Chromatography Forum

I am working on GC system on a product from last one month, now all of sudden there is negative peaks with same retention time. What could be the problem associated with negative peaks.

I have checked down with polarity, leak test etc. and all the parameters are kept same from past one month.

kishan,

Please give us as much information as possible about your system and analysis parameters and repost this in the Gas Chromatography section.

Among the parameters, be sure to note the type of detector and all gasses used in the GC system.