing N-nitrosating agents to prevent the formation of nitrosamines.”  However, because TEA is a tertiary amine, it does not react with nitrosating agents to produce nitrosamines.  Using very sensitive analytical tools, a study by the Regulatory Toxicology and Pharmacology found when TEA was ingested with sodium nitrite, no significant nitrosamine formation was found.”

I do not know how reliable the site is, but I do see different “organisations” have different maximum usage rate of certain or all chemicals. And I agree that “testings” done on animals and humans are distorted. SLS for example, are tested by using patch, stuck on skin for 24 hours. Who the f**k in real-life leaves soap or detergent 24 hours on their skin! Water is poisonous and proven to have had killed people, it also strips lipids and water-soluble substances from skin making skin unnaturally dry, so why bother drinking and using it!

After looking at lots of stoichiometry, Triethanolamine simply can NOT be reduced. It can be reduced only with certain acids, such as Citric Acid releasing H2O, which is called “condensation reaction” (bloody fancy word that I learnt!). With Gluconic Acid, no H2O is released, hence no condensation reaction. No wonder the total molecular weight is massive, a combination of both Triethanolamine AND the said acid/s, compared to the same acid/s that are mixed with NaOh or NaHCO3!

Triethanolamine is not a conventional base that schools teach us, That is, must be some reaction (fizzes) to be valid. I never see fizzing mixing Triethanolamine with acids. Still waters run deep, perhaps…ummm.

[Cst4Ms4Tmps4]

@Pharma

All right. Your short answer for now is accepted. I will tell you my story.

I think the calculated numbers are too high. No wonder it was extremely tacky!  :tongue:

I made Propylene Glycol out of commission. I do not know why the said mixtures are often tacky. You did not mention their concentration used that makes them tacky. My educated guess is the more Hydroxyl units the more tacky it is. Glycerin (3 hydroxyl units) is loads more tacky than Propylene Glycol (2 hydroxyl units).

I know that Urea will not work well without enough moisture that is the reason why I out in high amount of Propylene Glycol (20% is still much less tacky than 2% Glycerin if used alone. Weird).

I also dropped Urea to 10%. Does not change the initial tackiness (Not sure why. Sort of like a ritual. Must be is the humidity). About 6 minutes and beyond, tackiness is very little to none, the longer the more undetectable it becomes. Observed timing is here, uncontrolled environment, high humidity. In an air-conditioned room it was like nothing.

Armed with new knowledge I ought not worry not enough humectant. I learnt that salts are the most-cost effective humectants and are not tacky (if used with care) compared to polyols and possibly diols as well. No wonder why some literature state that adding tiny amount of NaCl can enhance Urea. They do not mention ‘enhance’ how though. I now know, I think I know the reason now.

I also take your advice very seriously that pH is more important than buffer strength. I randomly made up a very weak salt, so weak that it gives me a very comfortable non-tacky and moist sensation, much like Sodium Lactate only without the horrid scent of spoilt milk. Because it is very weak Carbomer is happy to have it. Still liquid-ish, although high yield value still present. I dare not add more than 0.5% Carbomer lest it be tacky.

I learnt something new during my frustrated moment. A few times I calculated to neutralise Citric Acid with Sodium Bicarbonate with good old reaction stoichiometry, that few times pH is already at about 6! No need extra step to first make Sodium Citrate and then add more Citric Acid to adjust pH!

I was frustrated because I could not find reliable source that teaches me how to mix both acid and base in one single step making the salt and required pH, rather than doing it separately (because I have no Sodium Citrate nor Sodium Gluconate). If you could share this one-step approach, please kindly share it with me. I will like, share, and subscribe to your channel. Oh, I will definitely turn on the notification bell.  :sweat_smile:

Henderson–Hasselbalch equation does not emphatically apply to base-acid neutralisation. It applies only to SALT and its acid/base. I do not know why some people suggest the equation. Maybe they don’t know any better.

On the other hand, Gluconic Acid is neutralised at pH 7 again and again.

What is going on? Something to do with Citric Acid’s dissociative identity disorder having three pKa? Please do not tell me again that triple acid is impossible. I know you can do it!  :tongue: No calculation required for this.

Initially, I thought salts’ pH follow their acid’s pKa. Then, I thought Citric Acid has three pKa, it is only natural it is pH 6.39 and because it takes 3 molecules of Sodium Bicarbonate making Trisodium and therefore inherently chose the 3rd pKa which is 6.39. If it is Disodium then it is pH 4.76. If Monosodium then it is pH 3.13. Go ahead and laugh at my expense! 😉

After analysing long and hard, looking at Sodium Chloride, Sodium Gluconate, and other salts, their pH is not truly 7 but between 6.5 and 9. And then the knowledge that there is such thing as ‘acidic buffer’ AND ‘alkaline buffer’, that makes whatever I learnt about neutralisation went down the drain. Can’t trust text books! This is the reason why science keeps me interested and curious! Science is about knowing, learning, and it works, what works and what doesn’t work, does not require anybody to believe.

I read and read your bees, party, girls, honey, flower field story again and again, repeatedly like a broken record in my bloody head. I sincerely and genuinely want to understand how the world works! I am not the type of half arse who gets answers, does it, goes to bed soundly, not bovvered, and case closed.

I ‘kinda’ ‘finally’ ‘get it’. Correct me if I am incorrect-

1) Urea is a species which is sensitive to high pH. Specifically higher than pH 6.2. Specifically it is Ammonia that is sensitive to high pH. 

2) If Ammonia detects above pH 6.2 nuclear fission happens.

3) Below pH 6.2 nuclear fission also happens.

4) As long as pH is maintained at ±6.2 Ammonia stays in its ivory tower and happily allows the rest to rule Camelot however their heart’s delight to their heart’s content.

5) pH perfect at 6.2 still does not stop Urea from degradation. 

6) No matter how strong or how many glue traps (buffer and buffer strength) there are, Urea is predisposed to churn out bees (Ammonia).

I had already fully understood that all things, not limited to Urea, are decaying, nothing can stop the process. Even diamond degrades at atomic level. The reason is atoms keep moving, they rub into each other; friction is the destructive force. Same principle as to why water is still evaporating (sublimates) at freezing temperatures no matter what our lousy science text books brainwash us to believe.

Perhaps my/our major concern with Urea is exploding containers and extremely undesirable acrid Ammonia scent. This is the sole reason why this drama is created.

7) Only at pH 6.2 will Urea churn bees out more slowly than other levels of pH. Just slow and steady, slowly but surely.

Wot! Science does not know why…More sleepless night and down the rabbit hole for me! LOL!

You wrote:

We want to know how many grams of urea correspond to how many grams of citric acid: 1/60.06*210.14=3.5 (rounded)
3 urea = 6 ammonia = 2 citric acids molecules: 3.5/3*2=2 2/3
In a 5% urea preparation of 100g are obviously 5 g urea and therefore 11.66 g of citric acid would be required.

I am a bit confused there as there is no label. I am mentally blind, you see.

- 3.5 is in gramme of Citric Acid. 1g Urea corresponds to 3.5g Citric Acid

- 3.5g Citric Acid ÷ 3 molecules of Urea x 2 molecules of Ammonia = 2.3333333g Citric Acid

- 5% Urea x 2.33333g Ctric Acid = 11.66g Citric Acid

Did I correctly understand you?

I detest mathematics. Without it I would be even more blind, ironically. I would be doing unnecessary trials, errors, and wastefulness. Before the maths I was doing by feel and by “what people/the Internet says”. I was indubitably an insignificant ignorant fool.

[Cst4Ms4Tmps4]

I forgot to say that I have 20% Urea in my formulation!

But that will change. I will reduce it to 10%. I find 20% is kind of tacky. There is nothing much on my list that is tacky.

Urea 20.000 %
Propanediol/Propylene Glycol 20.000 %

PQ-7 (~9.5% active) 2.000 %

Water q.s

(0.5% Carbomer)

I hope 0.13 M Citric-Citrate buffer could stabilise 10% or 20% properly. But for how long is debatable. Maybe the maths could predict something about it. Argh the maths again!

The amount of buffer cannot be too much. 1.5% or a bit more total Sodium Citrate appears to be the sweet spot. Otherwise it is Carbomer’s turn to be destabilised by the power of electrolyte.  What sort of juggling madness it is! I cannot win, can I!

