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c/hplc·submitted 1 year ago by u/blunt_coldbox_2024

someone explain HPLC to me like I have not read a paper in years

Questionbranch of 7 comments

Trying to get a straight answer on this: someone explain HPLC to me like I have not read a paper in years. The system suitability argument, since it comes up whenever somebody posts a number without one. Before the sample result means anything, the instrument has to be shown to be fit that day: replicate injections…

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7 comments, started 1 year ago
u/liv_okafor787 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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[removed]290 points·1 year ago

[removed by moderator]

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u/yara_bakken237 points·1 year ago

you cannot report to two decimals off that baseline

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u/blunt_coldbox_2024OP205 points·1 year ago

Did you run a blank between injections?

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u/b12_baseline-34 points·1 year ago

retention time alone is not identity

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u/joaquin_petrov619 points·1 year ago

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

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u/medutest_mel332 points·1 year ago·edited

That is area percent, not mass percent. The trace cannot give you the second one.

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