Maxis 2 type qq tof ms instrument

A Maxis II type Qq-TOF MS instrument (Bruker Daltoniks, Bremen, Germany) equipped with an Apollo II electrospray ion source was used. The spray voltage was 4.5 kV. The resolution of the instrument was 40,000 at m/z 400 (FWHM), and the mass accuracy was <2 ppm (external calibration). N₂ was utilized as the drying gas (200 °C, 4.0 L/min), nebulizer gas (0.5 bar) and collision gas. The collision voltage was varied in the range of 20–90 V. The mass spectra were recorded by means of a digitizer at a sampling rate of 2 GHz. The spectra were calibrated externally by ESI tune mix, from Bruker. The spectra were evaluated with the Compass Data Analysis 4.4 software from Bruker (Bremen, Germany). The sample solutions were introduced directly into the ESI source with a syringe pump (Cole-Parmer Ins. Co., Vernon Hills, IL, USA) at a flow rate of 3 μL/min. The concentration of the samples was 0.01 mg/mL.

The high resolution mass spectrometric measurements were performed using a Maxis II type Qq-TOF MS instrument (Bruker Daltonics, Bremen, Germany) equipped with an electrospray ion-source where the spray voltage was 3.5 kV. N₂ was applied as drying (200 °C, 4.0 L/min) and nebulizer gas (0.5 bar). The mass spectra were recorded by means of a digitizer at a sampling rate of 2 GHz. The mass accuracy of the instrument is <600 ppb (internal calibration), the resolution is 40,000 at m/z 400 (FWHM). Each spectrum was calibrated internally with the sodium formate clusters. The spectra were evaluated with the Compass DataAnalysis 4.4 software (Bruker Daltonics, Bremen, Germany). The sample solutions were injected by a 7100 model capillary electrophoresis instrument without any separation. A fused silica capillary (70 cm × 7.5 µm (id)) was applied, with 130 s, 3 bar preconditioning, 40 s, 2 bar injection and 100 s, 3 bar as postconditioning. The samples were dissolved in ethanol: water 1:1 (v/v) with 0.02% formic acid at a concentration of 60 µg/mL on a dry basis. The concentrations of the deuterated internal standards were 0.146 and 0.210 µg/mL quercetin and rutin, respectively.

A Maxis II type Qq-TOF MS instrument (Bruker Daltonik, Bremen, Germany) equipped with an Apollo II electrospray ion-source was used in positive ion mode. The spray voltage was 4.0 kV. The resolution of the instrument was 40 000 at m/z 400 (FWHM), and the mass accuracy was better than 1 ppm (external calibration). N₂ was utilized as drying gas (200 °C, 4.0 L/min), nebulizer gas (0.5 bar) and collision gas. The collision energy was varied in the range of 50–130 eV in the laboratory frame. All precursor ions were selected with an isolation width of m/z 2.00. The mass spectra were recorded with a digitizer at a sampling rate of 2 GHz. The spectra were calibrated externally by ESI tune mix provided by Bruker Daltonik (Bremen, Germany). The spectra were evaluated with Compass Data Analysis 4.4 software (Bruker, Bremen, Germany). The sample solutions were introduced directly into the ESI source with a syringe pump (Cole-Parmer Ins. Co., Vernon Hills, IL, USA) at a flow rate of 3 μL/min.