Figure 2
From: Immunological assay using a solid-state pore with a low limit of detection
Measurements of polystyrene beads transported by hydraulic pressure and electrophoresis. (a) Ionic current–time profile of 600-nm polystyrene beads obtained by solid-state pore measurement. The vertical axis is the amount of change in decreasing ion current. Ip and td indicate the maximum current value and current duration, respectively. (b) Ionic current–time waveforms of 100 polystyrene beads with different diameters (ϕ). (c) Bead size dependence of the Ip histogram. (d) The Ip histogram of mode current versus bead size. More than 1000 waveforms were obtained for each bead size. Error bars represent 1× SD. (e) Dependence of pulse frequency on bead concentration. Polystyrene beads with diameters of 300, 500, and 600 nm were measured with three solid pore modules, respectively. Error bars represent 1× SD. (f) Bead size dependence on pulse frequency. Red, blue, and green indicate bead concentrations of 2 × 109 beads/mL, 5 × 108 beads/mL, and 5 × 107 beads/mL, respectively. The three colored dotted lines indicate the saturation pulse frequency at each bead concentration.
