Objective To develop for the determination of 16 kinds of rare earth elements in plant agricultural products by micro-open graphite digestion coupled with inductively coupled plasma mass spectrometry. Methods Using the micro-open graphite digestion as the pretreatment method, the effects of acid digestion system, digestion time and matrix elements (K+, Na+, Ca2+, Mg2+, Fe2+, Cu2+, Zn2+, Mn2+) on rare earth elements were investigated. Results The results showed that adding HF to the HNO3+HClO4 mixed acid system facilitated complete digestion of samples and significantly improved the recovery of rare earth elements. When the concentration ratio of matrix elements to rare earth elements reached 4 orders of magnitude, there was no significant interference in the determination of rare earth elements. Under optimal conditions, the standard curves exhibited good linear relationships (r≥0.999) in the range of 0-50 μg/L, with the limits of detection was 0.001-0.006 mg/kg. The method was validated using national standard reference materials, and the determination results of each rare earth element were generally consistent with the reference values. The recoveries of spiked samples were 83.2%-110.3% and the relative standard deviations were 1.0%-10.4%. Conclusion The method features simple operation, strong anti-interference capability, and high accuracy, making it suitable for rapid determination of rare earth elements in batch plant agricultural products.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |