An electrospun nanofiber mat as an electrode for AC-dielectrophoretic trapping of nanoparticles

In order to trap nanoparticles with dielectrophoresis, high electric field gradients are needed. Here we created large area (>mm(2)) conductive carbon nanofiber mats to trap nanoparticles with dielectrophoresis. The electrospun fiber mats had an average diameter of 267 +/- 94 nm and a conductivity of 2.55 S cm(-1). Relative to cleanroom procedures, this procedure is less expensive in creating bulk conductive nanoscale features. The electrospun fiber mat was used as one electrode, with an indium-tin-oxide glass slide serving as the other (separated approximately 150 mu m). Numerical models showed that conductive nanoscale fibers can generate significant field gradients sufficient to overcome Brownian transport of nanoparticles. Our experiments trapped 20 nm fluorescent polystyrene beads at 7 V-rms and 1 kHz. Trapping is further enhanced through simultaneous electrohydrodynamic motion. Overall, this straightforward electrospun fiber mat can serve as a foundation for future use in microscale electrokinetic devices.

Automated summary

By using conductive carbon nanofiber mats, large-scale trapping of nanoparticles can be achieved to overcome Brownian transport. This method is cost-effective compared to traditional cleanroom procedures and can serve as a foundation for microscale electrokinetic devices.