Integration of capillary vibrating sharp-edge spray ionization as a nebulization device for ICP-MS

Abstract

This work presents the first use of capillary vibrating sharp-edge spray ionization (cVSSI) as a nebulization technique for inductively coupled plasma mass spectrometry (ICP-MS). When used for ICP-MS sample introduction, cVSSI acts as a low-flow, in-line, continuous nebulization source. cVSSI differs from conventional pneumatic nebulizers in that the nebulization process is independent from the carrier gas used to transport nebulized aerosols into the plasma. To integrate cVSSI with ICP-MS, we constructed a sample introduction chamber using fused deposition modeling; the design, manufacturing, and operation of this chamber will be discussed. We demonstrate the utility of cVSSI as a nebulization device for ICP-MS analysis through characterization of device performance in terms of produced droplet size distribution, sample introduction efficiency, analytical sensitivity, detection limits, linear working range, and long-term stability. With our cVSSI sample introduction system, sensitivity for Ce was 1.98 × 10⁴ counts s^–1 ng^–1 mL^–1 at a sample flow rate of 15 μL min⁻¹ with an absolute sensitivity of 5.24 × 10¹⁷ counts g⁻¹. Signal stability is observed to have a relative standard deviation of less than 10% across a 45 minutes measurement.