[Mandy007]

MarkBroussard said:

@Mandy007

As long as you keep the temperature below 55C and Allantoin at or below 0.5% you will generally not get recrystallization.

Thank you. I will try as you suggested. 

[Mandy007]

MarkBroussard said:

@Mandy:

Two options:  (1) Heat the Allantoin + 1,3-Propanediol to 50C … should dissolve right away.  Or, as @ketchito mentioned, just add the Allantoin directly to the emulsion when it cools to 50C and homogenize.  The Allantoin will dissolve in the emulsion.

 If I heat the Allantoin in the 1,3 Propanediol, how do I avoid recrystallization ?  I know allantoin is famous for recrystallizing if heated hence why I have not tried any methods that require me to heat it. 

[Mandy007]

ketchito said:

@Mandy Did you try adding allantoin directly to the emulsion, during the cool down phase?

No I have not, I have always tried to dissolve it in a solvent first at room temperature then add it to the cool down phase.