Cold trapping or thermal focussing
- Page ID
- 61213
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Cold trapping occurs when the column temperature is so low compared to the elution temperature of the sample component that they are very strongly retained by the stationary phase. This results in very large k values for the individual analytes.
Cold trapping requires a negative temperature gradient such as will occur in case of a hot injector (split or splitless injector) combined with a low initial oven temperature.