Development of Desolvation System for Single-cell Analysis Using Droplet Injection Inductively Coupled Plasma Atomic Emission Spectroscopy

Abstract

With a view to enhance the sensitivity of analytical instruments used in the measurement of trace elements contained in a single cell, we have now equipped the previously reported micro-droplet injection system (M-DIS) with a desolvation system. This modified M-DIS was coupled to inductively coupled plasma atomic emission spectroscopy (ICP-AES) and evaluated for its ability to measure trace elements. A flow rate of 100 mL/min for the additional gas and a measurement point -7.5 mm above the load coil (ALC) have been determined to be the optimal parameters for recording the emission intensity of the Ca(II) spectral lines. To evaluate the influence of the desolvation system, we recorded the emission intensities of the Ca(I), Ca(II), and H-β spectral lines with and without inclusion of the desolvation system. The emission intensity of the H-β spectral line reduces and the magnitude of the Ca(II)/Ca(I) emission intensity ratio increases four-fold with inclusion of the desolvation system. Finally, the elements Ca, Mg, and Fe present in a single cell of Pseudococcomyxa simplex are simultaneously determined by coupling the M-DIS equipped with the desolvation system to ICP-AES.

New Frontiers of Metallomics: Elemental and Species-Specific Analysis and Imaging of Single Cells

“…In addition, they performed open vessel digestion of washed yeast cells for multielement analysis, determining absolute amounts per single cell for Na (0.91 fg), Mg (9.4 fg), Fe (5.9 fg), Cu (0.54 fg), Zn (1.2 fg), and Se (72 fg). Ishihara et al (2015) developed a desolvation system for micro-droplet injection system (M-DIS) in order to detect trace metals in the unicellular alga Pseudococcomyxa simplex by ICP-AES. In the M-DIS system, the cell solution is not nebulized but introduced at the center of the ICP as a single micro-droplet with a diameter between 30 and 70 μm.…”

Development of a Dual Plasma Desorption/Ionization System for the Noncontact and Highly Sensitive Analysis of Surface Adhesive Compounds

“…The wiping method 2 – 6 ) or direct analysis in real time (DART) developed by Cody et al 7 ) are good examples of such methods. In the wiping method, after the surface compounds are wiped with a cotton swab or gauze, various analyses, such as organic or inorganic analyses, 8 – 10 ) are performed according to the type of the target compounds. Because the collected sample can be examined using various analytical methods, 11 ) it is thought that an increase in the number of degrees of freedom in the analysis can allow us to obtain highly reliable results.…”

Local cooling, plasma reheating and thermal pinching induced by single aerosol droplets injected into an inductively coupled plasma

“…Recent advances in single-particle inductively coupled plasma (sp-ICP) [1] spectrometry enable the elemental and isotopic measurements of individual entities (e.g., nanoparticles [2,3] and biological cells [4,5]), and provide information such as particle-size distributions [2] and their stoichiometry [3] that are otherwise unavailable from simple bulk chemical analyses. One approach for sp-ICP measurement is to embed the particle inside a solution droplet and introduce this droplet into the ICP.…”

“…The current growing interest in nanoparticle analysis with sp-ICP spectrometry creates a new demand for a better fundamental understanding of the ICP. Recent studies devoted to understanding these fundamental characteristics and behavior of the plasma when a relatively large amount of mass is introduced by a single droplet include: the local effect 5 on plasma excitation conditions by an atomizing analyte droplet [21], matrix effects from injection of a single analyte droplet and particle [22], change of plasma impedance during single droplet introduction [23], and shift of radiofrequency from a free-running generator upon injection of a single droplet into the plasma [24].…”