Background

The measurement of selenium in human plasma is useful to assess deficiency or toxicity. The presence of gadolinium in clinical samples following administration of certain contrast agents used for magnetic resonance imaging can cause a significant positive bias in selenium results when measured using quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS).

Methods

A mathematical equation to correct for gadolinium interference was assessed using both patient samples and commercial quality control/external quality assurance (QC/EQA) materials spiked with gadolinium. Samples were analysed using an Agilent 7900 ICP-MS operated in ‘narrow peak’ (half-mass) mode. Accuracy was evaluated by comparing corrected selenium results with target concentrations.

Results

Corrected results were found to be accurate at all gadolinium concentrations tested (2, 4, 10 and 20 mg/L). Average recoveries ranged from 97.4 to 106.5%. Results for QC/EQA materials were within specified target ranges. Within-run imprecision was <3%, and between-run imprecision was <4.3%, demonstrating robustness.

Conclusions

The correction equation described here is a simple method to correct for gadolinium interference on plasma selenium measurement using ICP-MS. This approach eliminates the need for specimen recollections, and improves patient care by reducing laboratory turnaround times and preventing delays in diagnosis/treatment.

中文翻译：

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一个简单的方程式，用于校正电感耦合等离子体质谱法测定plasma对硒硒的干扰。

背景

人血浆中硒的测量可用于评估缺乏或毒性。当使用四极感应耦合等离子体质谱法（Q-ICP-MS）进行测量时，在临床样品中施用某些用于磁共振成像的造影剂后，lin的存在会导致硒结果产生显着的正偏差。

方法

使用患者样品和掺有commercial的商业质量控制/外部质量保证（QC / EQA）材料评估了校正g干扰的数学方程式。使用在“窄峰”（半质量）模式下运行的Agilent 7900 ICP-MS分析样品。通过将校正的硒结果与目标浓度进行比较来评估准确性。

结果

发现校正后的结果在所有测试的concentrations浓度（2、4、10和20 mg / L）下都是准确的。平均回收率在97.4至106.5％之间。QC / EQA材料的结果在指定的目标范围内。批内不准确性<3％，批间不准确性<4.3％，证明了其鲁棒性。

结论

此处描述的校正方程式是一种使用ICP-MS校正g对血浆硒测量中干扰的简单方法。这种方法消除了标本采集的需要，并通过减少实验室周转时间并防止诊断/治疗的延迟来改善对患者的护理。