I know there are ‘advanced’ stuff out there for everything. I simply cannot spend too much on those. They either do not exist in where I live (Malaysia), they must be purchased in large quantities, or exorbitant for me (I’m not doing a business to earning back my pennies). Oh you better believe me that I was and still am exceedingly frustrated trying very hard hunting for chemicals, which is the reason why I finally settled down and utilise very simple, common, cheap, and old school, but tried and true chemicals.

You may ask/wonder why 20% Urea (there is always somebody asking or wondering why someone uses this and why uses that). A few individuals had said that 30% is too high. I then reduced it to 20% and still too high. It is because I find that 20% works very on me.  Yes, on me and only me. I am not into profit, not yet, at least not now. No, I do not have dry crackling skin nor any skin diseases, just that high concentration of Urea seems to work well for and on me. No irritation whatsoever. Just me.

[Cst4Ms4Tmps4]

@Pharma
  I love the way you explain it!

I think you might have misunderstood my intention (or question). I do not mean to suck up all the products of Urea degradation! 145.75 grams of Citric Acid is insane!

To make the buffer with the same 145.75 grams, it will be 145.75 grams of Citric Acid monohydrate + 2247.1329 grams of Trisodium Citrate dihydrate. Oh yea, 2.2471329 kilograms. This makes 84 M buffer. 

I do know what buffer is for and I do know that its usage is very little. That’s why it is called buffer! However, I do not know the calculation and the deeper understanding of buffers, the mixes, the reactions and degradation, the explosiveness, and so on as you explained in frighteningly well and entertaining manner. (I darn sure keep this link for my future reference. I never let the effort of Tom, Dick, and Harry to go to waste, and then I ask the same bloody questions again and again the next time. I detest people doing that to me, thus I do my best not to do the same to others)

My plan is to utilise maximum amount of Sodium Citrate, at 1.5% or 3% because it seems all right with cheap lame electrolyte-intolerant Carbomer. I guess it is due to its high molecular weight compared to other salts (Sodium Lactate is the worst offender in my case. This is the very thing that made me disabled for a very long time, wasting time going natural only to fall back to Carbomer…once again). I compared them and the difference I noticed is their molecular weights. The maths could be correct about this.

At 1.5% Sodium Citrate-required Citric Acid will be 2.32%. This makes 0.13 M buffer.

I am using chart, guide, calculator! Because I am illiterate I had to go through Internet nonsense in order to find the correct and simplified ones. There are still certain things that I need to manually calculate.
For example is from w/v% to mol/L and from mol/L to w/v%. There is a calculator for it but is a bit troublesome that I need to click and click. Memorising simple MW of the acid and its salt and copy paste I can get the result quicker than I say Bob’s a salted fish. Do it repeatedly regurgitating 12 digits is nothing, until I calculate another chemical.

Another aspect that manual calculation is still needed is most, if not all, that I notice, calculators and guides do not factor in molecular weight.

About the formula part, I think it depends who is saying it. I see some use only ONE pKa of Citric Acid, there are also some use ALL pKa of Citric Acid to do the calculation. However, majority agree to pick the pKa nearest to the target pH that we want.

For my case…

1.5 % (Tri)sodium Citrate
= 15 g/L

15 g ÷ 294.1 MW of Trisodium Citrate = 0.051 mol/L

With the help of this I punch in pH=6.2, pKa=6.39, CB=0.051. Required weak acid is 0.07898964756453644 mol/L. It does not mention what sort of acid it is. Looks like I need to dig it up.

0.07898964756453644 mol/L x 210.138 MW of Citric Acid monohydrate = 16.59872655991655842872 g/L

16.59872655991655842872 g/L ÷ 10 = 1.659872655991655842872 %

1.66 % Citric Acid is to be added.

Total ‭0.13 M. Should be plenty much to stabilise Urea. For how long will this capacity last…I have not the slightest idea. I hope God of maths and future tells me. No body wants exploding tubes and bottles, this is what we care after all! No wonder many people moved away from using Urea due to its particular negative characteristic. I, for one, like Urea very much because it works extremely well and it is an inexpensive witchcraft.

By using this one as ‘second opinion’ and for fact-checking, both the calculations/results (or semi-automated) are nearly match made in heaven.

