Difference between revisions of "DIY Laser tweezer, cell trap, oligo synthesis"
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For the experiment we need strong lasers found in DVD Burners with speeds 16x and up.<br> | For the experiment we need strong lasers found in DVD Burners with speeds 16x and up.<br> | ||
To know what you have got at hand, the following list is pretty helpful: | To know what you have got at hand, the following list is pretty helpful: | ||
− | [[File:trap_Laser_type.png|none| | + | [[File:trap_Laser_type.png|none|550px|]]<br> |
Source: http://elabz.com/laser-diode-power-output-based-on-dvd-rrw-specs/ | Source: http://elabz.com/laser-diode-power-output-based-on-dvd-rrw-specs/ |
Revision as of 12:54, 2 October 2012
In a short and intense hack sprint we tried to reproduce the laser tweezer as described in the paper of A. Kasukurti, M. Potcoava, S.A. Desai, C. Eggleton, and D. W. M. Marr1,* - found here:
Single-cell isolation using a DVD optical pickup
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3169297/
To do so, a group of bio hackers, micro engineers, artists and theoretical multi dimension algebra mathematician and a few lovely cats met in the FarmLab in Clemens near Lausanne.
Contents
Harvesting the Laser
First we needed to harvest the lasers from old DVD Drives (Digital Versatile Disk).
For the experiment we need strong lasers found in DVD Burners with speeds 16x and up.
To know what you have got at hand, the following list is pretty helpful:
Source: http://elabz.com/laser-diode-power-output-based-on-dvd-rrw-specs/
Powering the Laser
First Notes:
- The schematic in the papaer to power the laser uses an "unusual" pinout of the LM317. Refer to the schematic below rather.
- The suggested current of 350mA for a DVD laser diode is at the upper limit of what most of these laser can take (without extra cooling). So go slowly and expect to blow up your diode at 350 mA (what happend to me)
- Actualy the discription of the diagram in the paper says 420 mA. When I recalculate the current (with R=4 Ohm and UAdj=1.25V (I=UAdj/R) I get a current of only 312 mA. This is probably a good value :-)
- Generaly laser diodes are quite delicate. When they suddenly get less bright then they are in the so called "LED" mode and kaput.
R=4 Ohm (in total)
Pot= 100 Ohm or less.
Mechanical Setup
The objects to move arround
Optical tweezers directed one-bead one-sequence synthesis of
oligonucleotides†
http://www.ncbi.nlm.nih.gov/pubmed/21445444
Interferometry with optical pickups.
Quercioli F, Tiribilli B, Bartoli A.
http://www.ncbi.nlm.nih.gov/pubmed/18073818
A CHEAP 2D FLUORESCENCE DETECTION SYSTEM
FOR μM-SIZED BEADS ON-CHIP
Loes I. Segerink*, Maarten J. Koster, Ad J. Sprenkels, Istvan Vermes and Albert van den Berg
A new DNA chip detection mechanism using optical pick-up actuators
Kyung-Ho Kim, Seung-Yop Lee, Sookyung Kim, Seung-Hwan Lee and Seong-Gab Jeong
http://www.springerlink.com/content/084133p3n5mk1411/