[em88]

It depends on the carbomer type and what are you neutralizing with.
You should post the full formula if you need a specific help. 

[em88]

Pharma said:

em88 said:

…I think that 0.20% Sodium PCA and 0.30% Glucam P-20 are very low to actually have a noticeable effect. 

Regularly applying hand or barrier creams would be a more efficient way for people abusing or badly using hand sanitisers.

Exactly! People will wash their hands often anyway. In my opinion, there is no real reason to insist so much on adding humectants/emollients in sanitizer preparations. I’d use propylene glycol or 1,3 - propanediol and that would be enough. 

[em88]

You should keep the formulation as simple as possible unless you test your formulation efficacy. What’s the preservative doing there?  Tocopheryl is not needed. I think that 0.20% Sodium PCA and 0.30% Glucam P-20 are very low to actually have a noticeable effect. 

[em88]

Agate said:

We’ve already discussed this in the other thread, no? The issue that I see is that most spray bottles that consumer hand sanitizer is sold in do not dispense enough to achieve full coverage and sufficient contact time, within a reasonable amount of pumps.

What I’m arguing against is the misconception that liquid formulas automatically mean that it should be in a spray bottle, which is false. I’ve seen this perpetuated about a dozen times over the past month, and I’m getting a bit frustrated repeating myself.

(If anyone wants me to stop saying that sprays aren’t recommended, show me where the WHO says that spray bottles are appropriate for dispensing hand sanitizer, I couldn’t find it. If you can find such information I’ll apologize for my mistake and won’t mention it again. Until then, you’ll have to put up with me. )

My intention of asking was to see if you have any reliable source for that statement. I am open for new information and if the source is reliable I’ll take them in consideration.
Now, look at what I have found regarding this problem. 
“This policy does not apply to hand sanitizer gel or foam products because different or additional ingredients may impact the quality and potency of the product. This policy does not apply to aerosol sprays because aerosol sprays with propellent added to the formulation can result in altered potency of the finished hand sanitizer. Aerosol sprays with propellent outside of the formulation (bag on valve) may have safety and potency concerns due to the increased flammability risks of ethanol in an aerosol, risk of overspraying, variability of delivery of the product, rapid evaporation of alcohol, and inhalational toxicities.” source:FDA document Policy  for  Temporary Compounding  of  Certain Alcohol-Based  Hand Sanitizer Products  During  the Public  Health Emergency Immediately in Effect Guidance for Industry 

[em88]

Agate said:

The WHO formula should not be in a spray. It’s a dangerous way of application as you are guaranteed to achieve incomplete disinfection.

Why and how did you come up with this conclusion? 

[em88]

Giving too much information to patients will most likely end up with less information learned/memorized.
The same thing goes for all these methods of rubbing/washing your hands. In my opinion, these steps are only making something so easy (to rub/wash your hands) so hard and stressful. No one is going to memorize all those steps. Even if you apply all those steps rigorously, you will have a fairly good result but will have sterile hands. 
Regarding dosage, I don’t think there is any fixed quantity. It will strictly depend on patient to patient. The biggest difference is how big/small the hands are. 

[em88]

MarkBroussard said:

Perhaps there is a forest somewhere in all these trees!

The main issue is the contact time required for the alcohol to denature the viral proteins which is in the range 20 to 30 seconds.  It really does not matter if you use a spray or a gel.  Simply spray 1 pump wait 15 seconds, spray another pump.  Or, use a gel.

That is very correct. The contact time is very important and it is always considered as a factor in the efficacy test. 

[em88]

What people reproduce is a personal problem. Anyone can use what WHO recommended and replace anything with anything 

In my opinion, the biggest problems are: 
1. Offering untested formulations (like the link mentioned).
2. People without knowledge selling sanitizers to others.

[em88]

@lmosca and @Perry, I’m not saying anything about the person who did, whatever he did. There is a big issue in the video which is not taken into consideration, friction forces! It is supposed to rub your hands with the gel. By rubbing is usually meant to put some force, not just spreading the gel over the hands. While rubbing your hand with the gel, you destroy all kind of gel structures at the point that all the liquid (ethanol, water, and other polyols) are released from the gel structure and begins to evaporate. That is why at the end of the rubbing you are left with the sticky feeling since only the polymer is left on the hands.
Again, I would very strongly appreciate and use that knowledge if the test is actually done in comparison with the efficacy, not just by dropping some gel on the table, destroying the gel structure and say, “See? Now the ethanol is free from the gel.” 

