Cornelius Krasel I thought so, but I was requested to ask :) Well at least I have a confirmation

Do you happen to know the highest purity possible to purchase and where? I read somewhere it can be above 90%

In addition of what is already said it is common to find producers selling glutaraldehyde in aqueous solutions ranging for a few percent up to 50% purity.

See for example: https://www.dow.com/microbial/glutaraldehyde/index.htm

In Science the common suppliers are:

Sigma-Aldrich

Fisher scientific

Acros organics

Perhaps the following link is of any use:

https://europepmc.org/articles/pmc4204927

Good luck with your search.