Table 2.
Effect of NH4OH volume on the recoveries of As and Cd as well as the removal of interfering matrix elements from MVM stock solution with HF + NH4OH coprecipitation. Values are mean ± standard deviation of five separate preparations (n = 5)
| Analyte (recovery) |
NH4OH volume (µL) |
||
|---|---|---|---|
| 50 | 100 | 150 | |
| As (%) | 97 ± 3 | 99 ± 2 | 86 ± 2 |
| Cd (%) | 98 ± 7 | 95 ± 4 | 62 ± 4 |
| Matrix element (concentration) |
|||
| Mo (µg mL−1) | 0.68 ± 0.06 | 0.43 ± 0.04 | 0.35 ± 0.04 |
| Sn (µg mL−1) | 0.2 ± 0.04 | 0.05 ± 0.08 | 0.02 ± 0.02 |
| Mg (µg mL−1) | 1283 ± 33 | 10 ± 2 | 4 ± 0.6 |
| P (µg mL−1) | 1263 ± 136 | 812 ± 46 | 783 ± 34 |
| Ca (µg mL−1) | 418 ± 41 | 1 ± 0.5 | 0.5 ± 0.2 |
| K (µg mL−1) | 35 ± 3 | 34 ± 2 | 36 ± 3 |
| Na (µg mL−1) | 4 ± 0.5 | 3 ± 0.7 | 4 ± 0.4 |