i asked a supplier for the gradient and got

i ask for the raw trace rather than the summary now, because the summary has already made the judgement calls, area percent, not mass percent

update as promised a certificate with a number and no chromatogram is asking you to trust the integration you cannot see, that was 2024 though

analytically speaking a broad late peak is usually something more hydrophobic than the target and it is usually small, that is a chromatography answer, not a vendor one

no axes, no reading it

you need more sample for identity than for purity. plan for that when you post it

a shoulder is unresolved, not absent. a shallower gradient will usually pull it out, integration is a judgement call

post the axes

explains two points

small point on integration a single injection is normal for a routine assay and triplicate is what you ask for when the number matters, area percent, not mass fraction

deconvolution is arithmetic

integration choices move the number by a few tenths easily. that is most of your inter-lab variance, that is a chromatography answer, not a vendor one