Please note that the input is:

CA c=0.07898964756453644 pKa=6.4

SC c=0.051 pkb=7.8

*****CA and SC do not matter. They can be anything. Do not have to be there. Only for reference. CA is Citric Acid. SC is Sodium Citrate. Only for my own reference*****

If all pKa of Citric Acid is used (replace pKa=6.4 with pKa1=3.13 pKa2=4.76 pKa3=6.39) pH becomes 3.34.

To further complicate things and if all 3 pKa are used, this may be appropriate. At the same 0.13 M and pH 6.2, Citric Acid (anhydrous) is 0.2256% and Sodium Citrate is 3.4777%.

I do not know which is more ‘correct’. One pKa or three pKa. What I know is three pKa requires significantly more Sodium Citrate than one pKa.

You mentioned about water activity, this is what I realised a long time ago. Urea, usually pharmaceutical, is in lipid; ointment. As you already know this greasy/oily is highly undesirable, lots of drag can make you apply even more than needed. This can be also another reason why people generally move away from using Urea, not away from ointment per se.

This article, page 129, states that it is preferable to prepare Urea containing preparations without buffer or acid, and use it fresh, use it within one month. This certainly is impractical and inconveniences the user and the maker. But of course in the article it mentions product amount is made just right for X amount of times and X amount of preparation to apply on which part of the body. Do you think humans are THAT consistent?  :p Not to mention there are people who want to save more money by stretching how long they can use a product, past best before date even!

[Cst4Ms4Tmps4]

@Dtdang

I cannot get the gist of what you meant by the “metal” or “alkaline” part. What you are trying to say seems fragmented. Did you mean the neutralisation?

If it is about neutralisation then alkaline is used to neutralise Carbomer. Carbomer per se is acidic, it will not fully swell. It swells best at around pH 7.

Personally, I find Carbomer is the best suspending agent (and thickener because it gels).
The only time we want to use some other thickeners and suspending agents (usually “natural” ones such as Xanthan Gum) is when the formulation has electrolytes/salts, subject to heat (like the tropical heat where I live), low or high pH.

Xanthan Gum is the best and the most natural thickener that I found. It has very high yield value, and is resistant to many things that Carbomer fails. This is assuming non-gel final product is not important because Xanthan Gum does not gel. I tried making it gel the way that I like but nothing make it gel as beautifully as Carbomer does. And assuming cloudiness does not matter (There are clear kind of Xanthan Gum. Mine is the regular cloudy kind).

The only drawback of Xanthan Gum is it can be tacky and slimy. I read somewhere in the Internet there are non-tacky and non-slimy types.

@Gunther

Oh yes! I did not see TEA-Carbomer, TEA-Acrylates, TEA-Salicylates! From A to Z!

Yeah. It appears that anything with TEA is dangerous. I think the reason is TEA is neither consumed in the neutralisation process, nor split into other un-dangerous components such as CO2 and H2O. TEA literally binds to acids as a whole.

[Cst4Ms4Tmps4]

@Bill_Toge 

I have just cracked the code to calculating how much an alkaliser is required to neutralise a given amount of Carbomer. The calculation is very easy! It is not as complicated as we thought it was! Acrylic Acid is the answer!

To make 1% Carbomer aqueous solution. Neutralised with Sodium Hydroxide-

1% Carbomer x 39.997 (MW of Sodium Hydroxide) / 72.063 (MW of Carbomer unit) x 0.7 = 0.389% of Sodium Hydroxide (70% neutralization)

Aligns with Lubrizol recommendation of 2.3% NaOH (18% active) to 1% Carbomer.

Calculated 2.3% of 18% NaOH is 0.414%.

To make 1% Carbomer aqueous solution. Neutralised with Triethanolamine-

1% Carbomer x 149.188 (MW of Triethanolamine) / 72.063 (MW of Carbomer unit) x 0.7 = 1.450% of Triethanolamine (70% neutralization)

Aligns with Lubrizol recommendation of 1.5% Triethanolamine (99% active) to 1% Carbomer.

---

On a different note, the European Commission Cosmetic ingredient database (CoSing) states that Triethanolamine of any kinds, its maximum concentration is 2.5% for leave-on products.

What if I want to use Triethanolamine to neutralise all acids including Carbomer, will the total content of Triethanolamine cause people to mutate into Super Villains?

My ‘new’ (partial) formulation is as follow:

0.725% TEA to neutralise 70% of Carbomer.

