Technology
DEP-Well Technology uses dielectrophoresis (DEP) to manipulate and characterise particles. In contrast to electrophoresis, which uses a homogeneous DC electric field to move charged particles, dielectrophoresis uses a highly inhomogeneous AC field to manipulate particles. This inhomogeneous field leads to an imbalance of coulomb forces within a particle and thereby exerts a force on the particle. Depending on the properties of the particle, the strength and direction of this force at different frequencies can be used to extract the information about the electric properties of the particle. This can be used to either characterise or to separate particles, cells or bacteria. DEP-Well technology uses three-dimensional well electrodes. By using inexpensive lamination technology to fabricate the devices, DEP can be performed in a highly automated and parallel manner.
Dielectrophoresis
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Dielectrophoresis is an electrostatic effect that occurs in highly inhomogeneous electric fields (e.g. close to the tip of a needle or the edge of an electrode). In contrast to electrophoresis (that uses attraction between opposing charges), dielectrophoresis uses an inhomogeneous electric field to polarise the particle, allowing far more information to be extracted. More>> |
DEP-Well
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Traditionally DEP was performed using micro fabricated devices that use thin metal films on a glass base as electrodes. These devices needed to be made using sophisticated microfabrication technologies and were essentially flat. This made them very difficult to handle in a modern laboratory. DEP-Well electrodes improve the situation significantly by effectively taking DEP into the third dimension. More>> |
Cell and Particle Characterisation
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For particle characterisation, use DEP-Well devices with closed bases. Samples are contained inside the wells and monitored by a reader from above or below. Compared to conventional micro-fabricated devices, the evaluation becomes much simpler since the cells are either attracted or repelled from the wall. More>> |
Spectroscopy
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A DEP-Spectrum is a "fingerprint" of the electrical properties of the cell. It is recorded at data points spaced over a range of frequencies 1kHz and 20MHz. Once these data are obtained, computer analysis allows the electrical properties to be extracted. This analysis provides a significant amount of information about the electrophysiology of the cells. More>> |
Separation
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DEP-Well separators are perforated sheets of electrode laminate withenergising electrodes striped along the holes. This allows a suspension of particles to flow through the sheet similar to a filter paper. However, unlike filter paper, particles are separated by different electrical properties, not size. This allows separating particles of similar size and surface properties. More>> |