vialroom

#coa-reading 2025-09-12

Friday11 messages3 participantstimes are UTC
Highlights from this day
  • ms_ms_mira — unrelated but water content is why an honest 10mg vial assays at 9.1. karl fischer titration, and most certificates omit it 21:12
  • ms_ms_mira — residual solvents matter more than people think for anything that went through a lot of purification steps 21:13
  • apob_over_ldl — net peptide is gross mass minus water minus counterion. that is why 11.4mg of powder can be a correct 10mg vial 21:16
MM
ms_ms_miralab20:48

unrelated but sterility and endotoxin are separate tests and almost nobody runs either on research material

MM
ms_ms_miralab21:07

two certificates from the same supplier have an identical chromatogram, is that normal

unrelated but water content is why an honest 10mg vial assays at 9.1. karl fischer titration, and most certificates omit it

residual solvents matter more than people think for anything that went through a lot of purification steps

👀8📉2

retention time shifts between runs are normal. relative retention time is the number to compare

AO
apob_over_ldl21:16

net peptide is gross mass minus water minus counterion. that is why 11.4mg of powder can be a correct 10mg vial

AO
apob_over_ldl21:29

nobody can authenticate a certificate from a scan. you authenticate the material by testing it yourself

*Janoshik not the other one

good certificate actually

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