A solid-phase extraction procedure has been developed for the isolation of the adenosine A1 receptor agonist N6-cyclopentyladenosine from rat blood. The biological samples were spiked with N6-cyclopentyladenosine and the analogue N6-cyclohexladenosine (internal standard), diluted with sodium hydroxide, loaded onto disposable cartridges with subsequent desorption with methanol and analysis by HPLC. The performance of columns pre-packed with different C18-bonded silica phases or with a polymeric reversed-phase sorbent (Oasis HLB) was assessed. The highest extraction efficiencies (recovery rates\83.3%) for the two N6-alkyl substituted adenosines were achieved by the Oasis HLB cartridges. In addition, the polymeric sorbent provided reproducible recoveries (relative standard deviationB4.8%), whereas large variations (relative standard deviation values, 9–16.3%) in the extraction yields were observed using the conventional silica-based C18 cartridges. The described sample preparation method is rapid, simple, selective and it is suitable for pharmacokinetic studies.
Determination of the adenosine A1 agonist N6-cyclopentyladenosine in rat blood by solid-phase extraction and HPLC
SCALIA, Santo;DALPIAZ, Alessandro;
2001
Abstract
A solid-phase extraction procedure has been developed for the isolation of the adenosine A1 receptor agonist N6-cyclopentyladenosine from rat blood. The biological samples were spiked with N6-cyclopentyladenosine and the analogue N6-cyclohexladenosine (internal standard), diluted with sodium hydroxide, loaded onto disposable cartridges with subsequent desorption with methanol and analysis by HPLC. The performance of columns pre-packed with different C18-bonded silica phases or with a polymeric reversed-phase sorbent (Oasis HLB) was assessed. The highest extraction efficiencies (recovery rates\83.3%) for the two N6-alkyl substituted adenosines were achieved by the Oasis HLB cartridges. In addition, the polymeric sorbent provided reproducible recoveries (relative standard deviationB4.8%), whereas large variations (relative standard deviation values, 9–16.3%) in the extraction yields were observed using the conventional silica-based C18 cartridges. The described sample preparation method is rapid, simple, selective and it is suitable for pharmacokinetic studies.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.