Spiking the sample with 1microgm/ml and sample volume was made 50ml. After doing solid phase extraction elution was done with 2ml of eluent and analysis was done with HPLC
You introduced in your column 50 mL containing 50 µg of your analyte. When you elute with 2 mL, if your recovery is 100 % you should found 50 µg in 2 mL. It means a concentration of 25 µg/mL. So the calculated % recovery is the concentration determined by HPLC divided by 25 µg/mL times 100. Regards.
Spike 1 microgram into a separate 2ml of the eluent.
Analyse both the sample that has been through SPE and the 'spiked' standard.
Directly compare the areas obtained
100 * Sample area/ standard area = recovery.
Repeat approx 6 times will give an estimated error of analysis
I assume that you took 1 ml of the 'spike solution to give a total of 1 microgram in your 50 mL sample. In which case the answer above should give you the estimate of recovery. Note that for some samples the flow rate trhough the SPE column can be critical to obtain maximum possible recoveries.
Hi,
You have an overview of the method recovery and matrix effect.
https://doi.org/10.1039/C9RA05301H
I hope this helps!