Single-cell analysis by ICP-MS/MS as a fast tool for cellular bioavailability studies of arsenite

Area of Science:

• Analytical Chemistry
• Cell Biology
• Toxicology

Background:

• Single-cell inductively coupled plasma mass spectrometry (SC-ICP-MS) enables elemental analysis at the single-cell level.
• Traditional methods often require cell fixation, which can alter cell membranes and affect results.
• Assessing cellular bioavailability of toxic elements like arsenite requires precise and reliable single-cell measurement techniques.

Purpose of the Study:

• To introduce and validate a novel SC-ICP-MS/MS method for assessing cellular arsenite bioavailability.
• To demonstrate the direct measurement of arsenite in cells without fixation.
• To establish the reliability and feasibility of this new approach.

Main Methods:

• Utilized single-cell inductively coupled plasma mass spectrometry/mass spectrometry (SC-ICP-MS/MS) for direct cellular analysis.
• Incubated cells with arsenite (25 and 50 μM) for 0-48 hours.
• Validated results by comparing with conventional bulk ICP-MS/MS analysis and measuring sulfur and phosphorus.

Main Results:

• Successfully assessed cellular arsenite bioavailability for the first time using SC-ICP-MS/MS directly after re-suspending cells in water.
• Achieved a limit of detection of 0.35 fg per cell, demonstrating high sensitivity.
• Confirmed the avoidance of cell membrane permeabilization issues associated with fixation methods.

Conclusions:

• The developed SC-ICP-MS/MS method provides a direct, reliable, and sensitive approach for evaluating cellular elemental bioavailability.
• This technique overcomes limitations of traditional fixation methods, enabling more accurate single-cell elemental analysis.
• The study validates SC-ICP-MS/MS as a powerful tool for toxicological studies at the single-cell level.