Oh!! Ghost peaks during HPLC analysis

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Though this is funny word 'Ghost' but after all this is also one of the major issue during HPLC analysis. There are many factors which gives rise to such unidentified peaks. Some of important factors are mentioned below:

1) Late eluting peaks: During analysis many times late eluting peaks are found in which they interfere in principle peak in subsequent injections. This can be solved by increasing the run time.

2) Contamination: It sometimes happens that due to some contamination ghost peak used to found during analysis. To handle such situations Ghost buster columns are available in market which can be used. It looks like shown in below image:


3) Water Quality: While preparing mobile phase water quality is not proper then it may give rise to ghost peaks. Such situation should be handled by using either Milli Q grade water or HPLC grade water. 

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