Recon calculator: 40mg in 5ml = 2.5mg/ml.
#reconstitution 2026-01-23
Friday42 messages11 participantstimes are UTC
Highlights from this day
- deadspace — this is the only table you need in your head 21:36
- pooled_sample — the reason people pick 2ml on a 10mg vial is exactly that column. every dose in the ladder lands on a whole mark 21:42
- VialBot — recon calc — 10 mg + 2.0 ml = 5.00 mg/ml. 0.25 mg = 5 u · 0.5 mg = 10 u · 1.0 mg = 20 u · 1.7 mg = 34 u · 2.4 mg = 48 u 21:50
- LC_MS_Lena — counterpoint to the always-dilute-more crowd. more diluent means a bigger volume under the skin and a longer sting 22:14
- deadspace — putting the general rule here so it stops getting retyped every week 23:16
dead space
fridge-thermometer.png
800 × 800 · 830 KB · not retained in the public archive
👀6
my rule is one concentration for everything so i never have to think about it at 7am, take that with a pinch of salt
update from 5 months ago: switched to a single concentration and have not miscalculated since
aim the diluent at the glass wall, not at the powder. it goes in gentler
update on the earlier thing gross powder mass is not net peptide. water and counterion are in that number
check your maths
do not add more bac water to an already reconstituted vial, you have lost track of the concentration
does benzyl alcohol matter if im finishing the vial in one go
read it at eye level
thats the vacuum
how do you all measure a half unit, or do you just not
im getting bubbles in the barrel every single time, what am i doing wrong
if the maths gives you 13.7 units, change the volume. do not try to hit 13.7
too dilute imo
yep 10 units
[edited]swirl it. do not shake it. the foam is denatured protein and you are not getting it back
can someone check my maths before i ruin a vial
10mg vial, i want to add 2ml. that gives me 5mg per ml?
yes. 10 divided by 2
and 0.25mg is then 0.05ml
yes. and on a u100 pin that is 5 units
why 5
u100 means 100 units to the millilitre. so one unit is 0.01ml. 0.05 divided by 0.01 is 5
this is the only table you need in your head
| Volume drawn | U-100 units | At 5 mg/ml that is |
|---|---|---|
| 0.01 ml | 1 | 0.05 mg |
| 0.05 ml | 5 | 0.25 mg |
| 0.10 ml | 10 | 0.5 mg |
| 0.20 ml | 20 | 1.0 mg |
| 0.34 ml | 34 | 1.7 mg |
| 0.48 ml | 48 | 2.4 mg |
| 1.00 ml | 100 | 5.0 mg |
📌7✅5
oh that clicks
the reason people pick 2ml on a 10mg vial is exactly that column. every dose in the ladder lands on a whole mark
same vial, three ways
10 mg vial, 0.25 mg starting dose
+1.0 ml = 10.0 mg/ml -> 0.025 ml -> 2.5 u
+2.0 ml = 5.0 mg/ml -> 0.050 ml -> 5 u
+2.5 ml = 4.0 mg/ml -> 0.0625 ml -> 6.25 u
same vial, same dose, three different things to read off a barrel6.25 units is where people start guessing, and the guessing is the whole problem
recon calc — 10 mg + 2.0 ml = 5.00 mg/ml. 0.25 mg = 5 u · 0.5 mg = 10 u · 1.0 mg = 20 u · 1.7 mg = 34 u · 2.4 mg = 48 u
the bot is doing it too, good
counterpoint to the always-dilute-more crowd. more diluent means a bigger volume under the skin and a longer sting
0.05ml you barely register. 0.4ml you will feel going in
and if you go to 1ml on a 10mg vial your dose is half a mark wide on the barrel. do not
so 2ml is the middle
2ml is the middle
putting the general rule here so it stops getting retyped every week
mixing tonight, will report back
*mixed. 5 units drawn, went in fine
and that was 0.05ml not 0.5ml, right
0.05. i triple checked
🎯4
honestly that is the whole skill