Bioequivalence and Bioavailability Forum • Spiking volume-total volume

Spiking volume-total volume [Bioanalytics]

posted by Ladi – Thailand, 2015-09-30 15:42 (3463 d 22:31 ago) – Posting: # 15498
Views: 6,985

Dear Ohlbe and other members,

Sorry to come back to this issue again but people at our lab are having problem with this idea (including our beloved QA).

❝ [...] we could use 500 uL of blank plasma and then spike with 20 uL or 50 uL of analyte solution. Then, what we should do is add 20 uL or 50 uL of diluent to all study samples too.

In my latest method SOP I stated that:

Cal curve, QC are prepared from 480 uL blank plasma and 20 uL spiking solution (in 50% methanol) before extraction.
To analyze study sample pipette 480 uL of the study sample and add 20 uL of 50% methanol before extraction.

The question people are having is should the drug concentration be calculated base on total volume of 480 uL or 500 uL?

I hope this question is not too silly,
Ladi

Complete thread:

spiked samples preparation Ladi 2015-09-17 07:04 [Bioanalytics]
- Spiking volume Ohlbe 2015-09-17 10:45
  - Spiking volume Ladi 2015-09-17 13:02
  - Spiking volume-total volumeLadi 2015-09-30 13:42
    - Spiking volume-total volume ElMaestro 2015-09-30 13:57
      - Spiking volume-total volume Ladi 2015-09-30 14:55