| Clipped from: 07.20.2005 - Engineers create optoelectronic tweezers to round up cells, microparticles |
Engineers create optoelectronic tweezers to round up cells, microparticles
BERKELEY – Rounding up wayward cells and particles on a microscope slide can be as difficult as corralling wild horses on the range, particularly if there's a need to separate a single individual from the group.
But now, a new device developed by University of California, Berkeley, engineers, and dubbed an "optoelectronic tweezer," will enable researchers to easily manipulate large numbers of single cells and particles using optical images projected on a glass slide coated with photoconductive materials.
| Clipped from: IPL: Integrated Photonics Laboratory |
The working principle behind optoelectronic tweezers is light-induced dielectrophoresis. A photosensitive device layer forms "virtual electrodes" upon exposure to light, creating non-uniformities in an applied electric field (Fig. 1). The non-uniform electric field gives rise to a force known as dielectrophoresis: micro- and nanoparticles move as a result of the non-uniformities in the electric field imparting unequal forces on the induced dipole of the particle.
Figure 1:Device structure used in optoelectronic tweezers (OET).
Fig. 13 Spatial control of two cells. (a) Initially, two cells in close proximity are trapped in a single optical box. (b) Separation of the two adjacent cells. (c) Joining of two separated cells. (d–e) Stacking of 2 cells vertically in one single trap.
Sources:
| Clipped from: Lab on a Chip Articles |
Phototransistor-based optoelectronic tweezers for dynamic cell manipulation in cell culture media
Hsan-yin Hsu, Aaron T. Ohta, Pei-Yu Chiou, Arash Jamshidi, Steven L. Neale and Ming C. Wu
| Clipped from: Phototransistor-based optoelectronic tweezers for dynamic cell manipulation in ..... (DOI: 10.1039/b906593h) |
Optoelectronic tweezers (OET), based on light-induced dielectrophoresis, has been shown as a versatile tool for parallel manipulation of micro-particles and cells [...] However, the conventional OET device cannot operate in cell culture media or other high-conductivity physiological buffers [...] In this paper, we report a new phototransistor-based OET (Ph-OET). Consisting of single-crystalline bipolar junction transistors, the Ph-OET has more than 500× higher photoconductivity than amorphous silicon.[...]
Fig. 6 Schematic of the Ph-OET device. Samples are placed in between an ITO-coated glass and the Ph-OET. AC electric field bias is applied between the top ITO electrode and bottom silicon substrate. Optical access is provided through the ITO glass.
Fig. 13 Spatial control of two cells. (a) Initially, two cells in close proximity are trapped in a single optical box. (b) Separation of the two adjacent cells. (c) Joining of two separated cells. (d–e) Stacking of 2 cells vertically in one single trap.
| Clipped from: YouTube - Phototransistor-based optoelectronic tweezers for dynamic cell manipulation in cell culture media |
Sources:
- 07.20.2005 - Engineers create optoelectronic tweezers to round up cells, microparticles
- IPL: Integrated Photonics Laboratory
- Lab on a Chip Articles
- Phototransistor-based optoelectronic tweezers for dynamic cell manipulation in ..... (DOI: 10.1039/b906593h)
- YouTube - Phototransistor-based optoelectronic tweezers for dynamic cell manipulation in cell culture media
