Table 1 Operating conditions of LC-ICP-MS.

Analytical column

Phenomenex Luna C₁₈, 5 μm, 250 mm × 4.6 mm

Mobile phase A

1.6 mM EDTA·2Na and 0.04 mM KH₂PO₄ with 60% (v/v) Methanol-H₂O (pH = 6.0)

Mobile phase B

Ultrapure water

Column temperature

Room temperature

Injection volume (µL)

100

Flow rate (mL/min)

1.0

Gradient Program

Time (min)

A (%)

B (%)

0.00

20

80

8.00

70

30

15.00

20

80

ICP-MS conditions

Nebulizer gas flow rate (L/min)

0.770

Auxiliary gas flow rate (L/min)

1.00

Plasma gas flow rate (L/min)

15

Oxygen flow rate (mL/min)

20.00

RF power (W)

1600

Acquisition mode

Peak hopping

Dwell time (ms)

10

Atomizing Chamber temperature (^oC)

0

Sample/skimmer Cone

Platinum cones

Central tube (mm)

1.0

Ion monitored

⁵⁹Co

Mode

He collision