Liquid liquid extraction procedure of rabeprazole

[anilray1155]

hi friends,

i am developed method rabeprazole using spe method but i want to develop for same analyte using LLE. I tried many of the method for LLE extraction after basifed sample.but here the problem of that inconsistency
in the result (Area responce). If you have some idea please inform me .
help me.
ThANKS.

[gbalock]

LLE is an excellent candidate for an internal standard. If the IS is chosen carefully, it can be added at the start of the extraction and the ratio of analyte to IS can be compared at the end of the analysis.
Good Luck,

[anilray1155]

yes ,i am allready tried LLE with IS
BUT HERE THE TWO PROBLEM OF THAT

1. AREA RATIO IS NOT CONSISTANCE
2.IF THE AREA LOSS IS MORE THAN SOME CRETERIA IS NOT VALID FOR GUIDELINE

SO PLEASE SUGGEST ME METHOD OR IDEA FOR CONSISTANCE RESULTS IN ANALYSIS OF RABEPRAZOLE

[elizabeth s]

Check the pKa of your analyte and the PH of the base you are using to basify you analyte is close therefore you have variability. Try to increase the volume of the base you are adding to your sample should be 2 pka above the pKa of the analyte.
or try 50:50 ethyl acetate: Hexan for extraction LLE.

Good Luck

[ym3142]

for me , I need detailed procedure to see where there be a problem.