Lcms 8045 triple quadrupole liquid chromatograph mass spectrometer

Analyses of piperazine derivatives were performed using the Shimadzu LCMS-8045 triple quadrupole liquid chromatograph mass spectrometer (LC-MS) equipped with a heated ESI probe or using high-performance liquid chromatography (HPLC) system Shimadzu-Nexera XR combined with SPD-M20A prominence photodiode array detector (DAD). Both systems were operated with LabSolution software. Common components of Shimadzu-Nexera XR HPLC were as follow: LC-20ADXR liquid chromatograph pump, SIL-20ACXR autosampler and CTO-20AC prominence column oven. The degassing units DGU-20A3R and DGU-20A5R were used, respectively.

The residue of the extracted RLs was dissolved and diluted in methanol to be analyzed by HPLC-MS. The analysis was performed using LCMS-8045 Triple Quadrupole Liquid Chromatograph Mass Spectrometer (LC–MS/MS, Nexera series, Shimadzu) equipped with a C18 reversed phase column (Waters UPLC, particle size of 1.7 microns). The detector was a LC-2030/2040 PDA Detector with an electrospray ionization interface (ESI). All RLs were detected in the negative ion mode producing [M–H]- pseudomolecular ions.
The analysis was carried out with a sample injection volume of 20 µL, mobile phase at a flow rate of 0.2 mL/min with a gradient of water (A): acetonitrile (B) (with 0.1% formic acid) from 10 to 95% in 28 min. The gradient was adjusted to 10% B from 0 to 2 min, increased to 90% B from 2 to 20 min and remained constant for 5 min at 90% B before it decreased to 10% in 2 min and remained constant for equilibration. The mass spectrometer was in the negative ESI mode and the scanning mass range was from 200 to 900 m/z (mass to charge ratio). RL congeners were identified based on m/z and their relative proportions were calculated using the obtained area for each congener of RL by HPLC–MS (Haba et al. 2014 (link); Zhao et al. 2019 (link)).