Quantification and size-profiling of extracellular vesicles using tunable resistive pulse sensing.

Area of Science:

• Biotechnology
• Nanotechnology
• Biomedical Engineering

Background:

• Extracellular vesicles (EVs), including microvesicles and exosomes, are prevalent in bodily fluids.
• EVs are implicated in physiological and pathological processes like coagulation, immune responses, and cancer.
• EVs show promise as therapeutic agents for drug delivery and regenerative medicine.

Purpose of the Study:

• To describe a protocol for quantifying and profiling the size of extracellular vesicles (EVs).
• To present tunable resistive pulse sensing (tRPS) technology as a method for EV characterization.
• To offer a real-time calibration technique for overcoming challenges in measuring EVs in biological fluids.

Main Methods:

• Utilized tunable resistive pulse sensing (tRPS) technology with the qNano system.
• Detected EVs by monitoring their passage through a nano-sized pore.
• Employed a real-time calibration approach using spiked polystyrene beads for enhanced accuracy.

Main Results:

• The tRPS method allows for relatively fast determination of EV concentration and size.
• The protocol requires small sample volumes and does not necessitate EV purification or concentration.
• The real-time calibration technique addresses challenges in direct EV measurement within biological fluids.

Conclusions:

• Tunable resistive pulse sensing (tRPS) provides an effective method for characterizing extracellular vesicles (EVs).
• This protocol facilitates accurate EV quantification and size profiling, crucial for their study and application.
• The described technique enhances the reliability of EV measurements in complex biological samples.