Drift in the analyte Retention time in HPLC analysis

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Drift in Retention time of Analyte peak during HPLC analysis:

Causes:  There are several reasons of observing drift in Analyte peak in HPLC analysis  like:

a. There is slight leakage in pump due to which RT shift is observed in the chromatogram

b. Insufficient  saturation of HPLC column as every column behaves in different manner and take different time to get saturated

c. Insufficient sonication of Mobile phase which involves solvents like Acetonitrile which requires minimum 15 to 20 mins. of sonication to remove entrapped air bubbles

d. Incorrect selection of column for analysis.

Remedies: 

a. Any type of leakage which might at pump or detector, must be immediately fixed. It might be possible fer rules are not tightened properly which must properly tightened 

b. Column saturation  should be done to get stable baseline. Once it is free from any types of noise, standard injection to be done.

c. Mobile sonication should be done for minimum 20 minutes to avoid any bubbles entrapment in mobile phase.

d. Column selection should always be done as per the exact specification as mention in standard procedure. This will also solve any unknown issues which are manifesting during routine HPLC  analysis. 


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