Agilent has further improved the sample throughput capabilities of its 7500cx ICP-MS with Octopole Reaction System (ORS) using a newly configured Integrated Sample Introduction System–Discrete Sampling (ISIS-DS) accessory, and helium collision mode. Employing this new methodology, a complete suite of 30 or more elements can be analyzed in compliance with USEPA criteria (spectrum mode, three replicates, and sub-ppb MDLs) in approximately 75 seconds, sample to sample, with excellent removal of polyatomic interferences. Performance data showing stability, interference control, accuracy, precision, and washout are presented.
Agilent has improved the sample throughput of its 7500cx ICP-MS by configuring the Integrated Sample Introduction System—Discrete Sampling (ISIS-DS) accessory with helium collision mode. This setup allows for the analysis of a complete suite of 30 or more elements in compliance with USEPA criteria in approximately 75 seconds per sample. The method utilizes a single collision cell mode, eliminating the need for gas switching and significantly reducing analysis time compared to multi-mode operation.
The document details the ISIS-DS configuration, which includes a modified discrete sampling setup with a six-port valve and sample loop. Key features include a large peristaltic pump downstream of the valve to prevent contamination, a tee joint for online internal standard addition, and optimized tubing to minimize delay. The system achieves a total run time of about 75 seconds per sample with a low sample consumption of approximately 2.2 mL per sample.
| Total acquisition time (3 replicates) | 29 seconds |
|---|---|
| Loop volume | 300 pL |
| Loop rinse and fill time | 10 seconds |
| Acquisition delay | 15 seconds |
| Steady state signal time | 30 seconds |
| Total run time | approximately 75 seconds |
| Sample consumption | 2.2 mL per sample |
| Number of elements | 31 |
A complete suite of 30 or more elements can be analyzed in approximately 75 seconds, sample to sample.
The sample consumption is approximately 2.2 mL per sample per analysis.