A universal mass tag based on polystyrene nanoparticles for single-cell multiplexing with mass cytometry

Area of Science:

• Biotechnology
• Analytical Chemistry
• Materials Science

Background:

• Mass cytometry (MC) enables high-dimensional biomarker analysis in single cells.
• Current metal chelating polymer (MCP) mass tags limit MC sensitivity and multiplexing.
• There is a need for improved mass tag strategies in MC.

Purpose of the Study:

• To develop a novel mass tag strategy for MC using polystyrene nanoparticles (PS-NPs).
• To enhance MC sensitivity and reduce nonspecific binding (NSB).
• To introduce new MC detection channels.

Main Methods:

• Synthesized metal-doped PS-NPs as MC mass tags.
• Optimized cell staining buffer to minimize NSB of non-functionalized PS-NPs.
• Evaluated compatibility and sensitivity of PS-NP mass tags against MCP tags.

Main Results:

• Metal-loaded PS-NPs are detectable by MC without requiring extremely small particle sizes.
• An altered cell staining buffer effectively reduced NSB.
• PS-NP mass tags demonstrated 5-fold higher sensitivity and compatibility with MCP tags.
• Hafnium (Hf)-doped PS-NP mass tags enabled four new MC detection channels (177Hf, 178Hf, 179Hf, 180Hf).

Conclusions:

• This work presents a new strategy for designing MC mass tags using cost-effective PS-NPs.
• The developed method offers a viable approach to lower NSB in MC.
• This opens possibilities for new MC mass tag candidates and expanded detection capabilities.