Peak splitting during HPLC analysis

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Many times peak splitting is observed during HPLC analysis. Majorly there are 3 main impacting factors due to which peak splitting is observed.

1) Contaminated guard column: Usually guard columns are not washed and this gives splitting of peaks when used for long time. This can be solved by reversing the guard column and flushing it with solvents.

2) Partially blocked frits:  This does not come to notice easily but is very important that frits should be timely changed or cleaned. Since coagulated frits will give rise to splitting of peaks.
3) Small uneven void at column inlet: Repack column with the particles or column should be flushed by reversing it. This will definitely give rid of peak splitting.


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