Volumetric dosing is a relatively easy way to accurately dose substances in the sub-milligram range. It involves dissolving a known quantity of a substance in a known quantity of liquid, from there it's very easy to find the concentration of the substance on a milliliter basis. You can use our tool to help create your solution here.
Some substances are active at sub-milligram doses. These types of chemicals require extreme precision that can't be achieved with consumer grade scales. Volumetric dosing is the only way to accurately dose the sub-milligram range in a safe and reliable manner.
There are 3 main reasons for volumetric dilution of a substance.
1) diluting a substance down to a safe range for use below the capacity of available scale.
2) diluting a substance down to a safe range below a threshold dosage to test for adverse reactions
3) diluting a substance down to a low micro gram dose to test that it is not a much more powerful substance then believed- ie , the recent bromo-dragonfly mislabeled as 2c-b-fly debacle.
- A good (milligram) scale
- a liquid measuring cup, graduated cylinder, syringe with ml markings or the like
- A small funnel
- Small glass bottles with eye dropper. Alternately use a measuring pipette.
- Liquid for dilution- ethanol, high proof alcohol, water
- Sharpie / permanent marker
- Research what your substance can be dissolved in, and at what concentrations. Some substances are not dissolved readily in water, and instead need a strong spirit such as propylene glycol or everclear. Sometimes, it is necessary to use a stronger solute when a higher concentration is desired.
- Take the substance you wish to dissolve, and weigh it with an accurate milligram scale. (Generally you measure out a substantial amount more than you intend on dosing, to increase the margin of error)
- Once you have a known quantity, you need to decide what concentration you want it. For example, if I have 100mg of a substance in powder, and I want 500µg in every milliliter of solute (A concentration of 500µg/ml) I would need 200mL of solute.
- The concentration can be calculated with the following formula
- quantity of substance / amount of solute = concentration.
- Ex. 100mg/200mL=500µg per ml
- Remember: The lower the concentration, the easier and safer it is to dose! Ensure your margin for error is as high as necessary.
When dealing with chemicals active in the sub milligram range, there is substantial risk of accidentally dosing oneself while working with the chemical. Necessary precautions must be taken to ensure safety.
- Gloves, dust mask, and eye protection are required
- Wipe down all surfaces as soon as you're done using them.
- Do not work with substances in an area with a breeze.
- Remember, just because you can't see it, does not mean it's not there. Chemicals active at quantities this low can be very hard for the human eye to detect.
- Absolutely do not touch your eyes, ears, nose, or mouth while working with powders.
- You should mark the bottles in some way- this avoids confusion while doing this and is vitally important if they are stored. You may think they will remember whats what, especially if there are differences in the bottles- but DON'T TRUST your memory!
- Cheap scales are not precise. Use extra caution. Likewise- kitchen measuring tools, cheap, student grade lab ware, eyedroppers- they are all less then 100% accurate. Err on the side of caution at all times.