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c/coa·submitted 2 years ago by u/freya_baptista

help me understand water content, I have read the wiki twice

Discussionbranch of 4 comments

I have had 10 orders now and I keep a table, so here is the honest summary rather than a vibe. Material has been consistent. Communication has not. Shipping has varied by about 40 days on nominally the same lane, which matters more in summer than in February. The independent number came back 99.0% against a claimed…

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4 comments, started 2 years ago
u/ismael_eriksen22 points·2 years ago

Yeah, 96.8% area is not the problem, the missing impurity breakdown is the problem.

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u/tove_ogunleye16 points·2 years ago

the counterion is part of the mass you paid for

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u/emil_agyeman14 points·2 years ago

The practical rule people converge on is 28 days at fridge temperature after first puncture, and that comes from the preservative, not the peptide.

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u/freya_baptistaOP5 points·2 years ago

The chromatogram trace is where the real information lives. The summary number is just a headline.

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How to read a certificate of analysis and what it does and does not tell you. Area% versus mass%, identity versus quantity, water content, related substances, acetate counterions, and the difference between a vendor-supplied COA and an independent test on the vial you actually received.

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