1.165% TEA to neutralise 100% Citric Acid (to make buffer).

1.141% TEA to neutralise 100% Glucono-delta Lactone (to make buffer).

Grand total of approximately 3.031% TEA.

As for the buffers, you may be wondering why 100% neutralisation. Just for the sake of calculation, looking at the worst-case scenario.

If all were 70% neutralised then the total TEA concentration is approximately 2.339%.

I know and understood from your explanation that Triethanolamine is something that we need not be frightened of. But is this ‘2.5% maximum’ a concern? Is it a valid concern? Another scaremonger?

---

Why Triethanolamine for all, you may ask. I was inspired as I was playing about with GdL and Sodium Lactate. 

Sodium Lactate is hopeless. Only very little (~1%) of it and 0.5% Carbomer is liquefied.
0.5% Carbomer surprisingly survives with the presence of 3% Sodium Gluconate. Not gel. Water consistency. Yield value is still incredibly high. Cannot suspend ball bearing or big bubbles but small bubbles are suspended.

This calculation could prove what is going on:

NaCl: MW 58.44

Sodium Lactate: MW 112.06

1% / MW 112.06 x MW58.44 = 0.52%

(1% Sodium Lactate is same mol % of 0.52% NaCl. And then refer to Lubrizol NaCl sensitivity chart) The higher the molecular weight of a salt, the less Carbomer will be affected.

Acids and Triethanolamine appear to be best friends as they are mutually stuck together. Literally fully combined. The molecular weight of the salt is literally two molecules combined. Nothing is lost like how NaOH would split to H2O, and NaHCO3 split to CO2 and H2O. 

---

If you wonder why do I need buffer…why all the convolution… It is because I have Urea in my formulation. To make matters worse, I fall back to using Carbomer, I have high temperature and high humidity issues, I have limited resources, I am not making things for profit, I am just a DIYer. All the ‘bad luck’ in a string. I gave up on Xanthan Gum and natural whatnot. I spent too much effort trying to “fix and make it better”  to no avail. Gradually makes no sense.

I will take your words at face value if you said 3.031% or more TEA is not an issue. I can sleep soundly. I trust that you never provide me with factoids. You know some stuff about the EU regulations, I should be fine.

[Cst4Ms4Tmps4]

@Pharma

Why, very informative! Looking at Phytic Acid’s molecular weight, I already fall in love with it! Its molecular weight is big AF! It is not something I could acquire, unfortunately. 

Sadly, there is no example of calculation. 

Do you mind showing just one calculation? Say, how much Citric-Citrate buffer to neutralise how much Urea. I guess it is Ammonia that is going to be neutralised, not Urea. 

Citric acid should be good as I need a sequester.  But like you said, use a mixture of two, three or more. The more the merrier by getting each of their different additional effects other than merely buffering.

Just one calculation. Just one example of the calculation. Pweety pwease. Your effort is certainly highly appreciated.

[Cst4Ms4Tmps4]

@Pharma Oh dear! It is 6.02 x 10^23? 

How do I calculate “2 molecules” of something capturing “1 or 3 molecules” of another thing without going through the insane equation? I believe there must be simplified version of it. Perhaps give some examples or tell me the name of it so that I can, hopefully, find online calculator for it.

The calculation for neutralisation does not seem to work. Maybe I do not know how to ‘twist’ it about. 

[Cst4Ms4Tmps4]

This post is apt!

I am not making any keratolytic product. No need for low pH.

I like to know how strong or what the capacity a buffer is required to stabilise a given amount of Urea? Is there a calculation for it? Let’s say I want to use:

a. Lactic-Lactate buffer

b. Citric-Citrate buffer

Is temperature factored in? I understood that Urea decomposes quicker as temperature rises.

Simplified calculations are appreciated. 

I read some articles including patents, they do not mention about how many grammes of buffer or acid is used. As if pH is the only thing that matters.

If pH is the only thing that matters then I guess 1% buffer would do, as long as pH is between 4 and 8 as @”DRBOB@VERDIENT.BIZ”  mentioned. 

In case you may wonder what my other ingredients are that may affect the total/final pH, please focus on only Water, Urea, and buffer. 

If you insist, my ‘secret’ is:

Urea 20.000 %
Propanediol 20.000 %

PQ-7 (~9.5% active) 2.000 %

Water q.s