D E M O N S T R A T E
Demonstrate
Freeze Drying Protocol
- Add 5 ml of sterile LB media and 5ul of chloramphenicol and ampicillin to a culture tube.
- Obtain the desired plate. Take 1-3 colonies from the biosensor cells’ plate with a sterilized inoculating loop. Stir vigorously to ensure colonies are dispensed into solution.
- Place culture tubes on a rack in the incubator. Set to shake and temperature to 36-38 C, and grow overnight.
- Centrifuge liquid culture and discard the supernatant. Resuspend the pellet in 5ml of Microbial Freeze Drying Buffer with tryptic soy broth.
- Aliquot 500ul of the suspension into sterile vials with stopper.
- Turn on the lyophilizer and start the condenser. Set the shelf to 4°C.
- Center the vials on the shelf. Either manually or with programmed controls, freeze the samples down to -40°C. This should take about 30-60 minutes, but it is very dependent upon the lyophilizer. If the rate of freezing can be controlled, a practical rate is to drop the temperature by 1°C per minute. The samples should be visually frozen.
- Let the samples sit at -40°C for 1 hour to complete freezing.
- Turn on the vacuum pump. Within 10-20 minutes, the vacuum should be under 200 millitorr (mtorr).
- After the vacuum is below 200 mtorr, increase the temperature of the shelf for primary drying. The temperature can be up to -15°C. Let continue overnight.
- For second drying, raise the shelf temperature to 20°C and dry for 2 hours.
- With the stoppering mechanism, pit the stoppers on the vacuum. Turn off vacuum.
- Store at 4°C in the dark.