Lately, there has been some discussion about dosing drugs dissolved in a liquid by "drops", and whether the accuracy of this method is sufficient. See the DOC B&D for some of those posts.
Seeing as DOC is making the rounds again, an investigation of this matter seems timely, as many bluelighters will likely be seeking to accurately dose this compound, and will naturally choose liquid dosing.
Despite the claims of large variations between drops, in my tests, measuring by drop was accurate to +/- 10%, 15% when using poor technique. Many bluelight members describe measuring doses of as little as 20mg using one of the $20-40 0.001g portable scales - which are accurate to +/-5mg on a good day; making their doses accurate only to within +/- 25%!
So, contrary to the established wisdom, it would seem that measuring doses of a drug by counting drops is at least as accurate as other accepted methods of measuring doses. Of course, regardless of how consistently sized the drops are, this method is only as accurate as the measurement used when preparing the solution; It is never acceptable to trust that a sample from a vendor is of the promised weight.
There are two issues with liquid dosing.
The first is evaporation of the solvent. This always occurs, to varying extents, depending on the container, how well it's closed, and how it's stored. Vials containing drugs dissolved in liquid should always be stored upright. This also helps to prevent any loss of drugs (which can occur only if the liquid is in contact with the closure).
Despite these precautions, evaporation will always happen, potentially making the solution stronger than you expect. There is a simple solution to this. Affix an adhesive label to the vial, such that the edge of the label is straight up and down. When you prepare the solution, mark the level on the vial. After using some, mark the new level on the vial. Before using it, always check that the level is the same as it was, and if not, top it up with distilled water (or vodka, if using vodka or diluted vodka, which you should be, to prevent microbial action).
This method, if followed, will ensure that the liquid stays at the same concentration as it should be.
In the event of errors, such as forgetting to mark the new level, or allowing liquid to leak, as long as the liquid level is filled to the mark, it will never produce a solution stronger than expected, only weaker.
The second issue is dosing the liquid - one must be able to accurately measure the liquid. Obviously this isn't a problem when one uses a shot-glass sized amount of liquid for a dose. Most people would like to be able to keep their drugs in a vial, portable, and ready to dose by the drop. But is one drop always the same? Is it consistent enough to use for dosing?
The size of the drop is a function of the density, viscosity, and surface tension of the liquid (all functions of temperature), and the geometry of the dropper used.
So, let's pick out some droppers...
I'll be using the Specialty Bottle (specialtybottle .com) VC1D and VC4D products for this experiment (Vial, Clear, 1 dram w/Dropper, Vial, Clear, 4 dram w/Dropper). They are a useful supplier of equipment for independent researchers like us, as they have no minimum order.
The specific numbers will of course be different for different vials and droppers.
For each dropper, 10 drops were dispensed into a container on a Sartorius laboratory scale (0.0001 g resolution, ie, 0.1mg), and the mass recorded. At room temperature, 1mg of water is 1ul (micro-liter).
Obviously, you have to squeeze the dropper slowly with a more or less steady hand, if you just give it a generous squeeze, or shake while squeezing a drop out, you won't get accurately sized drops.
Results:
VC1D, H2O: 30.0-34.3 ul (avg 32ul, +/- 10%)
VC1D, 20% Ethanol* in Water (density 0.97)
20.1-23.6 ul (avg 21.8 +/- 10%)
VC1D, 40% Ethanol* in Water (density 0.93)
17.5-24.5 ul (avg 22.7 +/- 10%)
VC4D, H2O: 46.5-55.9ul (avg 50.7ul - +/-10%)
VC4D, 20% Ethanol* in Water
21-24.5 ul (avg 22.7 +/- 10%)
VC4D, 40% Ethanol* in Water
21-24.5 ul (avg 22.7 +/- 10%)
These results show that measuring by drops is accurate to about +/- 10%. That sounds bad, but it's is not bad - recall that people dose 2C's using $20 milligram scales, which are accurate to +/-5mg at best.
These tests also reveal a problem - the concentration of alcohol in the solution makes a HUGE difference. Because the alcohol would evaporate faster than the water, you should always replace evaporated solvent with everclear, to counteract this.
Since there is a greater variation between 0% alcohol and 20% alcohol than 20% and 40%, we can conclude that small differences in alcohol concentration make a bigger difference if the overall concentration is small. So given the choice, you should use 40% alcohol instead of 20% alcohol.
This problem with ethanol/water mixtures makes them a considerably less suitable option than they otherwise would be.
Bacteriostatic water would be a better choice. It contains benzyl alcohol as a preservative, and is safe for injection (ie, it's non-toxic), and the benzyl alcohol will evaporate much more slowly than the water, so the vial could be refilled using distilled water.
Poor Technique:
I attempted to simulate poor technique, by squeezing at uneven rate, or by simulating shaky hands. This resulted in an increase in variation between drops, but did not appear to produce a significant trend to larger or smaller drops. This implies that choosing a concentration such that a dose is several drops, instead of one drop, will improve overall dosing accuracy.
*Imperia Russian Vodka, diluted 1:1 with water for the 20% mixture. The concentration of alcohol in the vodka was not assayed.
Conclusion: How to dose by drop:
Always use the same dropper.
Choose a concentration such that 1 dose is more than 1 drop, to even out variation between drops.
Use distilled water, bacteriostatic water, or 40% ethanol in water. Bacteriostatic water is preferred.
Mark the liquid level on a dropper before you put it away to store it.
When you next use it, check the level, and make up for any lost volume, using:
Distilled water (if it's dissolved in water)
Everclear (if it's dissolved in alcohol/water mixture)
Drops vary +/- 10% drop-to-drop. This is better than using a $20 mg scale on a drug with a dose of less than 50mg or so!
