Abstract:

We report the uses of resistive-pulse method and quartz nanochannels for the detection and size analysis of single vesicles. Cylindrical shape quartz nanochannels have been used to detect single phospholipid vesicles ranging from 100 to 300 nm and polystyrene nanoparticles ranging from 170 to 400 nm in diameter. Translocations of single vesicles and nanoparticle were detected as individual square current pulses, which could be used to determine particle size. Our results show excellent agreement between the particle/vesicle sizes obtained from nanochannels and those from dynamic light scattering (DLS) and scanning electron microscopy (SEM). This electronic-based method was found to be fast, simple, and used cheap and robust microsensors made in house. The application of a quartz channel might be combined with other analytical methods, such as amperometry and fluorescence microscopy, to yield more complete information about biological and artificial vesicles.

Key words: resistive-pulse method, quartz nanochannels, single vesicles, polystyrene nanoparticles