Antiseptic foaming solution

Tagged: antiseptic, formula, skincare-formula

Formulating

Antiseptic foaming solution

Posted by Batoul on August 1, 2021 at 9:12 am

Hello everyone.
I am formulating antiseptic foaming solution that contains hexamidine, chlorhexidine and p-cresol.
The solution is colorless and clear after preparing. However, it turned red and precipitated after after 2 days.

Can anyone help me?

I use propylene glycol to dissolve P-cresol and hexamidine.

Is it possible to use ethylene glycol to dissolve hexamidine and -cresol

I use Hydroxy Ethyl Cellulose to increase solution thickness.
I use cetrimide and tween-20 as soap base

I didn’t use anionic surfactant because of antiseptics incompatibility with anionic surfactant.

Any suggestions?
Thank you very much.

Batoul replied 3 years, 4 months ago 4 Members · 8 Replies
8 Replies

ketchito

Member
August 3, 2021 at 2:32 pm

@Batoul I’d make more tests, removing each ingredient to find out which one is causing trouble. The one I’d start with is p-cresol, since it’s one that could give that red color.
Batoul

Member
August 8, 2021 at 3:02 pm

Thanks @ketchito
I tried to remove ingredients and found that formula without hexamidine didn’t turned red.
The problem is I need to keep hexamidine since it is one of the active ingredients.
I have to find out what are the supposed reasons that could likely turn hexamidine red.

Do you have any suggestions to help?
ketchito

Member
August 9, 2021 at 12:29 pm

@Batoul Can you do another test, keeping the hexamide and removing one of the other ingredients? This could help you find the one hexamide is reacting with. After that, it’d be good to check if pH change prevents this reaction, so I’d use either a more acid or basic solution to see if that helps.
Batoul

Member
August 11, 2021 at 6:05 pm

@ketchito
Thank you very much
I will test it this way.
PhilGeis

Member
August 12, 2021 at 10:47 am

Why do you need Hexamidine? You’ve got two others
Raychemist

Member
August 12, 2021 at 11:02 pm

Hexamidine could be reacting with your Chlorhexidine. What are the percentages of each of the actives used in this formulation? Chlorhexidine is very sensitive to many other ingredients and using it will require you carefully consider the percentage concentration as compared to the other ingredients in the formulation
Batoul

Member
August 14, 2021 at 8:22 am

@Raychemist
I use
0.1% chlorhexidine
0.1% hexamidine
I add them separately.
Chlorhexidine is added early to the mixture
Hexamidine is added as lastly.
Raychemist

Member
August 24, 2021 at 9:26 pm

Kindly increase the percentage of the Chlorhexidine to 0.2%. Take out the Hexamidine totally from the formulation. Chlorhexidine is enough for your antispetic property in the formulation. I do hope this help resolve your problem.