Experimental Procedures
Transformation on chip protocol:
Preparing for cell transformation
- Set up chip by connecting 0.583mm tubes insulated with paper towels to the heat channels. Use bent metal connectors. Connect tubes to two peristaltic pumps; one for each heating channel. Place a syringe needle in the inlet of the transformation channel and a tube in its outlet. (See image of setup)
- Heat the chip by running water at 65°C and 300mL h-1 through the heating channels.
- Take out 50µL of CaCl2 competent cells from -80°C freezer and thaw them on ice for 5 min.
- Take 10µL of competent cells into a separate tube for negative control.
- Add 0.8µL of DNA (at a concentration of approximately 70 ng µL-1 ) to the remaining 40µL of cells. Incubate cell and DNA suspension for 20 min on ice.
Running the transformation chips
- Flush the cell channel with 2 mL of 75% ethanol with a syringe. Dry the cell channel with air. This cleaning step should be repeated after each transformation to avoid contamination.
- For each transformation: pipette 6µL of cell and DNA suspension into the syringe connector on the chip.
- Push the suspension into the transformation channel by pushing air in with a syringe.
- Fill the transformation channel and heat shock the suspension for 45 sec.
- Push the cell suspension through and collect in an Eppendorf tube filled with 100µL SOB.
- Place the tube on ice immediately.
- Incubate for 1.5 h at 37°C and then spread on an agar plate with the appropriate antibiotic.