Pharma
Forum Replies Created
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Yes it can but usually will not be transparent for obvious reasons unless you create a HIPE gel (check out Alchemy Ingredients), a microemulsion or a proper micellar suspension. Each comes with advantages and drawbacks.
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A buffer is only suitable +/- 1 unit around the pKa of the employed acid or base, respectively. Citrate for a pH of 5-5.5 is suitable.There are buffer tables readily available on the internet.The procedure would usually be to use citric acid and then adjust with NaOH.
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A buffer is chosen based on target pH. The required amount depends on the entire formulation or rather the compound which leads to pH shifts.If you want to have just a one fits it all, your disodium phosphate plus citric acid has a very broad buffering range and might be your best bet. However, it’s two polyprotic acids which may show incompatibilities in some formulations.
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Use sucragel instead of a polymer or go with a polymeric oil gellant and avoid water
.The instant you have an emulsion, transparency is lost unless you add a lot of polyols and other high optical density ingredients to the water phase. True microemulsions would also work for transparent emulsions. Whether or not these are feasible with polymeric gelling agents, I do not know. -
Hopefully not. It’s just the only sign for their presence a consumer can get
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Weird…Do a knock-out test.
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Hot process of menthol and methyl salicylate will simply tell everyone in the vicinity what you’re doing :smiley: . Loss isn’t much, though, and I would try incorporating into the oil phase and avoid PG.Essential oils and constituents thereof tend to show such a viscosity drop if added at high %. You could try a gelling agent and ‘cheat your way around it’.
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Try increasing glycerol. It will help with the 1388 and maybe with allantoin.But then again, it all depends on how much of what you have in your product .
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What’s the pH and did you put it (accidentally) in the fridge?Else, nothing suspicious.
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Depends what you have in your product. A low pH such as yours with proper preservation and not much bug food and no unsaturated fatty acids are usually not an issue.
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Buy thicker honey :smiley:
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I wouldn’t say it’s all in plane because there’s a stereocentre which can be inverted due to mesomeric effects. Amids show mesomeric stabilisation and have the equilibrium on the C=O double bond and C-N single bond (N in sp3) and not on the C-OH and C=N side (sp2) and the oxygen pulls on the nitrogen which reduces its nucleophilicity even further. I wouldn’t say that sp2 or sp3 are more or less reactive, it all depends on the compound (aromaticity), reaction type and, especially with nitrogen compounds, also solvatation and hence the used solvent.The one nitrogen you refer to is part of a substituted carbamide. Although carbamides can be brought to react this usually requires a fair bit of energy input and won’t happen in an aqueous solution at room temperature.The product of your proposition would be an imide-like compound (can’t find anything similar on Sigma Aldrich). Reactivity of carboxylic acids is poor especially if not present in their protonated form (low pH) whereas carbamides have pKb around 14 which would allow for a reaction at low pH (something not possible with amines). But I guess that the urea part would hydrolyse first.Maybe let it react with an activated carboxylic acid or at least a methyl ester?
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These two are ‘hyped’ because of biodegradability and being based mostly on renewable resources.Stearamidopropyl dimethylamine and the isostearate version (lower melting point) are not quaternary ammonium compounds and are not necessarily cationic surfactants, they only become such at low pH. This allows for a certain flexibility regarding combinations.Also, the incompatibility of QAC with anionic surfactants isn’t always visible if the ratio of one to the other is kept at >10 (or <1/10) but that’s just a rule of thumbs.
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Hi Mary,The fact that you re-post your request and that you didn’t answer my last mail tells me that it was too complicated and not the straight and simple answer you expected… that’s okay.I just wanted to point out that you, in this case, shouldn’t look for a formulator with a background in botanical and herbal medicine but just a formulator who knows how to add plant extracts into a standard formulation. There’s even no need for a pet product formulator since there’s no marked difference, just marketing.Like that, you’re going to find someone suitable way faster and with less wasted time for everyone.
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The amid group in allantoin will not react under normal conditions, let alone with a carboxylic acid
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Phytic acid works at bit better at lower pH than EDTA .EDTA works for Fe(III) but the instant you add a good antioxidant, you generate Fe(II) whose EDTA complexes dramatically lose stability below pH 4 and attain useless stability at pH 3.All/most other heavy metals one wants to chelate show similarly poor chelation at such a low pH.If memory serves me right, gluconic acid is also better at low pH.BTW do you really need a chelate?
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What’s the pH? If it’s below ~3, I’d say it’s allantoin which degrades.
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When do you have afternoon? It’s summer, so here in Switzerland we’re on Central European Time.
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Hmmm…. it’s a weird product since alginate mixed with calcium salts will instantaneously gel. Meaning that mixing pouch 1 with water wouldn’t create a gel weren’t it for the presence of xanthan and carbomer.Once you add gluconolactone, this one will gradually degrade to form gluconic acid and hence lowers pH. This in turn will render calcium alginate soluble and hence, de-gels alginate. The now more liquid product (I suppose it’s less of a gel than more of a suspension-like thing of tiny slimy grains) ‘frees’ magnesium carbonate precipitates. Once these precipitates are free, they get to react with gluconic acid to form CO2. This time delay allows for enough time to mix and results in a slow release of CO2. Without the slow release, you’d have an effervescent powder or acidulated mineral water.If you have the means to dry a liquid or wet powder, then I’d have an idea how to best prepare pouch 1. Without proper drying possibilities… it might get uncomfortable (either sticky lumps, alcohol vapours, or a too fast reaction upon mixing 1 with 2). During my studies, we still used to prepare effervescent powders for training (though they weren’t in use any longer) where we used anhydrous ethanol and let that evaporate over night. Not a wise idea without proper ventilation. Freeze or spray drying would be better.
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I thought oxygen was good for skin, cosmetic industry pushed that wisdom for a long time (maybe as early as the ’60, could that be?).Maybe I understand why CO2 should be good for skin: Oxygen = respiration = radicals and oxidative damage = ageing and problems. Block oxidative respiration with CO2 = problem solved. Putting a plastic bag over your head would do the same job for free and it could be re-used several times. Not by you and I’m not sure if someone else would want to use that bag after such a BS treatment (BS stands for Beauty Suffocation, the solution for all wrinkles, pale or grey skin tone, hair loss, and all other age related issues). :smiley:
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Primary or co-emulsifier .I like it though I have the impression that it tends to soaping (or lack the knowledge or silicones to avoid it).
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Looks like cultures of Serratia marcescens. Bon appetit!
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Is it the preservatives which cause the milky appearance? If so, upping pentanediol and/or glycerol to solve the issue would be a wiser strategy (from a theoretical point of view, not a consumer’s perception).
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YUMMY!*Hitting-LIKE-button-like-crazy*