Flow cytometry for intracellular SPION quantification: specificity and sensitivity in comparison with spectroscopic...

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Toxicology

Background:

• Super-paramagnetic iron oxide nanoparticles (SPIONs) have promising biomedical applications due to their unique properties.
• Comprehensive safety assessments, including accurate intracellular SPION quantification, are essential for clinical translation.
• Understanding concentration-dependent toxicity is critical for safe SPION development.

Purpose of the Study:

• To compare the accuracy and reliability of different methods for quantifying intracellular SPIONs.
• To evaluate the potential of flow cytometry as a method for determining cellular SPION content.
• To investigate the relationship between SPION type, cellular uptake, and toxicity.

Main Methods:

• Comparison of ultraviolet spectrophotometry, magnetic particle spectroscopy, and atomic adsorption spectroscopy for SPION quantification.
• Correlation of flow cytometry side scatter data with actual intracellular SPION amounts.
• Assessment of SPION internalization and toxicity in human umbilical vein endothelial cells.

Main Results:

• Flow cytometry provides a rapid and reliable assessment of cellular SPION content, correlating well with atomic adsorption spectroscopy.
• SPION internalization and toxicity are dependent on SPION type and concentration.
• Lauric acid-coated SPIONs (SEON(LA)) showed higher toxicity and side scatter intensity compared to SEON(LA-BSA) and Rienso® particles.

Conclusions:

• Flow cytometry is a valuable tool for estimating SPION uptake in mammalian cells.
• This method can accelerate the safety evaluation of nanoparticle products for biomedical use.
• SPION type significantly influences cellular uptake, toxicity, and potential side scatter signals.