Bioequivalence and Bioavailability Forum • variation in response of the analyte and internal standard

variation in response of the analyte and internal standard [Bioanalytics]

posted by Helmut – Vienna, Austria, 2011-01-13 18:08 (5642 d 08:17 ago) – Posting: # 6411
Views: 5,767

Dear Hale!

❝ mobile phase: Acetonitrile: 10mM ammonium acetate:formic acid

❝ (50:50:0.530, v:v:v) pH: 4.6

❝ reconstitue solution: water+25mM ammonia+ACN (50:50), pH: 9.9

One thing comes into my mind: A different pH of the analyte's solution and the mobile phase may lead to instable conditions on top of the column. Do you have problems getting the extracts into solution? Maybe ultrasonification helps. IMHO it would be better to dissolve extracts in mobile phase - or even better a solvent with slighlty less organic modifier (results in narrower peaks).

—
Dif-tor heh smusma 🖖🏼 Довге життя Україна!
Helmut Schütz

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Complete thread:

variation in response of the analyte and internal standard haydonat 2011-01-13 10:27
- variation in response of the analyte and internal standardHelmut 2011-01-13 17:08
  - variation in response of the analyte and internal standard haydonat 2011-01-15 15:16
    - variation in response of the analyte and internal standard Ohlbe 2011-01-15 23:09
- variation in response of the analyte and internal standard Ohlbe 2011-01-13 19:14
  - variation in response of the analyte and internal standard haydonat 2011-01-15 15:22
- variation in response of the analyte and internal standard NewInPK 2011-02-01 18:32
  - variation in response of the analyte and internal standard Ohlbe 2011-02-02 10:22