Nanofracture on fused silica microchannel for Donnan exclusion based electrokinetic stacking of biomolecules

摘要: Due to Donnan exclusion, charged molecules are prohibited from passing through a channel of electrical double layer scale (nanometers), even though the smaller than lowest dimension channel. To employ this effect for on-chip pre-concentration, an ion nanometer has be introduced. Here we introduced simple method generating fracture (11–250 nm) directly on commercially available open tubular fused silica capillary, and chip comprised capillary with nanofracture was prepared. A ring-disk model derived which width can easily characterized online without any damage chip, result validated by scanning electron microscope (SEM). The fractures used as nanofluidic interface exhibiting obvious concentration polarization high current flux. On-chip electrokinetic stacking SYBR Green I labeled λDNA inside successfully demonstrated, factor close amplification rate polymerase chain reaction (PCR) achieved within 7 min. is inexpensive easy prepare in common chemistry biochemistry laboratories limitations expensive microfabrication facilities sophisticated expertise. More applications could found enhancing detectability based microfluidic analytical systems analysis low concentrated species.