Analysis of Neat Biofluids Obtained During Cardiac Surgery Using Nanoparticle Tracking Analysis: Methodological...

Area of Science:

• Biotechnology
• Nanomedicine
• Biomarker Discovery

Background:

• Small extracellular vesicles (sEVs) are key in cell signaling and disease diagnostics.
• Nanoparticle tracking analysis (NTA) is a common method for sEV quantification in biofluids.
• NTA accuracy can be compromised by sample handling, machine settings, and lipoprotein interference.

Purpose of the Study:

• To provide methodological insights into NTA measurements for sEVs.
• To investigate factors affecting the reliability and repeatability of NTA in biofluid analysis.
• To identify critical parameters for accurate sEV quantification in clinical applications.

Main Methods:

• Systematic investigation of NTA parameters using human serum and pericardial fluid.
• Analysis of variables including lipoprotein contamination, freeze-thaw cycles, filtration, diluents, video length, and particle count.
• Comparison of critical versus less critical NTA settings.

Main Results:

• Lipoprotein contamination, freeze-thaw cycles, filtration, diluents, and video length significantly impact NTA results.
• Focus and "Maximum Jump" settings are less critical if appropriate, but multiple videos are recommended.
• Consistent protocols are essential for reproducible sEV quantification.

Conclusions:

• NTA is a valuable, though perfectible, tool for sEV analysis.
• Robust and consistent sample handling protocols are vital for reliable sEV quantification.
• Standardized NTA methods can facilitate the development of clinical biomarkers for cardiovascular disease.