Plate count

[rc_12321]

Hi evey body,

If plate count for a particular peak is , say,6000 what does it exactly mean?

[tom jupille]

It means that the baseline with of the peak is approximately equal to 5.2% of the retention time.

N = 16* (tR/wb)^2, therefore,

wb/tR = 4/SQRT(N)

[rc_12321]

How much % of Rt is generally preferred or acceptable?

[tom jupille]

No single/simple answer to that. It depends on the complexity and resolution of the sample. Probably around 1% generally, but may be down well below that for complex samples (e.g., tryptic maps). On the other hand several percent variation may be acceptable for something like a potency assay, where you essentially have only one peak. In essence, it has to be good enough that you can be sure that you are measuring what you think you're measuring.