Table 2. Instrumentation and operational settings.
| ICP-MS | |
|---|---|
| Instrument | Magnetic sector-based ICP-MS (AttoM, Nu Instruments, UK) |
| ICP forward power | 1300 W |
| Argon gas flow rate | |
| Coolant gas | 13.0 L min−1 |
| Auxiliary gas | 1.0 L min−1 |
| Monitored isotopes | 107Ag and 197Au |
| Dwell time | 50 μs |
| Detector | ETP full size multiplier |
| Detection system | Pulse counting mode with attenuator system |
| Desolvation sample introduction system | |
| Instrument | Aridus II (Teledyne Cetac Technologies, USA) |
| Sample uptake rate | 0.2 mL min−1 |
| Spray chamber temperature | 110°C |
| Membrane oven temperature | 160°C |
| Sweep gas | Ar (4.8 L min−1) |
| Laser ablation system | |
| Instrument | Nd:YAG laser (MOPA 266–200 mW, CryLas, Germany) |
| Wavelength | 266 nm (FHG) |
| Pulse width | 1 ns |
| Fluence | 0.2 to 3.0 J cm−2 |
| Repetition rate | 10 Hz |
| Carrier gas | He (0.60 L min−1) |
| Makeup gas | Ar (1.0 L min−1) mixed after the ablation cell using T-piece connector |
| Scanning speed | 100 μm s−1 |
| Laser beam size | 5 μm |