Isfahan University of Technology
Question
Asked 15th Jun, 2018
How can I use sample which melted before freeze drying?
I made self-aggregated nanoparticles using Polysialic acid backbone and after diaylsis in DW, freezed them at -190 ℃.(liquid nitrogen)
Then freeze drying at -50℃.
In this morning, I got rid of my samples from the freeze dryer and found that samples were not perfectly dried. A little of ice in tube was melted with dried nanoparticles.
How can I use those samples?
1. Freeze rest of sample at -190℃ and drying again. And use them
2. Freeze rest of sample at -190℃ and drying again. Mix dried particles with organic solvent and dialysis in DW.
Help me! X(
Most recent answer
Before doing the test, prepare some prototypes with different treatments in various cryogenic circumstances and try to get experiment using those. Among that, do select the best result of them and consider the same as a basis for the original examples. However, the temperature setting of the freeze drier should be frequently checked to prevent any probably error during the test.
2 Recommendations
All Answers (5)
French National Institute for Agriculture, Food, and Environment (INRAE)
Rzfreeze (eventually with a little bit of added water) and try again, talking care that the freeze-drying in working adequately (maybe input a bit o fheat in your samples to facilitate end of freeze-drying)
it may be due to freeze drier warm up time. if you have extra sample try it using another freeze drier
Isfahan University of Technology
Before doing the test, prepare some prototypes with different treatments in various cryogenic circumstances and try to get experiment using those. Among that, do select the best result of them and consider the same as a basis for the original examples. However, the temperature setting of the freeze drier should be frequently checked to prevent any probably error during the test.
2 Recommendations
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References
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