If there is a G4 PAMAM dendrimer solution (in methanol), what are the suitable temperature, vacuum level, conditions, and time period for 5ml methanol removal from the solution using a rotary evaporator?
Also, are there any other simple techniques for its evaporation??
Dear Sara Hijazi, there is no general rule on the operating conditions of rotary evaporator, using rather practical skills. However, when microstructure is of concern, smooth and slow evaporation is to be followed (i.e., low temperature and pressure, at a prolonged time), harsh conditions induce irreversible microstructure alteration.
Freeze drying is another option, but for organic solvents, additional care is needed. Methanol is a low freezing solvent, so deep low vacuum and temperature are needed, thus may be a special freeze dryer is needed. My Regards
Dear Sara Hijazi ,
I recommend that the process be slow and at a low temperature. In addition to rotary evaporator, you also have the option of drying by nitrogen flow. Personally, this last option is more reliable, it is carried out at room temperature and it is much faster. Here is a link to the system that we have sometimes used in my lab:
https://m.made-in-china.com/product/Laboratory-Nitrogen-Evaporators-Price-with-Adjustable-Airflow-933994385.html
Best,
Fran
I would also consider using a lyophilizer - freeze drying under vacuum is very gentle.