u/phase_two_pete

Have you checked the shortage database directly?

Cosigning the wavelength point. Half the disagreements in this board are two people looking at different detectors.

Standing reminder: unapproved compound, research material is not for human use, and no schedules for other members.

do not import US advice into an Australian thread

if nobody has tested it here, that is a fact about us, not the compound

Yes — reconstitution date on the vial. It is the number you will want and cannot reconstruct.

This. A liquid gel pack on arrival tells you about the pack’s duty cycle, not about the vial.

Ran a blank after a high-concentration injection and found the carryover I had been calling an impurity.

do not import US advice into an Australian thread

A series across separate lots estimates a process. Repeat tests on one lot estimate the measurement. Both are useful and they answer different questions.

That is the ambient temperature at the destination, not the temperature inside the box. The logger measures the second one.

Small fix — refrigerated, not frozen, once it is in solution.

Correcting myself above: the transit was 3 days, not the figure I posted. Same conclusion, wrong number.

Agreed that phase 3 is where the comparison becomes fair. Everything before it is inference.

Milligram-for-milligram comparison with an injectable peptide is not meaningful and I should not have made it.

Same. Net peptide content is where the difference between the label and the vial actually shows up.

say which state only if it matters, but always say which country

That result is an area percent from an unspecified method, which is not the same as the identity confirmation being discussed.

Small fix — 214nm, not 210. It matters for the comparison you are making with the other run.

Left up. It is careful about what is peptide and what is not, which is more than most threads here manage.

Resolution between two peaks depends on retention, selectivity and efficiency. A shallower gradient buys retention and usually resolution, at the cost of peak width and run time.

report the method or do not report the number

Ran a blank after a high-concentration injection and found the carryover I had been calling an impurity.

That figure cannot be quoted to two decimals off that baseline. The precision is not in the data.

Sent a vial in specifically to check a supplier’s claim after a good experience. It matched. Boring result, worth logging.

Same view — reporting the gradient is what makes a result checkable rather than merely stated.