Electrokinetic motion of single nanoparticles in single PDMS nanochannels
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Electrokinetic motion of single nanoparticles in single nanochannels was studied systematically by image tracking method. A novel method to fabricate PDMS-glass micro/nanochannel chips with single nanochannels was presented. The effects of ionic concentration of the buffer solution, particle-to-channel size ratio and electric field on the electrokinetic velocity of fluorescent nanoparticles were studied. The experimental results show that the apparent velocity of nanoparticles in single nanochannels increases with the ionic concentration when the ionic concentration is low and decreases with the ionic concentration when the concentration is high. The apparent velocity decreases with the particle-to-channel size ratio (a/b). Under the condition of low electric fields, nanoparticles can hardly move in single nanochannels with a large particle-to-channel size ratio. Generally, the apparent velocity increases with the applied electric field linearly. The experimental study presented in this article is valuable for future research and applications of transport and manipulation of nanoparticles in nanofluidic devices, such as separation of charged nanoparticles and DNA molecules.
KeywordsElectrokinetic motion Nanoparticles PDMS nanochannels Particle-to-channel size ratio
The authors wish to thank the financial support of the Natural Sciences and Engineering Research Council (NSERC) of Canada through a research grant to D. Li.
Supplementary material 2 (MP4 1219 kb)
- Henry DC (1931) The cataphoresis of suspended particles. Part I. The equation of cataphoresis. In: Proceedings of the royal society of London A: mathematical, physical and engineering sciences. The royal society, pp 106–129Google Scholar
- Li D (2004) Electrokinetics in microfluidics. Academic Press, CambridgeGoogle Scholar