Exion lctm

The LC–MS/MS analysis of 287 compounds was conducted using an AB SCIEX Triple Quad^TM 5500 coupled with an Exion LC^TM (SCIEX, Redwood City, CA, USA). A Halo C18 column (2.1 × 150 mm, particle size: 2.7 μm) was used for separating analytes at an oven temperature of 40 °C with two mobile phases consisting of (A) 0.1% formic acid and 5 mM ammonium formate in water and (B) 0.1% formic acid and 5 mM ammonium formate in methanol. A 20 min gradient was performed at a flow rate of 0.2 mL/min with 5% of the initial mobile phase B, which was held for 0.2 min, ramped to 50% for 0.3 min, increased linearly to 90% for 9 min, raised to 98% for 4 min, and then held at 98% for 3.5 min. To reach a mobile phase equilibrium condition, B was decreased to 5% for 0.1 min and held for 2.9 min. Under MS/MS conditions, the ESI positive and negative modes were employed for sample analysis. The pressures of the curtain gas, collision gas, nebulizer gas, and drying gas were 25, 10, 50, and 50 psi, respectively. The temperature of the ion source was 550 °C, and the positive and negative ion spray (IS) voltages were +5500 V and −4500 V, respectively. To achieve optimum sensitivity and selectivity, a scheduled multiple reaction monitoring mode was employed for all pesticides, and data processing was conducted using the MultiQuant^TM 3.0.2 software (version number: 3.0.8664.0, SCIEX).

Lipidomic analysis of the plasma sample extracts was performed using a targeted tandem mass spectrometry (MS/MS) approach using predefined multiple reaction monitoring (MRM) transitions (Sciex sMRM Pro Builder, Framingham, MA, USA) and in-house defined chromatographic retention time windows.
The analytical system consisted of a Sciex ExionLC ^TM coupled to a Triple Quadrupole Linear Ion Trap (QTRAP 6500+) (SCIEX, Concord, ON, Canada). Lipid metabolites were chromatographically separated using a Waters Acquity BEH C18 reverse phase column (1.7 µm, 100 × 2.1 mm particle size; Waters Corp., Milford, MA, USA), maintained at 60 °C.
The mobile phase consisted of water, acetonitrile and isopropanol (all Optima grade), which were all purchased from Thermo Fisher Scientific (Malaga, Western Australia). Mobile phase composition and gradients are described in detail in the Supplementary Materials, along with additional instrument settings. Specific MS settings, MRM transitions and chromatographic retention times for the lipids of interest are reported in the results section and Tables S2–S4 are included in Table S4.

High-performance liquid chromatography (HPLC) was carried out using a Sciex ExionLC^TM (Framingham, MA, USA) system equipped with two binary pumps, a solvent degasser, an autosampler with temperature control, a controller, and a column heater. Chromatographic separation of all of the analytes was performed using a Kinetex C18 column (100 × 3 mm, 2.6 µm particle size). The column temperature was maintained at 35 °C, and the injection volume was 20 µL. The autosampler temperature was set to 4 °C. The mobile phases were water (phase A) and methanol (phase B); both contained 0.1% formic acid and 2 mM ammonium formate. The LC pump was programmed at a flow rate of 0.5 mL/min, and the initial composition was 40% A and 60% B. A gradient elution was performed, where phase B was increased linearly to 90% in the first 7 min, and then it was maintained for 2 min. Finally, the gradient was returned to the initial composition, and the LC system was stabilized for 3.5 min before the next injection. The total run time was 13 min. A stock standard solution of each analyte was analyzed individually to determine its unique retention time.