kratomiter - 1-10-2013 at 05:47
Hi!
I am conducting the first attempts to isolate Mitragyna Speciosa (Kratom) alkaloids using a strong cation-exchange resin. I've had good results but
can be improved, sure.
This is my experimental protocol:
1- I boiled 50 g Kratom leaves in 1L 5% acetic acid.
2- Filtration.
3- Passing the solution through a column filled with around 500 g SCX resin.
4- Washing the column with distilled water.
5- I use 1L 10 % NaCl as a stripping solution.
6- Now, I add enough 4% ammonia to the stripping solution until it turns brown (almost all mitragynine should be in base form at pH 10 or higher).
7- Let precipitate (usually it takes for me around 24 hours).
8- Filtration, I used a standard lab filter (pore size ~15 um).
9- Now I wash the filtered brown powder with distilled water and let it dry in oven at 60ºC.
Almost all protocols I've read use methanol with glacial acetic acid, is it much better?
How can I precipitated alkaloids faster? Also, I think there should be some protein contamination, but I'm not sure if there's an easy way to remove
it.
If anyone has experience with this kind of things, please post your tricks!
phlogiston - 1-10-2013 at 06:02
In what step is the MeOH + glacial acetic acid used?
If it is step 1, it also answers your protein contamination question, since most proteins are insoluble in methanol (in fact, methanol precipitation
is often used to deproteinize biological samples).
kratomiter - 1-10-2013 at 10:36
Thank you phlogiston. I don't use MeOH + glacial acetic acid, but I'll try next time (in step 1).
I have access to cheap methanol, but it has blue colorant so I'll try to get it lab grade.
kratomiter - 6-10-2013 at 14:39
BTW, a glass microfiber filter would be better for isolating alkaloids than standard lab paper filter, right?