What is Retention time?

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Retention time (RT) is a measure of the time taken for a solute to pass through a chromatography column.

Retention time (RT) is calculated as the time from injection to detection.

The RT for a compound is not fixed as many factors can influence it even if the same instrument and column are used. 

 These include:
  • The flow rate
  • Temperature differences in the oven and column
  • Column degradation
  • Column length

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