Enhanced microfluidic electromagnetic measurements

摘要

Techniques for enhanced microfluidic impedance spectroscopy include causing a core fluid to flow into a channel between two sheath flows of one or more sheath fluids different from the core fluid. Flow in the channel is laminar. A dielectric constant of a fluid constituting either sheath flow is much less than a dielectric constant of the core fluid. Electrical impedance is measured in the channel between at least a first pair of electrodes. In some embodiments, enhanced optical measurements include causing a core fluid to flow into a channel between two sheath flows of one or more sheath fluids different from the core fluid. An optical index of refraction of a fluid constituting either sheath flow is much less than an optical index of refraction of the core fluid. An optical property is measured in the channel.

主权项

1. A method comprising:
causing a core fluid to flow into a channel between two sheath flows of one or more sheath fluids different from the core fluid, wherein a dielectric constant of a fluid constituting either sheath flow is less than a dielectric constant of the core fluid, and wherein flow in the channel is laminar; determining impedance in the channel based on measurements at a first pair of one or more pairs of electrodes; determining impedance of a particle in the core fluid; and introducing a plurality of uniform particles of known impedance value into the core fluid as an internal control.