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c/hplc·submitted 1 year ago by u/hamza_weiss

[Lab] CPC cagri — Janoshik came back 98.1% against a claimed 97.5%

Labbranch of 7 comments

CPC cagri — Janoshik came back 98.1% against a claimed 97.5%. One vial, one service, one member paying, which is the only kind of result this board should treat as evidence. 98.1% and 97.5% — those are the numbers, and they are the ones I am willing to defend. Retention time shifted 0.4 minutes and I assumed the…

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7 comments, started 1 year ago
u/samir_falk177 points·1 year ago·edited

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.

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u/nabila_espinoza59 points·1 year ago

Started reporting my own integrations with the baseline choice stated. Arguments in my threads dropped by about half.

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u/honest_syringe_202546 points·1 year ago·edited

integration decisions move the number more than the sample does

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u/rania_okonkwo11 points·1 year ago·edited

Yes — system suitability first. Without it the number is an assertion about the instrument, not the sample.

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u/runa_cabrera40 points·1 year ago

Right. And a blank between injections settles the carryover argument before it starts.

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u/downvote_magnet102 points·1 year ago·edited

How old is the column and roughly how many injections has it seen?

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u/hamza_weissOP62 points·1 year ago·edited

What wavelength, and what was the gradient?

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