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c/reconstitution·submitted 2 years ago by u/cesar_ivaturi

[Question] how do you actually verify mg/mL

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how do you actually verify mg/mL. I would rather ask a basic question now than get this wrong quietly for two months. Adding more water does not change how much peptide is in the vial. It changes the concentration, which changes the volume you draw for the same amount. That is the entire relationship. Bacteriostatic…

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8 comments, started 2 years ago
u/hedda_ekstrom154 points·2 years ago

more water is not more drug, it is the same drug in a bigger volume

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u/marta_weiss52 points·2 years ago

bacteriostatic water has the preservative, sterile water does not

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u/units_not_mgsyringe math43 points·2 years ago

Reconstituted at 1mL when I meant to use a different volume. Caught it because the units looked wrong on the barrel. Now I write 5mg/mL on the glass before I put the cap back.

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u/cesar_ivaturiOP34 points·2 years ago

Correcting myself above: I wrote the concentration the wrong way up. Mass over volume, not volume over mass.

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u/cesar_ivaturiOP17 points·2 years ago

What is written on the vial right now?

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u/rosa_mensah46 points·2 years ago

aim the stream at the glass wall, not at the cake

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u/RetaAndRegret289 points·2 years ago

Bacteriostatic or plain sterile water?

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u/elin_ferrari50 points·2 years ago

Correction: that gives 30 units, not what you have written. 15mg into 3mL is 5mg/mL and the division follows from there.

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