QuaMeter produced metrics for 16 of the 17 electrospray instruments for Study 1 (ProteoWizard did not support centroiding algorithms for Waters instruments).
We automatically injected 0.1 ml samples onto a C-18 column (Nova-Pak C18, 3.9 mm × 150 mm, Waters Instruments, Rochester, NY).
The chromatographic apparatus consisted of a model 515 pump, a model 717 Plus autoinjector, and a model 2487 variable wavelength UV detector (Waters Instruments, USA) controlled by Empower software.
Mass spectra were acquired using the electrospray ionization in the negative ionization modes at fragmentation voltages of 175 V over the range of m/z 100 to 2000 on the UPLC-QQQ-MS/MS (Waters 2478, Waters Instruments) with drying gas flow of 12 L min−1, a drying gas temperature of 350°C, a nebulizer pressure of 35 psi, and capillary voltages of 3500 V.
HPLC analyses were performed on a Waters instrument consisting of a Waters 1525EF pump coupled with a Waters 2998 photodiode array detector and a Waters fraction collector III.
Gel permeation chromatography (GPC) measurements were carried out with a Waters instrument (515 HPLC pump) equipped with a Wyatt interferometric refractometer.
Analytical HPLC was conducted on a Waters instrument comprising a separation module (Waters 2695), an automatic injector, a photodiode array detector (Waters 2998), and a system controller (Empower login), with an Xbridge BEH130 C18 reversed-phase analytical column (4.6 mm × 100 mm, 3.5 μm).
Following transfer of the manually optimized method from the Thermo Scientific to Waters instrument, the minimum and maximum values and step sizes for nine LC and MS parameters were selected (Supplementary Table S5) and then optimized during an ∼48-h fully automated LC-MS/MS study.
Five musicians, each in his or her own tank filled with water, played instruments — a violin, gongs, a hand-cranked organ — that had been adapted, or created, to function without air.
The results show the effectiveness and potential utility of the proposed methodological framework for irrigation water pricing instruments' selection.
