[Gunther]

Sodium Lauryl Ether Sulfate @ 30% concentration.

[Gunther]

ozgirl said:

In the current situation with corona virus the use of alcohol based hand sanitisers is preferred due to their effectiveness on this type of corona virus.

Benzalkonium Chloride is not recommended by the CDC for hand hygiene for this particular type of virus. https://www.cdc.gov/coronavirus/2019-ncov/hcp/hand-hygiene.html

I wonder if Benzalkonium chloride is actually effective against the novel coronavirus.

Read the study:

Persistence of coronaviruses on inanimate surfaces and their inactivation with biocidal agents

G. Kampf a, *, D. Todt b , S. Pfaender b , E. Steinmann b

[Gunther]

Menthol is not water soluble.
So you’d need either a semi-polar (co)solvent like alcohol, or an emulsifier.

[Gunther]

Most chemicals in fragrances are nonionic, thus they shouldn’t react with ionic surfactants.

At the end, you should test them yourself.
You can make a more concentrated solution to make any mild incompatibilities easier to spot.
You can also “incubate” them at higher than room temperatures to speed up the process.

[Gunther]

hobbiz said:

There is also an alternative to Ultrez 21, which is Ulcatrez 20 I think, same INCI.

Interesting.
What’s the manufacturer name for Ulcatrez?
(Google ain’t helping, it believes I’m looking for “Alcatraz”, not Ulcatrez, LOL)

[Gunther]

em88 said:

31ahmedazeem said:

i want to make hand senitizer But i dont know how much quantity % use of carbomer in water . and which is the best for it 940 or 980.

Based on your questions, you do not have enough experience in this area. I’d strongly recommend doing the sanitizer exactly as WHO mentions if you really must do it yourself. 

If you’re following the WHO guidelines, they clearly state that no thickener, or other ingredients must be added.

You can make sanitizer gel if you want, but it won’t follow the WHO guidelines.

[Gunther]

What was the formula you tried? (with percentages)

[Gunther]

amitvedakar said:

what about ETO sterilizaion? @Pharma . Sanitizer used to sterilize. Is it require to to sterilize it?

If it’s for medical or hospital use, then yes, it needs to be sterile.
There are some rare bacteria or spores that can survive, even inside 70% alcohol.

Pharma said:

If there’s no gelling agent, the right type/material of membrane will work well for alcoholic aqueous solutions. Question is rather, what ‘they’ understand with ‘sterile’. If they really mean sterile, you will have to use gamma irradiated containers which are then filled in a sterile/aseptic environment (for example using underpressure filtration through 0.2 or 0.45 um membranes directly into sterile bottles) and tightly sealed. By preference, you’ll using a pump system for the bottles with a sterile filter like those used for preservative-free eye drops to keep it sterile throughout usage period.

Which quantity are you intending to produce?

It will be a 1000 L batch.
Sterile filtered with a 0.22 um filter (they can be used either with positive pressure above, or with vacuum below).
As far as I know, 0.45 um filtering ain’t truly sterile.

The gamma irradiated bottles will be the hard part.
Hence why I was considering soaking them in glutaraldehyde solution and rinsing with sterile filtered water.

[Gunther]

These articles and studies suggest that a catalyst is needed for significant amounts of alcohol to by oxidized.

Ferric ions:
https://pubs.rsc.org/en/content/articlelanding/1967/j1/j19670001409#!divAbstract
https://www.tandfonline.com/doi/pdf/10.1080/17518253.2014.939721

Gamma irradiation:
https://www.nrcresearchpress.com/doi/pdf/10.1139/v70-441

Strong acid catalyst:
http://www.sciencemadness.org/talk/viewthread.php?tid=8661

triethyl({2,4,6-trimethyl-3,5-bis[(triethylazaniumyl)methyl]phenyl}methyl)azanium (tribromide)

based phosphotungstate complex (TBAP) catalyst:
http://www.arkat-usa.org/get-file/45161/

Light + enzymes:
https://pubs.acs.org/doi/pdf/10.1021/j150345a008

[Gunther]

Fekher said:

@Gunther I find lower level of Carbomer lower sticky effect, may you try the idea and watch. 

