How to determine the presence of common impurities added for weight in psychoactive substances at home and with available reagents?
Preliminary tests- Inspect the structure of the powder under the magnifier. If the microcrystals vary in size and color, most likely the powder is multicomponent. With experience, it becomes clear even from high quality photo under zoom.
- Take 10-20 mg of powder (if there is no exact scale, then on the tip of a knife), put it in a glass vial (from antibiotics) and add 1 ml of water. Observe its dissolution. If the substance is in lumps, it may take some time (or heating the vial on the stove (just not to boiling), or in hot water). If after all the lumps have disintegrated some substance has not dissolved, and even more so if it precipitated or became jelly-like consistency when cooling, you definitely have impurities (microcrystalline cellulose - MCC (microcrystalline cellulose), silicon dioxide, inorganic salts).
- If everything is dissolved, you should measure the pH of the solution with a universal indicator. The value should be in the range from 5.5 to 7, if it is much less - there are organic powdery acids (ascorbic, citric, etc.), if it is more - organic powdery bases (Novocaine, Lidocaine, Caffeine, etc.). If the pH did not show extreme values, you can taste it on the tongue. The sweet taste points out powdered sugar.
Tablets containing MCC and/or silicon dioxide and/or calcium stearate are usually cheap non-encapsulated drugs that are economically feasible to use for PAS dilution (analgin, levamisole, etc.).
If the sample contains MCC, it will either not dissolve even when heated (if there is a lot of it) or will precipitate as characteristic filaments when cooled. Filtration of the cold solution will give a residue on the filter in the form of strands resembling chewed paper (which they are).
Put the dry baking soda on a plate. Add one drop of sample solution on soda. If a violent reaction with the release of carbon dioxide begins, acids are present in the sample.
Put the drop of sample solution on a plate. Add 2-3 drops of concentrated alkali solution and then add a drop of 5% iron (III) chloride solution. If the color changes to the blue-violet one, the caffeine or other alkaloids are present in the sample.
We will need a drop of concentrated sulfuric acid. It is possible to take an electrolyte in a car store and evaporate it up to 2-3 ml at 100-110 degrees (it takes 30-40 minutes).
Add 2-3 drops of concentrated sulfuric acid to a dry sample. If the charring occurs with the releasing of foul-smelling gas, sugars are present in the sample.
Add 1 ml of concentrated alkali and heat. Put the indicator paper strip on the edge of the glass. If the paper will turn blue color and you can smell ammonia, the piracetam is present in the sample.
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