Topic
Retention time
Why retention time is a hint and not a fingerprint, and what co-elution can hide behind a beautiful single peak.
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2024-05first seen
2026-06last seen
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retention_timebaseline drift on a gradient is normal. baseline drift on an isocratic hold is your column#hplc-massspec · 2024-05-25retention_timerelative retention time against a standard is comparable between labs. absolute minutes are not#hplc-massspec · 2024-05-25gradient_gregretention time shifts between runs are normal. relative retention time is the number to compare#coa-reading · 2024-07-14u100_patretention time shifts between runs are normal. relative retention time is the number to compare#coa-reading · 2024-08-18warsaw_vialyes, and the gradient#test-results · 2024-09-11blank_runthe retention time on this one is different from the last lot, problem#coa-reading · 2024-09-28half_life_halsingle wavelength detection can miss a co-eluting impurity that does not absorb there#coa-reading · 2024-09-28quiet.hoursshallow gradient#hplc-massspec · 2024-09-29quiet.hoursdo you trust an area percent from a shallow gradient ms/ms sequencing is the only thing i would call identity. everything else…#hplc-massspec · 2024-09-29HPLC_Hankrelative retention time against a standard is comparable between labs. absolute minutes are not#hplc-massspec · 2024-09-29bea_reconstitutesretention time shifts between runs are normal. relative retention time is the number to compare, i have it written down…#coa-reading · 2024-10-06deamidationretention time shifts between runs are normal. relative retention time is the number to compare#coa-reading · 2024-11-01cagri_curiousthats co-elution#hplc-massspec · 2024-11-05assay_not_purityretention time shifts between runs are normal. relative retention time is the number to compare#coa-reading · 2024-11-13void_volumeretention time is a hint, not a fingerprint. two different peptides can co-elute perfectly happily#hplc-massspec · 2024-11-17area_percentretention time is a hint#hplc-massspec · 2024-11-17triple_ag_tomthats co-elution#hplc-massspec · 2024-11-17rotate_the_siterelative retention time against a standard is comparable between labs. absolute minutes are not#hplc-massspec · 2024-11-17rotate_the_sitegenuine question does retention time on its own tell you what the compound is#hplc-massspec · 2024-11-17comment_fatiguethats co-elution#hplc-massspec · 2024-11-24apob_over_ldlshallow gradient#hplc-massspec · 2024-11-24hydrate_hanathats co-elution#hplc-massspec · 2024-12-08hydrate_hanahow do you tell co-elution from a clean single peak#hplc-massspec · 2024-12-08chlorhexsingle wavelength detection can miss a co-eluting impurity that does not absorb there#coa-reading · 2025-01-04abdo_two_inchretention time shifts between runs are normal. relative retention time is the number to compare#coa-reading · 2025-01-05reship_ritasingle wavelength detection can miss a co-eluting impurity that does not absorb there#coa-reading · 2025-01-05peak_splitsorry to jump in single wavelength detection can miss a co-eluting impurity that does not absorb there#coa-reading · 2025-01-13monoisotopicretention time is a hint#hplc-massspec · 2025-01-15low_and_slowshallow gradient#hplc-massspec · 2025-01-24blank_runbaseline drift on a gradient is normal. baseline drift on an isocratic hold is your column#hplc-massspec · 2025-01-24snac_and_waterdoes retention time on its own tell you what the compound is#hplc-massspec · 2025-01-25blank_runretention time is a hint#hplc-massspec · 2025-01-25area_percentretention time is a hint, not a fingerprint. two different peptides can co-elute perfectly happily#hplc-massspec · 2025-01-25night_pinhow do you tell co-elution from a clean single peak#hplc-massspec · 2025-01-25factory_direct_fibaseline drift on a gradient is normal. baseline drift on an isocratic hold is your column#hplc-massspec · 2025-01-25protein_floorsingle wavelength detection can miss a co-eluting impurity that does not absorb there#coa-reading · 2025-01-27void_volumethats co-elution#hplc-massspec · 2025-01-29pbs_pipwhats a normal gradient for a peptide this size#hplc-massspec · 2025-01-29bac_water_billsingle wavelength detection can miss a co-eluting impurity that does not absorb there#coa-reading · 2025-02-02electrolyte_eliretention time shifts between runs are normal. relative retention time is the number to compare#coa-reading · 2025-02-02ten_of_tensingle wavelength detection can miss a co-eluting impurity that does not absorb there, not advice obviously#coa-reading · 2025-02-03step_one_sianretention time shifts between runs are normal. relative retention time is the number to compare#coa-reading · 2025-02-09sunday_shotthats co-elution#hplc-massspec · 2025-02-09ms_ms_mirahow do you tell co-elution from a clean single peak#hplc-massspec · 2025-02-09void_volumeretention time is a hint, not a fingerprint. two different peptides can co-elute perfectly happily#hplc-massspec · 2025-02-09provincial_patdoes retention time on its own tell you what the compound is#hplc-massspec · 2025-02-09logrotatethe retention time on this one is different from the last lot, problem#coa-reading · 2025-02-14void_volumethats co-elution#hplc-massspec · 2025-02-15plus_sixteendo you trust an area percent from a shallow gradient#hplc-massspec · 2025-02-15void_volumewhats a normal gradient for a peptide this size#hplc-massspec · 2025-02-15void_volumeretention time is a hint#hplc-massspec · 2025-02-15two_lifts_a_weekbaseline drift on a gradient is normal. baseline drift on an isocratic hold is your column#hplc-massspec · 2025-02-15monoisotopicslightly off topic but baseline drift on a gradient is normal. baseline drift on an isocratic hold is your column#hplc-massspec · 2025-02-20vacuum_vicdoes retention time on its own tell you what the compound is#hplc-massspec · 2025-02-20gradient_gregslightly off topic but relative retention time against a standard is comparable between labs. absolute minutes are not#hplc-massspec · 2025-02-20karl_fischershallow gradient#hplc-massspec · 2025-02-24invoice_mismatchthats co-elution#hplc-massspec · 2025-02-24wrong_networkwhats a normal gradient for a peptide this size#hplc-massspec · 2025-02-24invoice_mismatchbaseline drift on a gradient is normal. baseline drift on an isocratic hold is your column, take that with a pinch of salt#hplc-massspec · 2025-02-24area_percentretention time is a hint#hplc-massspec · 2025-02-24