By Maneerat on Monday, August 18, 2003 - 11:06 pm:
Hello,i'm new in this forum.
I've been working for many days in a method development for isolate stavudine and lamivudine (antiretroviral) from blood plasma for pharmacokinetic study. We've tried with SPE technics using oasis HLB, conditioning with methanol, wash with ammonium acetate buffer pH 7.0. Eluting solvent we use 20% acetonitrile. Mobile phase contains phosphate buffer pH 6.9:acetonitrile(94:6). Retention time for stavudine is 10 min and lamivudine is 15 min. We're looking for suitable internal standard for this system.
By bill tindall on Thursday, August 21, 2003 - 06:49 pm:
It is not clear to me what you want the internal standard to do. Measure extraction efficiency, measure injection volumn, what? Once you decide what problem you want the internal standard to solve, choosing one will become more possssible.