Agilent 1290 series liquid chromatography system

The analysis was performed on an Agilent 1290 series liquid chromatography system as previously reported (Liu et al. 2018 ) (Agilent Technologies, Palo Alto, CA) that included a binary pump, an on-line vacuum degasser, a surveyor autosampling system, a column temperature controller, and an Agilent 6460 triple-quadrupole mass spectrometer (Agilent Technologies, CA) with Turbo Ion spray, which is connected to the liquid chromatography system. The Agilent Mass Hunter version B 4.0 software (Agilent Technologies, CA) was used to control the equipment and for data acquisition. The chromatographic analysis of ALDP was performed on a Waters X-Bridge C18 column (3.0 × 100 mm, i.d.; 3.5 μm, USA) at room temperature. The mobile phase was water (containing 0.1% formic acid) and acetonitrile (30:70, v:v) at a flow rate of 0.4 ml/min.
The mass scan mode was a positive MRM mode. The precursor ion and product ion were m/z 559.2 → 440.2 for ALDP and m/z 419.9 → 199.4 for the simvastatin, respectively. The collision energy for ALDP and simvastatin were 30 and 25 eV, respectively. The MS/MS conditions were optimized as follows: fragmentor, 140 V; capillary voltage, 4 kV; nozzle voltage, 500 V; nebulizer gas pressure (N₂), 40 psig; drying gas flow (N₂), 10 l/min; gas temperature, 350 °C; sheath gas temperature, 400 °C; and sheath gas flow, 11 l/min.

The blood samples were collected after 0.5, 1, 2, 3, 6, 8, 12, 24, 36, and 48 h of dosing. The collected samples were centrifugated at 3500 rpm for 10 min to obtain the supernatant and stored at −80 °C for further analysis.
The plasma concentration of abemaciclib was analyzed by the LC-MS/MS method with the Agilent 1290 series liquid chromatography system and the Agilent 6460 triple-quadruple mass spectrometer (Agilent Technologies, USA). The reaction conditions were conducted according to previous reports (Naz et al. 2018 (link)). Briefly, the samples were separated on the C18 column with the mobile phase (0.1% formic acid in water: acetonitrile). The temperature of the column was 25 °C with a flowing rate of 0.4 mL/min and an injection volume of 5 μL. The MRM mode was conducted with the collision energy of 30 eV. The MS/MS conditions were as follows: fragmentor, 110 V; capillary voltage, 3.5 kV; nozzle voltage, 500 V; nebulizer gas pressure (N₂), 40 psig; drying gas flow (N₂), 10 L/min; gas temperature, 350 °C; sheath gas temperature, 400 °C; sheath gas flow, 11 L/min.
The pharmacokinetics of abemaciclib was evaluated with corresponding parameters, including the area under the curve (AUC), half-life (t_1/2), the maximum concentration (C_max), the time reached C_max (T_max), and the clearance rate (ClzF).

The analysis was performed on an Agilent 1290 series liquid chromatography system (Agilent Technologies, Palo Alto, CA, USA) that included a binary pump, an on-line vacuum degasser, a surveyor autosampling system, a column temperature controller and an Agilent 6460 triple-quadrupole mass spectrometer (Agilent Technologies, CA, USA) with Turbo Ion spray, which is connected to the liquid chromatography system. The Agilent MassHunter B 4.0 (Agilent Technologies, CA, USA) software was used to control the equipment and for data acquisition. The chromatographic analysis of AC was performed on a Waters X-Bridge C18 column (Milford, MA, USA) (3.0 × 100 mm, i.d.; 3.5 μm) at room temperature. The mobile phase was water (containing 0.1% formic acid) and acetonitrile (30:70, v:v) at a flow rate of 0.4 mL/min.
The mass scan mode was the positive MRM mode. The precursor ion and product ion were m/z 559.2 → 440.2 for AC and m/z 419.9 → 199.4 for the simvastatin, respectively. The collision energy for AC and simvastatin were 30 and 25 eV, respectively. The MS/MS conditions were optimized as follows: fragmentor, 140 V; capillary voltage, 4 kV; nozzle voltage, 500 V; nebulizer gas pressure (N₂), 40 psig; drying gas flow (N₂), 10 L/min; gas temperature, 350 °C; sheath gas temperature, 400 °C; and sheath gas flow, 11 L/min.