LC/MS/MS Analysis of Interacting Cardiac Drugs Digoxin, Quinidine, Amiodarone and Verapamil on Titan^™ C18

sample/matrix

Sample spiked into rat plasma

SPE well plate

HybridSPE^®-PLus 96-Well Plate (575659-U)

condition

100 uL of spiked rat plasma was added to the HybridSPE plate well, followed by 300 uL of protein precipitation solvent, acetonitrile with 1% formic acid. (The plate, sealed, secured on a vibrater, agitated by vibration at 1000 rpm for 2 min. The plate was transfered to a vacuum manifold. Vacuum was applied at 10 in Hg for 4 min.)

column

Titan C18, 5 cm x 2.1 mm I.D., 1.9 μm particles (577122-U)

mobile phase

[A] Water; [B] methanol, both with 0.1% formic acid/10 mM ammonium formate

gradient

0-1 min, 45%B; 1.5-4 min 90%B, 4.5-8 min 45%B 

flow rate

0.2 mL/min

pressure

2900 psi

column temp.

35 °C

detector

MS, ESI(+), MRM mode

injection

1 μL