Freezing aqueous solutions for long-term stability
I'd like to share a good method for weighing out and storing chemicals (like tryptamines and phenethylamines) in frozen solution. This method was devised by a professional chemist, and should allow samples to be stored for years without degradation. Many compounds are in fact stored in exactly this way in professional laboratories.
(I apologize if this post duplicates a previous post. This thread was just too impossibly big for me to read everything.)
Chemicals degrade in solution, but that process is almost nonexistent if the solution is FROZEN. (The chemical reactions we're concerned with generally take place in the liquid, or dissolved, state.) Therefore, try dissolving your compound in water (maybe with a little lemon juice or vitamin C to help it dissolve), pre-measuring appropriate amounts, and FREEZING the samples. It also won't hurt to keep them dark, but that's not usually a problem in a freezer.
What you need:
-- A scale (usually -- but see step 1)
-- A measuring syringe (you can also use 1 teaspoon = 5 mL)
-- Little containers for your frozen, dissolved samples
-- A freezer
Here's an example:
1) Weigh out 100 mg of sample. You don't need a milligram scale for this, but you do need a scale with a precision of 10 milligrams, i.e. 0.01 grams. These are widely available and relatively inexpensive. Using such a scale, your sample will weigh 100 mg +/- 10 mg. 10% precision is good enough for many purposes.
(Note: You can still use this method if your scale is less precise. Just use more sample. In fact, if you have no scale but you are sure you know the weight of your sample to start with, +/- 10%, you can just proceed by dissolving the entire sample.)
2) Dissolve the sample in a known amount of water. A little citric or ascorbic acid may help alakloids dissolve: lemonade isn't a bad solvent for many purposes. For simplicity, use a concentration you'll remember, like 1 mg/mL, i.e. 100 mg/100 mL. Now you have a solution of known strength. I strongly suggest either using the same strength for all your different chemicals, or writing the concentration on each and every container.
3) If you like, divide the solution up into parts according to how much of the chemical you need for each experiment. If you think you'll need 20 mg per experiment, make five 20 mL samples. A good way to store them is in little plastic amber pill bottles, the kind used at pharmacies. You can buy these at many drugstores or health food stores, or online. Otherwise, just freeze the whole solution -- one gram per liter, or whatever it is -- and thaw fully before using.
(Note: Make sure the caps seal well. Frozen solutions can "evaporate" (technical term: sublimate). If that happens, the chemical won't go away, but you might get confused if you decide to measure out only part of the solution later, since it will be more concentrated. This, among other reasons, is why an ice cube tray is probably a bad idea. But you could use an ice cube tray if you won't be dividing up samples after they thaw. Just be sure no one mistakenly puts one in their soda!)
4) Freeze the samples, being sure they remain upright and do not leak until they freeze solid. Keep them frozen. Thaw individual samples as needed, do experiments, and push back the horizons of knowledge. One tablespoon = 15 mL = 15 mg of sample from a 1 mg/mL solution.
NOTE: This method will ONLY work well for long-term storage if your samples FREEZE SOLID. Vodka will not freeze in an ordinary freezer. Chilld alcoholic samples will probably last awhile, certainly longer than room-temperature, but not nearly as long as frozen aqueous solutions.
A guy I know tried this with 4-HO-DiPT and said that the samples appeared to retain their potency for months, as expected with this method.
Chemicals won't last forever this way. Frozen food tastes bad after several years for a reason: reactions, including even slow degradation by bacteria, do take place. Just very, very slowly. I don't have the data for exactly how long tryptamines or PEA's should last in frozen solution. Use common sense and don't use a sample if it's become discolored, cloudy or developed particulate matter that you're sure wasn't there before.
By the way, I'm sure many of you have heard this before, but I'll just add it here. The general rule for storing any chemical is to keep it as cold, dry and dark as possible. When you're dealing with the actual chemical -- the powder, not dissolved in solution -- keep it sealed and stored in the freezer, or at least a cool dry place. If possible, store the sample container inside another container that has a desiccant pack. If you are getting out some frozen sample to use, let it first warm up to room temperature to avoid atmospheric moisture getting in.
Good luck. Do no harm. Do know harm.
Peace,
Dave