6460 tandem mass spectrometer

In this study, 1.4 mL polypropylene Matrix tubes and SepraSeal caps were purchased from Thermo Fisher Scientific and were used for frozen storage of dialyzed whole blood (DWB) matrix, DWB-derived quality control (QC) standards, and for the extraction of all study samples. Micrewtube^® tubes (2.0 mL) and caps were purchased from Simport (Montreal, QC, Canada) and were used for frozen storage of the calibration (calibrator) standard spiking solutions. Slide-A-Lyzer Dialysis Cassette G2 (10,000 MWCO; 15 mL capacity) from Thermo Fisher Scientific was used to dialyze lysed whole blood matrix. A Kinetex HILIC (100 × 2.1 mm, 1.7 µm particle size) analytical column from Phenomenex (Torrance, CA, USA) was used for chromatographic separation of ASNase PD markers. Chromatographic data were acquired using a 1290 Infinity Binary UHPLC system coupled to a 6460 tandem-mass spectrometer produced by Agilent Technologies (Santa Clara, CA, USA). MassHunter LC/MS Data Acquisition Software (Version B.06.00) was used for control and operation of the LC-MS/MS system, and MassHunter Quantitative Analysis Software (Version B.06.00) was used for chromatographic peak integration. Weighted (1/x) linear regression analysis for each calibration curve was performed using GraphPad Prism (Version 6.05) from GraphPad Software (La Jolla, CA, USA).

The identification and quantification of glucosinolates was conducted using ultra high-pressure liquid chromatography coupled to electrospray ionisation and a 6460 tandem mass spectrometer with triple quadrupole technology (UHPLC/MS/MS, Agilent Technologies, Waldron, Germany). The chromatographic separation was achieved by using a ZORBAX Eclipse Plus C18 (2.1 × 50 mm, 1.8 µm) (Agilent Technologies, Waldron, Germany) through a chromatographic gradient developed by applying different percentages of the solvents (A) 13 mM ammonium acetate pH 7 and (B) acetonitrile/formic acid (99.99:0.01, v/v), according to the multipurpose method optimised by Domínguez-Perles et al. [46 (link)], which separates intact glucosinolates, isothiocyanates, and their metabolites (Supplementary Table S1). The intact glucosinolates and isothiocyanates were identified following their MS2 fragmentation pattern [mass/charge (m/z) ratio] by applying positive or negative ionisation mode depending on the compound considered at the optima ESI conditions for the maximal detection of the analytes, and their retention time in comparison with authentic standards (Supplementary Table S2). The glucosinolate contents of the urine and plasma samples analysed were expressed as nanograms per mL (ng/mL).