That definitly works, thank you. 
In fact we reduced the Carbopol content to make our last Carbopol Ultrez reserves last longer as it’s very hard to find.

It looks like a little Polyox might help reduce stickiness too. I’m still experimenting on that.

Any other ideas?

[Gunther]

Aculyn 38 and 88 work but viscosity is a bit low. The 88 has a slightly higher viscosity, but they also leave a sticky after feel.

[Gunther]

Belassi said:

You don’t need to sterilise containers that are filled with a sanitiser!

Well, it look like overkill but specs call for a sterile sanitizer.
(Mostly intended for medical/hospital use).

Some rare bacteria and spores can actually survive in sanitizer fluid, hence the specs to make it sterile.

Right now we’re disussing if we should sterile filter only the water, or the whole finished WHO/FDA/CDC based formula. I’m propossing to sterile filter the whole formula, to be on the safe side.

[Gunther]

joanaflores said:

em88 said:

I wrote the steps above. We registered a product with 70% m/m ethanol already.
Maybe you are looking for high viscosity gels? For me 6000-10000 cP is enough for a hand sanitizer. 

Hello, can you say how much triethanolamine do you use?

 I am using 0.35% carbopol 940.

When I add 0.17% triethanolamine, in the last half, it forms a milky mixture and it losses all viscosity.

I am concerned that this happens because I only have 20% m/m of water.

May I ask what alcohol are you using? ethyl or isopropyl
What’s the alcohol concentration in the gel?

I’m asking you because you can only make up to 60% alcohol using TEA (and that with Carbopol Ultrez, I don’t know if that works with 940)

To get beyond 60% alcohol, you’ll need some other neutralizers as stated in the Lubrizol document: Neutralizing Carbopol and Pemulen in Aqueous Hydroalcoholic Systems.

[Gunther]

Pharma said:

@Belassi You’re not going to kill spores with lavender EO. What you need is one or several of the following strategies:

- Use another oxidising agent: Iodine or hypochlorit comes to mind

- Cook the sh*ç@ out of your product (not to recommend with gels and alcoholic products, you know why better than I do :blush: )

- Use sterile filtration (not easy with gels and doesn’t solve container contamination and the like)

- Don’t care about spores (for more or less clean raw materials and GMP/GxP an acceptable decision)

- Use an aldehyde: Formaldehyde and glutaraldehyde are common but require uncomfortably high levels to go from sporistatic to sporicidal. As an educated guess, aldehyde containing EOs might be an option (unfortunately, that includes several of those which have to be labelled due to allergic potential exactly due to presence of reactive aldehydes).

The trick with spores is that they are very tough nuts to crack and require removal, heat (for some species even more than the product can take), or chemical reactions. Lavender EO contains mostly hydrocarbons as well as phenols and esters thereof which do not undergo necessary chemical reactions with spores. If you need inspiration which to choose, döTerra as an example has a list for possible candidates (first hit asking Google).

BTW go somewhat acidic (alkaline would work too but destroys the skin acid mantle and that’s obviously bad, worse regarding the current situation).

We are actually considering making a sterile filtered WHO formula based sanitizer.

I wonder what do we can do to sterilize the containers as they are not heat resistant thus not autoclaveable?
In fact, a proposed formulation will be sold in a spray bottle.

Soaking the bottles in a glutaraldehyde solution and then rinsing them looks like an interesting option.

[Gunther]

Graillotion said:

Gunther said:

Interesting because you can clearly tell the difference between cetyl and cetearyl (I haven’t tried Behenyl alcohol myself).
I believe the cetyl/cetearyl difference is that the former is more homogeneous than the later, so the crystal emulsion structure, hence the feel is different.

