Agilent 7500 series icp ms

The analysis method of groundwater Cd samples was strictly in accordance with the GB/T 5750.6-2006 standard [40 ]. A certain amount of the water sample was taken for direct determination by using inductively coupled plasma mass spectrometry (Agilent 7500 Series ICP-MS, Agilent Technologies Company, Santa Clara, CA, USA). When the water sample was turbid, a 0.45-um membrane was used for filtration. The accuracy of the analytical method was tested by a standard addition recovery test (the standard addition amount was ten times the detection limit of the analytical method). The standard addition recovery rate was 90–110%. The precision of the analytical method was assessed by the repeated analysis of multiple samples. When the content of the tested components in the sample was higher (or equal) than ten times the detection limit, the relative standard deviation of the 12 tests was less than 15%.

THP-1 cells were stimulated by NiCl₂ for 24 h in Fig. 1a and b, or for the indicated time in Fig. 1c and d. The cells were stimulated by NiCl₂ and/or other metal chlorides for 24 h in Figs 2, 4 and 5. After the incubation, they were collected and washed five times with PBS (phosphate-buffered saline), and then suspended in 150 μl PBS. The cell suspension was sonicated for 30 s and the aliquot was diluted 10-fold with 5% (w/w) HNO₃. The concentration of Ni²⁺ and other metal ions in each sample was determined by Agilent 7500 Series ICP-MS (Agilent Technology, Santa Clara, CA).
To determine the metal concentrations in the mouse skin and serum, circular skin tissue sections (1 cm in diameter) from the region surrounding the Ni wire were excised and the wet weight of skin was measured. The skin tissue sample, approximately 80 mg, was boiled in 3 ml 69% (w/w) HNO₃ for 30 min, and then, 300 μl 30% (w/v) H₂O₂ was added to the samples, on ice. The skin samples were then boiled again for approximately 30 min, and pure water was added to attain a total weight of 10 g. Mouse blood was incubated for 12 h at 4 °C and then centrifuged at 1,200 × g, 4 °C for 30 min. The supernatant was diluted 10-fold with 5% (w/w) HNO₃, and centrifuged at 500 × g, 4 °C for 5 min. The supernatant was collected. The Ni²⁺, Zn²⁺ concentration of each sample was also determined by ICP-MS.

The content of mineral elements was measured by ICP-MS (Agilent 7500 Series ICP-MS, Agilent Technologies, Santa Clara, CA, USA). The method of ICP-MS analysis for samples was carried out according to Mi’s method (Mi, Shang, Li et al., 2019). The analysis of each sample was performed in triplicate and quantified using external standards. The Environmental Calibration Standard (Part Number 5183-4688) and the Multi-Element Calibration Standard (Part Number 8500-6944), supplied by Agilent Technologies (Palo Alto, CA, USA), were used as the standard solution and the determination coefficient of the standard curve was higher than 0.99. Internal Standard Multi-Element Mix #4 (Part Number 5190-8593), containing ⁷²Ge, ¹¹⁵In, and ²⁰⁹Bi and supplied by Agilent Technologies (Palo Alto, CA, USA), was used to ensure the stability of the instrument. Samples were remeasured whenever the relative standard deviation (RSD) of internal standards was higher than 10%.