Off-Line Coupling of Capillary Electrophoresis to Substrate-Assisted Laser Desorption Inductively Coupled Plasma Mass Spectrometry
| Authors | |
|---|---|
| Year of publication | 2008 |
| Type | Article in Periodical |
| Magazine / Source | Analytical Chemistry |
| MU Faculty or unit | |
| Citation | |
| Web | http://pubs.acs.org/journals/ancham/index.html |
| Field | Analytic chemistry |
| Keywords | capillary electrophoresis; laser ablation; laser desorption; inductively coupled plasma; elemental speciation; off-line coupling; SALD |
| Description | A novel off-line coupling of capillary electrophoresis (CE) and inductively coupled plasma mass spectrometry (ICPMS) is reported here. The coupling interface is based on the connection of a separation capillary to a deposition capillary via a liquid junction maintaining high separation efficiency and sample utilization due to the self-focusing effect and lack of pressure-induced flow in comparison with nebulizer-like interfaces. The separation is recorded in the form of droplets of CE effluent on a suitable substrate s a poly(ethylene terephthalate) glycol (PETG) sample plate placed inside a partially evacuated chamber. Substrate-assisted laser desorption (SALD) is used to vaporize the sample fractions and to enable further transfer to the ICPMS. The mechanism of SALD is examined using model samples deposited on a variety of substrates. The highest response is obtained for a PETG substrate; sample desorption due to ablation of PETG is found to outweigh direct ablation of sample. Detection limits are given for several metal elements. Finally, a rapid (2.5-min), high-resolution separation of CrIII/CrVI species injected in subpicomolar quantity is shown. |
| Related projects: |
|