Just curious….which feel do you prefer….between cetyl and cetearyl?

I prefer cetyl as it has a more smooth feel.
But cetearyl emulsions are reportedly more stable.

You definitely need to buy small amounts of each one and try them both for yourself.
Experimenting is key to succeeding in cosmetic chemistry (and any chemistry field too). You can only get so far by reading without experimenting yourself.

[Gunther]

MurtazaHakim said:

It is difficult to find Pharmaceutical Grade IPA nowadays. Major producers of Hand Sanitizers prefer Ethanol 96% in producing hand sanitizers. Is there any specific reason for preferring Ethanol over IPA ???

Furthermore which global standards are applicable for efficacy testing of hand sanitizers or alcohol hand rubs ??? 

IMO IPA smells worse than ethanol does, thus a great reason to avoid the former and choose the later.

You don’t need ethanol 99.9%.
94 / 95% ethanol will do.
Pure ethanol is called ‘absolute alcohol’ is very expensive and readily absorbs water from air, becoming 95% ethanol.

Many alcoholic beverage distilleries sell lots of ethanol, but you often need a business registration (your local equivalent of DBA) to be able to directly buy alcohol from them.

[Gunther]

8% Aculyn Excel yields a low viscosity gel (too low for my taste), but the real problem is that it leaves a sticky afterfeel.

[Gunther]

Perry said:

I doubt you or your consumers are sensitive enough to notice any feel difference between Behenyl (C22) and Cetyl (C16).

Interesting because you can clearly tell the difference between cetyl and cetearyl (I haven’t tried Behenyl alcohol myself).
I believe the cetyl/cetearyl difference is that the former is more homogeneous than the later, so the crystal emulsion structure, hence the feel is different.

[Gunther]

5% Aculyn Excel (as is), yields a very low viscosity gel for both 60 and 70% alcohol test batches.
Just not thick enough for a sanitizer gel.

[Gunther]

Add the water soluble, non foaming ingredients first, i.e. EDTA tetrasodium, preservatives, etc

Predilute gel or thick liquid surfactants. i.e. predilute 70% SLES gel.

Premix surfactants with fragrance (if the fragrance is not water soluble or if you don’t use a fragrance solubilizer)

Add the thickeners as the last thing, i.e. CAPB
BTW why Guar gum? Why acrylates copolymer? You can simply use tiny amounts of salt to thicken it, given you already have CAPB.

Keep mixer rpm low.

[Gunther]

chickenskin said:

Good explanation.  I could see why people would think the v/v would equal w/w.  

Hydrogen Peroxide interacts with ethanol and partially inactivates the oxidative properties I thought.  

Nice Matt

At those low concentrations, Hydrogen Peroxide does NOT oxidize alcohol to an aldehyde or to a carboxylic acid.

I was concerned about oxidation too, but after reading some chemistry papers it looks like it doesn’t happen at such low H2O2 concentrations. At least not without a catalyst

[Gunther]

I have been rubbing my hands (and soak my facemask) with 3%  Hydrogen peroxide when returning home as a coronavirus prevention.

It hasn’t irritated my hands so far, but I quickly wash it off after drying, as it leaves a sticky afterfeel.

[Gunther]

What happens with BZK?
Does it precipitate out of solution?

[Gunther]

IMO cetyl alcohol are less “draggy”, but cetearyl alcohol emulsions are reportedly more stable.

[Gunther]

Belassi said:

At a guess, this:
Carbomer as I understand it, is acrylic acid. So when you neutralise it, you get a salt. In the case of the different bases, you’ll get, for instance, sodium acylate, potassium acrylate, and someone else will have to tell me what the rest are. And each salt will have a different solubility in alcohol.

That’s indeed the reason why.
Na, K salts are very water soluble but not too alcohol soluble, hence the need to use “exotic” neutralizers.

Salts are usually much less soluble in IPA than in ethanol.