By Anonymous on Tuesday, June 15, 2004 - 11:44 am:
Hi,
I work about drugs in HPLC.I generally use same concentrations for standard and sample but sometimes ý may not adjust exactly.
Is there a certain deviation between concentration of sample and standart?
Is there any reference about it?
Thanks for your time...
By Tim on Wednesday, June 16, 2004 - 06:05 am:
The acceptable differences between standard and sample concentration should be established when the method is validated. For main active content you would be looking at a range of 50 - 150% of the expected range. For degradate/impurity, you would need to go from 10% of your limit to 150% or more (or establish LOQ/LOD).