Bioequivalence and Bioavailability Forum

Hi Bioanalytical,

❝ For a bio analytical method how relevant is the evaluation of dead volume or void volume

Interesting¹ but not relevant as long the method passes all criteria in method validation.

❝ For a method having very short retention time within void volume what should be the approach

All the usual stuff: Pumps and mixing systems with low volumes, low injection volume, narrow bore tubings as short as possible, correct column nuts and ferrules, clean frits, no dead volume on top of aged column(s)…

❝ Is it ok and should the evaluation of dead / void volume be ignored as it is estimated by LCMSMS technique

See above and this goody.²

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1. Hint: Thiourea SC(NH₂)₂ has practically no retention on reverse phase and can be used to estimate t₀ of the entire system (including the column).
   
2. Dolan JW. Extracolumn Effects. LCGC North America. 2008; 26(11): 1092–8. Open access.