6460 triple quad lc ms mass spectrometer

The LC-MS/MS analysis was performed using an Agilent Series 1290 UPLC system (Agilent Technologies, Waldbronn, Germany) coupled to a 6460 Triple Quad LC-MS mass spectrometer (Agilent Technologies, Santa Clara, USA). Chromatographic separation was achieved using an Agilent SB C18 (2.7 µm, 30 mm × 2.1 mm) at room temperature. The analysis was performed in the positive ion mode. The mobile phase A was 0.02% FA in water, and the mobile phase B was 0.02% FA in methanol with a flow rate of 0.3 mL/min. The elution gradient started with 10% of eluent B run at isocratic conditions for 1 min, and then, it was increased to 90% in 4 min and held for another 4 min. Finally, the initial condition was reached again in 1 min. The sample injection volume was set at 5 μL.
The mass spectrometer was equipped with an electrospray ion source. The following parameters were used: Q1 and Q3: set at unit resolution; the drying gas: 10 L/min, 350 °C; needle voltage: 4000 V; nebulizer pressure: 35 psi. The data were obtained and processed using the Agilent MassHunter Workstation Software (version B.06.00)
The precision and accuracy of the assay were determined using QC samples. The detailed validation procedures and acceptance criteria for the assay have been discussed in a number of studies^{31 (link), 49 (link)}.

The reagents and solvents were commercially available for analytical reagent (AR) grade and were used as received or were dried prior to use, as needed. The melting point was measured by X-5 binocular microscope melting point apparatus (Beijing Tech Instruments Co. Ltd., Beijing, China). Using dimethyl sulfoxide (DMSO-d₆) as solvent and tetramethylsilane (TMS) as the internal standard, ¹H-NMR spectra were recorded on 300 MHz and 600 MHz spectrometers and ¹³C-NMR spectra were recorded on 75 MHz and 151 MHz spectrometers (Bruker, Karlsruhe, Germany). MS data were obtained on the 7000C Triple Quad GC/MS and 6460 Triple Quad LC/MS Mass Spectrometers (Agilent Technologies, Santa Clara, CA, USA). Elemental analyses were determined on a Vario EL III elemental analyser (Elementar Analysensysteme GmbH, Frankfurt, Germany).