Resistive-Pulse Analysis of Single Phospholipid Vesicles Using Quartz Nanochannels

Area of Science:

• Nanotechnology
• Biophysics
• Analytical Chemistry

Background:

• Vesicle and nanoparticle characterization is crucial for various scientific fields.
• Existing methods like DLS and SEM have limitations in speed or sample manipulation.
• Developing rapid, high-resolution sizing techniques is an ongoing research objective.

Purpose of the Study:

• To demonstrate the efficacy of the resistive-pulse method with quartz nanochannels for single vesicle and nanoparticle detection.
• To establish a correlation between nanochannel measurements and conventional sizing techniques.
• To highlight the potential of this electronic method for future vesicle analysis.

Main Methods:

• Utilizing cylindrical quartz nanochannels for resistive-pulse measurements.
• Detecting single phospholipid vesicles (100-300 nm) and polystyrene nanoparticles (170-400 nm).
• Analyzing translocations as individual square current pulses for size determination.

Main Results:

• Successfully detected and sized individual vesicles and nanoparticles using the nanochannel system.
• Observed excellent agreement between nanochannel-derived sizes and those obtained via dynamic light scattering (DLS) and scanning electron microscopy (SEM).
• Demonstrated the method's speed, simplicity, and reliance on cost-effective, in-house fabricated microsensors.

Conclusions:

• The resistive-pulse method with quartz nanochannels is a viable technique for accurate single particle sizing.
• This electronic sensing approach provides a fast and economical alternative to traditional methods.
• Quartz nanochannels offer a versatile platform that can be integrated with other analytical techniques for comprehensive vesicle analysis.