My apologies for the wall of text. I swear, this started off as a short post!
Seeing as DOC is making the rounds again, an investigation of this matter seems timely, as many bluelighters will likely be seeking to accurately dose this compound, and will naturally choose liquid dosing.
Despite the claims of large variations between drops, in my tests, measuring by drop was accurate to +/- 10%, 15% when using poor technique. Many bluelight members describe measuring doses of as little as 20mg using one of the $20-40 0.001g portable scales - which are accurate to +/-5mg on a good day; making their doses accurate only to within +/- 25%!
So, contrary to the established wisdom, it would seem that measuring doses of a drug by counting drops is at least as accurate as other accepted methods of measuring doses. Of course, regardless of how consistently sized the drops are, this method is only as accurate as the measurement used when preparing the solution; It is never acceptable to trust that a sample from a vendor is of the promised weight.
There are two issues with liquid dosing.
The first is evaporation of the solvent. This always occurs, to varying extents, depending on the container, how well it's closed, and how it's stored. Vials containing drugs dissolved in liquid should always be stored upright. This also helps to prevent any loss of drugs (which can occur only if the liquid is in contact with the closure).
Despite these precautions, evaporation will always happen, potentially making the solution stronger than you expect. There is a simple solution to this. Affix an adhesive label to the vial, such that the edge of the label is straight up and down. When you prepare the solution, mark the level on the vial. After using some, mark the new level on the vial. Before using it, always check that the level is the same as it was, and if not, top it up with distilled water (or vodka, if using vodka or diluted vodka, which you should be, to prevent microbial action).
This method, if followed, will ensure that the liquid stays at the same concentration as it should be.
In the event of errors, such as forgetting to mark the new level, or allowing liquid to leak, as long as the liquid level is filled to the mark, it will never produce a solution stronger than expected, only weaker.
The second issue is dosing the liquid - one must be able to accurately measure the liquid. Obviously this isn't a problem when one uses a shot-glass sized amount of liquid for a dose. Most people would like to be able to keep their drugs in a vial, portable, and ready to dose by the drop. But is one drop always the same? Is it consistent enough to use for dosing?
The size of the drop is a function of the density, viscosity, and surface tension of the liquid (all functions of temperature), and the geometry of the dropper used.
So, let's pick out some droppers...
I'll be using the Specialty Bottle (specialtybottle .com) VC1D and VC4D products for this experiment (Vial, Clear, 1 dram w/Dropper, Vial, Clear, 4 dram w/Dropper). They are a useful supplier of equipment for independent researchers like us, as they have no minimum order.
The specific numbers will of course be different for different vials and droppers.
For each dropper, 10 drops were dispensed into a container on a Sartorius laboratory scale (0.0001 g resolution, ie, 0.1mg), and the mass recorded. At room temperature, 1mg of water is 1ul (micro-liter).
Obviously, you have to squeeze the dropper slowly with a more or less steady hand, if you just give it a generous squeeze, or shake while squeezing a drop out, you won't get accurately sized drops.
Results:
VC1D, H2O: 30.0-34.3 ul (avg 32ul, +/- 10%)
VC1D, 20% Ethanol* in Water (density 0.97)
20.1-23.6 ul (avg 21.8 +/- 10%)
VC1D, 40% Ethanol* in Water (density 0.93)
17.5-24.5 ul (avg 22.7 +/- 10%)
VC4D, H2O: 46.5-55.9ul (avg 50.7ul - +/-10%)
VC4D, 20% Ethanol* in Water
21-24.5 ul (avg 22.7 +/- 10%)
VC4D, 40% Ethanol* in Water
21-24.5 ul (avg 22.7 +/- 10%)
These results show that measuring by drops is accurate to about +/- 10%. That sounds bad, but it's is not bad - recall that people dose 2C's using $20 milligram scales, which are accurate to +/-5mg at best.
These tests also reveal a problem - the concentration of alcohol in the solution makes a HUGE difference. Because the alcohol would evaporate faster than the water, you should always replace evaporated solvent with everclear, to counteract this.
Since there is a greater variation between 0% alcohol and 20% alcohol than 20% and 40%, we can conclude that small differences in alcohol concentration make a bigger difference if the overall concentration is small. So given the choice, you should use 40% alcohol instead of 20% alcohol.
This problem with ethanol/water mixtures makes them a considerably less suitable option than they otherwise would be.
Bacteriostatic water would be a better choice. It contains benzyl alcohol as a preservative, and is safe for injection (ie, it's non-toxic), and the benzyl alcohol will evaporate much more slowly than the water, so the vial could be refilled using distilled water.
Poor Technique:
I attempted to simulate poor technique, by squeezing at uneven rate, or by simulating shaky hands. This resulted in an increase in variation between drops, but did not appear to produce a significant trend to larger or smaller drops. This implies that choosing a concentration such that a dose is several drops, instead of one drop, will improve overall dosing accuracy.
*Imperia Russian Vodka, diluted 1:1 with water for the 20% mixture. The concentration of alcohol in the vodka was not assayed.
Conclusion: How to dose by drop:
Always use the same dropper.
Choose a concentration such that 1 dose is more than 1 drop, to even out variation between drops.
Use distilled water, bacteriostatic water, or 40% ethanol in water. Bacteriostatic water is preferred.
Mark the liquid level on a dropper before you put it away to store it.
When you next use it, check the level, and make up for any lost volume, using:
Distilled water (if it's dissolved in water)
Everclear (if it's dissolved in alcohol/water mixture)
Drops vary +/- 10% drop-to-drop. This is better than using a $20 mg scale on a drug with a dose of less than 50mg or so!
My apologies for the wall of text. I swear, this started off as a short post!
