Thermo tsq quantum ultra

Samples collected 7 days after sham/SNI surgery were stored at −80°C until used. Neurotransmitter concentrations were assayed by Ultra-Performance Liquid Chromatography (UPLC) and Tandem mass spectrometry, as described in a recent publication (Huang et al., 2014 (link)). The LC system (Waters Acquity UPLC, Waters Co.) with a binary solvent manager, sample organizer, sample manager and column manager and a Waters Acquity UPLC HSS T3 1.8 μm column were used for the separation. The UPLC system was coupled to a triple-quadrupole mass spectrometer (Thermo TSQ Quantum Ultra), using ESI in positive mode. All data were processed by Waters MassLynx 4.0 and Thermo Xcaliber Software. Data were acquired and analyzed using Thermo LCquan 2.5 Software (Thermo Fisher Scientific).

Chlorambucil was quantified in dog plasma and urine by internal standardization, protein precipitation with acetone, and HPLC-MS/MS (Thermo TSQ Quantum Ultra, Thermo Scientific, Waltham, MA, USA). Chlorambucil and melphalan, the internal standard, were separated on a C18 4.6 X 100 mm column (Phenomenex Onyx Monolithic, Torrance, CA, USA) using a linear gradient mixing the mobile phases. Mobile phase A was acetonitrile: 0.1% formic acid (20:80, v/v) and mobile phase B was acetonitrile: 0.1% formic acid (80:20, v/v). The linear gradient started with 100% mobile phase A at the time of injection and was 100% mobile phase B at 6 minutes. The mass spectrometer utilized an electrospray ionization probe and was run in positive mode. The selected reaction monitoring (SRM) Q1/Q3 (m/z) transition for chlorambucil and melphalan was 305/169 and 306/247, respectively. The lower limit of quantification was 1 ng/mL using 100 μL plasma.