number of injections for test preparations in assay analysis

[sathyanarayanan]

i have the following technical query, regarding the analysis of drug substances and products.,

as far as my understanding goes : WE PERFORM : “RESOLUTIONâ€

[tom jupille]

If the regulatory agencies say it's required, then it's required.

[DR]

Our practice:
We make several injections of 1 standard prep. at the start of the run to establish suitability with respect to %RSD.
If there is a resolution requiremnt involving a compound not normally found in the samples & standard, that's a single injection of another prep. before the standard injections. Tailing, theoretical plates etc. are generally taken from the first standard injection.
Generally, we do 3 additional standard injections after each bracket of no more than 12 samples.

If we're doing a standard curve instead of a single point (linrear through zero) calculation, replicate injections of the highest standard are made, then the rest of the curve and only the high standard is injected after each sample group.