Chemical functionalization of polysilicon microparticles for single-cell studies

Area of Science:

• Biotechnology
• Materials Science
• Cell Biology

Background:

• Studying individual cells requires reliable methods for cell identification and tracking.
• Polycrystalline silicon (polysilicon) microparticles offer a versatile platform for cell surface modification.

Purpose of the Study:

• To develop and compare methods for functionalizing polysilicon microparticles with ligands for selective cell attachment.
• To evaluate the efficiency and stability of ligand immobilization on microparticles.
• To demonstrate the utility of functionalized microparticles for single-cell monitoring.

Main Methods:

• Two functionalization approaches (adsorption and covalent attachment) were tested on cylindrical and shape-encoded polysilicon microparticles.
• Ligand immobilization efficiency and particle stability were assessed using fluorophore-labeled ligands.
• Vero cells were labeled with modified microparticles and tracked using fluorescence imaging and microscopy.

Main Results:

• Covalent attachment of ligands to polysilicon microparticles, via aldehyde-terminated silane modification, yielded superior immobilization and stability.
• Shape-encoded microparticles (bar codes) were successfully used to label and track individual cells for up to one week.
• Cell viability remained unaffected, and bar code identification was feasible with standard optical microscopy.

Conclusions:

• Covalent functionalization of polysilicon microparticles is an effective strategy for selective cell labeling and long-term tracking.
• Functionalized microparticles, particularly shape-encoded ones, show promise for advanced single-cell analysis and automated cell sorting.