I’ve just joined and wanted to say Hi!
I’ve been a big fan of this website for a long time and (whilst lurking) have learnt such a lot here.
Now I feel it is only right for me to come forward and hopefully make a useful contribution.
I’ve been ‘playing around’ with a sublingual rapamycin formulation.
I wanted access to rapamycin powder that I know is authentic and is relatively free of excipients. Unfortunately since my redundancy/retirement I no longer have access to my HPLC-MS & GLC machines so am unable to do the analysis. So I have decided to extract it from a couple of tablets.
Using the table below I decided to use acetone as an extraction solvent since rapamycin is highly soluble in it (20mg/ml) and most excipients are not.
These are the steps I used to extract rapamycin
Grind up 2x 1mg tabs using agate mortar and pestle
Transfer powder to 1.5ml eppendorf tube along with 10x 2mm zirconia grinding beads
Add 1ml acetone (AR grade)
Vortex mix for 30 seconds
Centrifuge for 5 mins
Extract supernatent and decant to second eppendorf which is then placed on a dry heating block (~40C) with an air current blowing across it to aid evaporation
Add 1ml acetone to pellet in first eppendorf and resuspend using vortex mixer.
Centrifuge and decant supernatent into the eppendorf that has been on the hot block.
In total I did a total of 4 extractions (probably overkill) and ended up with a pale yellow pellet.
For the formulation, I made a Transcutol, propylene glycol, 37% ethanol solution at a ratio of 2:3:5
I added 250ul of this stock to the eppendorf and placed it in a 37C water bath for 2 hours with frequent vortex mixing to ensure solubilisation.
I then added 5ul of green food colouring (optional) so I could judge if the dosing solution was pooling at the base of the tongue, which would mean I’m adding it too fast.
To dose you touch your tongue against the roof of your mouth and with your head slightly back add rapamycin solution drop-wise on either side of frenulum where sublingual veins show. Alternate drops on either side of frenulum and allow time for drops to be absorbed