Subject: Solvent Preparation and Dissolution of 7-hydroxymitragynine

Background:
I am working with 110 mg of 78% pure 7-hydroxymitragynine (7hm) (corresponding to 85.8 mg of active 7hm) and intend to dissolve it in a solvent mixture for volumetric dosing.

Solvent System:
I have prepared a solvent system consisting of:

• 5 mL of a 10% ethanol-water solution (with 0.5 mL ethanol and 4.5 mL water)
• 1 mL of propylene glycol

The total solvent volume is 6 mL. The approximate composition of the solvent mixture is as follows:

• Ethanol: 8.33%
• Water: 75.00%
• Propylene Glycol: 16.67%

Objective:
The goal is to dissolve the 85.8 mg of 7hm in this solvent system, while the remaining 22% impurity (~24.2 mg) is not required to dissolve for volumetric dosing.

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Questions:

1. Based on the solubility of 7hm, do you anticipate this solvent system (ethanol-water-propylene glycol) being effective for dissolving the desired amount of active 7hm at room temperature?
2. Would mild heating or additional solvent components be necessary to ensure complete dissolution, or is agitation (shaking/stirring) sufficient?
3. Are there any potential stability concerns or degradation risks for 7hm in this mixture?

I would appreciate your input on how this solvent system can be optimized or validated for reliable dissolution.