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

Spain: gradient, and what it actually costs here

Labbranch of 10 comments

Quick one. Canada here. gradient works very differently where I live than in the threads that dominate the front page, and I keep seeing people confidently given advice that simply does not apply outside the US. Specifics: the route I used took 5 weeks and cost roughly what I expected. The admin was worse than the…

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10 comments, started 1 year ago
u/marit_mensa1.8k points·1 year ago

Dead space in the needle hub holds a small but non-trivial volume. On low-volume draws that can be several units.

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u/rasmus_kimaniOP792 points·1 year ago

The PeptideMeter result being close to my own HPLC is the signal, not the absolute number. Both are right.

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u/sig_figs_sammod · analytical327 points·1 year ago

The PeptideMeter result being close to my own HPLC is the signal, not the absolute number.

Yes, exactly this, and it is the bit that took me 23 weeks to accept.

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u/rasmus_petrescu76 points·1 year ago

related substances are where the story lives, not the main peak

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u/mass_spec_maggieMOD1.1k points·1 year ago

This is an urgent-care question wearing a forum question's clothes. Please contact a clinician rather than waiting for replies.

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