Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong Special Administrative Region.
Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong Special Administrative Region; HKBU Institute of Research and Continuing Education, Shenzhen Virtual University Park, Shenzhen, China.
Anal Chim Acta. 2022 Sep 15;1226:340258. doi: 10.1016/j.aca.2022.340258. Epub 2022 Aug 16.
Single particle-inductively coupled plasma-mass spectrometry (SP-ICP-MS) was used in the analysis of single particles/cells. Although quadrupole mass analyzers are widely used, the long settling time restricts measurement to single elements in individual particles. Recently, dual-elemental analysis has successfully been developed with the assistance of oxygen gas in the collision cell. This simple approach greatly expands the capability of quadrupole-based ICP-MS. In this study, we adopted bandpass mode in the first quadrupole (Q1) to improve the limit of detection of single particles against spectral interference. A model was developed to explain the rationale behind the selection of quadrupole voltages. The quadrupole voltages were optimized systematically so that the mass bandwidth of Q1 allowed the transmission of two target analytes while the interference species were rejected. As a result, the signal from the polyatomic interference was reduced by 98% with no significant change in the analyte signal. The bandpass mode was further applied to accurately determine the isotope ratio of Ag/Ag in 80-nm Ag nanoparticles, as well as the Ag content in AgSn alloy particles, under the polyatomic interference of ZrO originating from dissolved ions and particles. This technique was further applied to the determination of two Yb isotopes in algal cells with interference from Gd. Results indicate that this approach has great potential for assessing single particles and biological cells in the presence of severe interference from imaging agents, drugs, or biological fluids.
采用单颗粒进样电感耦合等离子体质谱法（SP-ICP-MS）分析单个颗粒/细胞。虽然四极杆质量分析器被广泛应用，但由于较长的沉降时间，其测量仅限于单个颗粒中的单个元素。最近，在碰撞池中添加氧气的辅助下，成功开发了双元素分析方法。这种简单的方法极大地扩展了基于四极杆的 ICP-MS 的能力。在本研究中，我们在第一四极杆（Q1）中采用带通模式来提高对单个颗粒中光谱干扰的检测限。建立了一个模型来解释选择四极杆电压的原理。系统地优化了四极杆电压，使得 Q1 的质量带宽允许传输两个目标分析物，同时拒绝干扰物质。结果，多原子干扰的信号降低了 98%，而分析物信号没有明显变化。带通模式进一步用于在溶解离子和颗粒产生的 ZrO 多原子干扰下，准确测定 80nm Ag 纳米颗粒中 Ag/Ag 的同位素比以及 AgSn 合金颗粒中的 Ag 含量。该技术进一步应用于藻类细胞中两个 Yb 同位素的测定，同时存在来自造影剂、药物或生物体液的 Gd 干扰。结果表明，该方法在存在成像剂、药物或生物体液严重干扰的情况下，对单个颗粒和生物细胞的评估具有很大的潜力。
