*Broad peaks
old mobile phase,Low flow rate,Column overload,Void volume at inlet,too long or too wide Tubing.
*Ghost peaks
Contamination of injector or column,Retained compound from previous injection.
*Negative peaks
Refractive index of mobile phase higher than that of solute,great difference in composition between sample solvent and mobile phase,Mobile phase more absortive than sample components.
*Peak fronting
Column overload,Sample solvent incompatible with mobile phase,Void volume at inlet.
*Rounded peaks
Column overload,Wrong sample solvent.
*Base line noise
Air in mobile phase,detector cell or pump,incomplete mixing,leak,Bad quality mobile phase,detector Cell contamination,Weak detector lamp.
*Peak tailing
wrong column,Sample solvent incompatible with mobile phase,Void volume at inlet.