@lmosca, one friendly suggestion. With all the respect, your posts are very wordy. Try reaching your point in fewer sentences. It will help readers very much. 

[em88]

DSTANK said:

Suitable for neutralizer 0.5% carbopol 980 in water. I wanted to understand why one is preferred over the other.

I see. There is an article from Lubrizol saying that there is a difference in terms of alcohol incorporation, and as I remember it correctly neutralizing carbomer with triethanolamine will incorporate more alcohol compared with NaOH solution. 

[em88]

Perry said:

@ngarayeva001 -  See this video explanation.
https://spark.adobe.com/video/XvyTzaDX0UiNp?w=_1397&fbclid=IwAR3PHCj64hEJjwyqrIRj6oSgPsaQLXo3wFskIRvnxeMKsx0wL56hbwb4nuk

That’s propaganda! It is not a reliable source of information. I was expecting an article comparing the efficacity of gels using different types of polymers. 
In my point of view, there is no release of ethanol by destroying the structure of the gel. It is like saying, you have to destabilize a cream to get the efficacy of the oils. 

[em88]

MurtazaHakim said:

According to CDC’s website, Benzalkonium Chloride is not an effective agent against SARS COVID-19. Most of the products mentioned on the provided link are based on Benzalkonium Chloride.

Secondly, in case of Sodium Hypochlorite and Hydrogen Peroxide, what concentration is to be used for formulating the final sprayable product ?

A registered biocide product we bought suggested a concentration of 1,25% active chlorine. Most likely the concentration is suggested based on tests.  

[em88]

In my country, it is regulated what denaturants to use in accordance with the finished product where denaturated ethanol is used. 
I’d suggest checking the regulations in your country. 

[em88]

What do you mean by best?

[em88]

You have to ask yourself since the beginning. Do you really need to have a gel?
If yes, xanthan gum can work. Still, don’t expect any good viscosity. You can use carbomer if you have. 
What is the reason of Aloe in your formulation? 
There is no need for glycerin as long as you have 1,3-Propanediol in your formulation.

[em88]

Jitendra said:

I want to formulate hand sanitizer with isopropyl alcohol and Carbopol 940. Pls suggest if these two are compatible with each other when triethanolamine is used as neutralizer.

How about not even trying? Or if you really must, follow what WHO is suggesting.

[em88]

The 63% w/w is correct and is used for ethanol 96%
I guess this percentage is very common for pharmacists worldwide. 🙂

[em88]

Fekher said:

@em88 actually increasing percentage of alcohol will make product more effective and for Coronavirus WHO says that product contains 80% Ethanol or 75% IPA. 

Exactly, you haven’t understood how alcohol works. 
There is a range of concentration where alcohol is more effective. 
I’d strongly suggest you read or use what WHO is suggesting!

[em88]

Pharma said:

Astonishing that we didn’t already have someone ask for colloidal silver against coronaviruses… there are so incredibly many people out there preaching shit they don’t know anything about and the brainless masses feed out of their hands, it’s scaring!

I’ve heard from folks using similar bogus and sometimes actually dangerous procedures (with hypochlorous acid or colloidal silver amongst other things) to treat diseases like common cold and even cancer. Fools!

Stupidity spreads way faster than viruses, and when we are in a pandemic situation it goes off the charts… 

[em88]

DavidW said:

Thanks everyone.  I thought the more PG I had the more “slip” and moisturizing it would be.  I took it out altogether and now I have very little sticky feeling.  Not sure why that happens though.  It is interesting.

Congrats! 

[em88]

Cafe33 said:

PG works as you described but in much smaller percentage. 1.5% was way too high. Somewhere around 0.3-0.4 % works well 

That’s way too low. 
3-5% is the right interval

[em88]

Carbomers can be used to make good gels with high concentrations of alcohol if the method is done right. 

[em88]

Thank you for the useful links! I am looking for authorized labs that can test biocide products. I’ll contact my local authority to see what/where do they suggest to get the tests done.

Thank you

[em88]

You should keep in mind that the viscosity will be pH sensitive. At pH 4-5 the viscosity will be higher compared to pH 6-7. 

[em88]

Belassi said:

The problem, Perry, is that we can’t carry a bathroom around with us…

what about not leaving the house?