McLean J A, Zhang H, Montaser A
Department of Chemistry, George Washington University, Washington, D.C. 20052, USA.
Anal Chem. 1998 Mar 1;70(5):1012-20. doi: 10.1021/ac9708553.
A simple, relatively low-cost direct injection high-efficiency nebulizer (DIHEN) is introduced for argon inductively coupled plasma (Ar ICP) spectrometry. The DIHEN may be operated at solution uptake rates of 1-100 microL/min. Analytical performance indexes for the DIHEN and fundamental characteristics of the aerosol produced are obtained using an ICP mass spectrometer (ICPMS) and a two-dimensional phase Doppler particle analyzer (2D PDPA), respectively. Results are compared to those obtained with a conventional crossflow pneumatic nebulizer (PN), equipped with a Scott-type spray chamber. Droplet sizes and velocities produced with the DIHEN are smaller than those reported for the direct injection nebulizer (DIN). The DIHEN offers optimal sensitivity at low injector gas flow rates (approximately 0.25 L/min) and high rf power (approximately 1.5 kW). For the 17 elements tested, detection limits (ppt) and sensitivities achieved with the DIHEN (at 85 microL/min) are similar to, or better than, those obtained on the same instrument using the PN (at 1 mL/min). However, because the primary aerosol is injected directly into the plasma, oxide-to-metal ion ratios (MO+/M+) are high, as in the case of the DIN. The utility of the DIHEN for the analysis of small-volume samples is demonstrated by microscale flow injection analysis (muFIA) of Cr bound to human lung DNA. Detection of Cr at the femtogram level is feasible.
本文介绍了一种用于氩电感耦合等离子体（Ar ICP）光谱分析的简单、成本相对较低的直接进样高效雾化器（DIHEN）。DIHEN可在1 - 100微升/分钟的溶液进样速率下运行。分别使用电感耦合等离子体质谱仪（ICPMS）和气溶胶二维相位多普勒粒子分析仪（2D PDPA）获得了DIHEN的分析性能指标以及所产生气溶胶的基本特性。将结果与配备斯科特型喷雾室的传统交叉流气动雾化器（PN）所获得的结果进行了比较。DIHEN产生的液滴尺寸和速度比直接进样雾化器（DIN）所报道的要小。DIHEN在低进样器气体流速（约0.25升/分钟）和高射频功率（约1.5千瓦）下具有最佳灵敏度。对于所测试的17种元素，DIHEN（在85微升/分钟时）实现的检测限（ppt）和灵敏度与使用PN（在1毫升/分钟时）在同一仪器上获得的结果相似或更好。然而，由于初级气溶胶直接注入等离子体中，与DIN情况一样，氧化物与金属离子的比率（MO⁺/M⁺）较高。通过对与人类肺DNA结合的铬进行微尺度流动注射分析（μFIA），证明了DIHEN在分析小体积样品方面的实用性。在飞克水平检测铬是可行的。
