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

bacteriostatic water — 16 things I got wrong before I got it right

Discussionbranch of 7 comments

Posting this as a discussion rather than a claim: bacteriostatic water — 16 things I got wrong before I got it right. Shook the first vial because nobody told me not to. It was fine, but I have swirled every one since. I keep a laminated card in the drawer with the arithmetic on it. Looks ridiculous. Has never once…

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7 comments, started 2 years ago
u/kenji_kimani107 points·2 years ago

Reconstituted at 2mL when I meant to use a different volume. Caught it because the units looked wrong on the barrel. Now I write 10mg/mL on the glass before I put the cap back.

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u/mateusz_achebe51 points·2 years ago

Careful — that arithmetic is wrong. 10mg in 2mL is 5mg/mL, so 0.5mg draws to 10 units, not what you wrote.

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u/india_generic_g14 points·2 years ago

do the arithmetic before you reconstitute, not while holding a syringe

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u/karl_fischer_kev0 points·2 years ago

Agreed — units are volume. Once that lands, the rest of the arithmetic is one division.

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u/erez_perrin1 point·2 years ago

swirl, never shake

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u/piotr_bruunOP1 point·2 years ago

Asked GGPeps what volume they reconstitute to for their own stability testing and they answered in one line. Useful thing to know.

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u/soren_zamora1 point·2 years ago

the powder cake sits at the bottom, the volume you add is the volume that counts

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