Poroshell ec c18 column

Total
bacterial lipids were extracted into chloroform and methanol
for analysis by HPLC-MS. The lipid samples were prepared at 1 mg mL^–1 in the starting mobile phase (50% A and 50% B), and
10 μL was injected into a reversed-phase HPLC system (Agilent
1260 series) using an Agilent Poroshell EC-C18 column (1.9 μm,
3 × 50 mm) coupled with an Agilent guard column (2.7 μm,
3 × 5 mm) and analyzed by an Agilent 6546 Accurate-Mass Q-TOF
mass spectrometer. The mobile phases were A [2 mM ammonium formate
in 90/10 methanol/water (v/v) and B (3 mM ammonium formate in 85/15/0.1
1-propanol/cyclohexane/water (v/v/v)]. The gradients were: 0–2
min, 50% A; 2–10 min, from 50% A to 100% B; 10–15 min,
100% B; 15–17 min, from 100% B to 50% A; and 17–20 min,
50% A. CID-MS was carried-out with a collision energy of 35 V, and
the isolation width was set to 1.3 m/z.

The mandarin peel and kudzu flower are listed as Old Dietary Ingredients marketed in the US before 15 October 1994 [19 ]. Therefore, they might be used legally in a dietary supplement without submitting the Food and Drug Administration notification. The test and placebo products were provided by the LG Household & Health Care (Seoul, Korea). In brief, the 70% ethanolic extract of kudzu flower and aqueous extract of mandarin peel were spray-dried separately and mixed at the ratio of 6.5:5. The KM, lactose, crystalline cellulose, sodium carboxymethyl starch, silicon dioxide, magnesium stearate, and cacao color were packed in a capsule to provide a dose of 383.4 mg KM. For the placebo capsule, KM was replaced with an equal weight of lactose. The test product was standardized to contain 70.3 mg/g of three tectorigenin derivatives from the kudzu flower and 51.7 mg/g hesperidin from mandarin peel using a high-performance liquid chromatograph equipped with a variable wavelength detector (Agilent Technologies, Santa Clara, CA, USA) and Poroshell EC-C18 column (2.1 mm × 1000 mm, 2.7 μm).

The EtOAcPart was also analysed by LC–ESI/TOF-MS with a 1200 Series LC-chromatograph (Agilent, Palo Alto, CA, USA) coupled with a MicrOTOF II time-of-flight mass spectrometer (Bruker Daltonics, Inc., Billerica, MA, USA). 5 µL injection was performed with an autosampler on a Poroshell EC-C18 column (100 × 2.1 mm; 2.7 µm, Agilent, Palo Alto, CA, USA). The source temperature was set at 200 °C, the drying gas (nitrogen) flow rate was 10.0 L/min and the nebulizer gas (nitrogen) pressure was 4 bar. Data were acquired in negative mode in the range of m/z 100–1500. The capillary voltage was 3.8 kV, the capillary exit voltage was −150 V, the skimmer 1 and 2 voltages were 50 V and 23 V, respectively, the hexapole 1 voltage was set to −23 V, the hexapole RF voltage was 120 Vpp, lens 1 transfer was 68 μs and lens 1 pre plus stage was 7 μs. Mass calibration was achieved by infusing ammonium formate in an isopropanol–water mixture (1:1, v/v) as an external standard. All data were analysed using Bruker Daltonics ESI Compass Data Analysis Version 4.0 SP 1 (Bruker Daltonics Inc., Billerica, MA, USA). The mobile phase consisted of spectroscopic grade methanol (B) and ultrapure water (A) containing 0.05% (v/v) formic acid. The linear gradient elution was set from 10% to 100% of B in 90 min at a flow rate of 0.3 mL/min.

Cannabinoid content was determined by LC-MS/MS, as previously described [65 (link)]. Analyses were performed on Agilent 1200 HPLC in tandem with mass spectrometry Agilent 6460 JetStream triple quad detector. Agilent Poroshell EC-C18 column with a particle size of 2.7 µm and dimensions of 100 × 2.1 mm ID was used. The mobile phase consisted of ultra-pure water with the addition of 0.1% formic acid (A) and acetonitrile with 0.1% formic acid (B) using the gradient method with a flow of 0.3 mL/min. The gradient method was composed of multiple linear gradients as follows: 0 min, 34% B; 8 min, 34% B; 12 min, 95% B; 13 min, 95% B; 14 min, 95% B; 20 min, 34% B; and 3 min post time. Detailed parameters for LC-MS/MS method are shown in Table 6.
The column temperature was stable at 35 °C. Negative ionisation was used on the mass spectrometer, the temperature of the carrier gas was 300 °C, and that of the supporting gas was 250 °C. The total gas flow was 16 L/min.
The calibration curve for each cannabinoid was plotted in the concentration range of 2.5–200.0 ng/mL with good linearity in the measurement range between calibration points, R2 > 0.999. All points were measured in triplicates with an RSD < 3%.

Male SD rats were intragastrically treated with normal saline (control) or HQR (9.0 g/kg/d) once daily for 7 days. Two hours after the last administration, blood was collected from the aorta ventralis, stored at 4°C for 1 h and centrifuged at 2000 rpm/min for 30 min. Serum samples from the same group were pooled, inactivated in a 56°C water bath for 30 min and sterilized by filtration. The HQR‐containing serum was stored at −80°C for subsequent vitro experiments.
The Agilent 1290UHPLC Liquid Chromatography System and Agilent MassHunter Workstation Data Acquisition Software (version B.06.00) were used for component analysis of HQR ‐containing serum. The chromatography conditions were as follows: Agilent Poroshell EC‐C18 column (internal diameter, 100 × 2.1 mm, 1.9 μm), sample size of 5 μl, temperature of 20°C, velocity flow of 0.3 ml/min, mobile phase A containing 0.1% formic acid in methanol, mobile phase B containing 0.1% formic acid in an aqueous buffer, 0–1 min mobile phase A 5%, 1–10 min mobile phase A 5–80%, 10–13 min mobile phase A 80% and stop time of 13 min. The mass spectrometry conditions were as follows: multiple reaction monitoring (MRM) and negative ion scanning mode. The internal standard was mangostin and epinastine, with an accurate weight of 1 mg standard and 5 ml of methanol diluted 500 times. Plasma samples were prepared by the methanol precipitation method.

The analysis was performed on an Agilent-1200 series HPLC system coupled to an Agilent G6130A single quadrupole MS instrument (Agilent Technologies, Santa Clara, CA, USA). The separation of the extracted compounds was carried out on an Agilent Poroshell EC-C18 column (2.1 mm × 100.0 mm, 1.9 µm) at 40 °C. The mobile phase was methanol (solvent A) and 0.1% formic acid aqueous solution (solvent B), respectively. Gradient elution was performed at 0.3 mL/min with a total run time of 15.0 min: 20% B held for 1 min, 1–4 min, 20%B→5%B and held for 4 min; 8–8.1 min, 5%B→20%B; and finally held for 6.9 min.
The electrospray ionization (ESI) was set at positive ion mode. Source conditions were set as follows: drying gas (N₂) flow 10 L/min; drying gas temperature 350 °C; capillary voltage 3.0 kV. The instrument was operated in the scan mode in the range from 50–750 (m/z) for qualitative analysis and selected ion monitoring (SIM) mode for quantitative analysis with the parameters described in Table 1.
High-efficiency hair grinder (JXFSTPRP-CL; Jingxin, Shanghai, China) was used for hair samples preparation.