Lack of Sensitivity: Causes and Solutions

                        Possible Cause                                               Solution
 
 
Autosampler flow lines blocked Check flow and clear any blockages
Detector attenuation set too high  Reduce detector attenuation
First few sample injections - sample adsorption in injector sample loop or column Condition loop and column with concentrated sample. 
Injector sample loop underfilled  Overfill loop with sample 
Not enough sample injected  Increase amount of sample inected
Peaks are outside detector's linear range Dilute or concentrate sample to bring detector 
response into linear range
Sample losses during sample preparation  Use internal standard during sample prepartion; optimize sample preparation method 
Sample losses on column See problem: Recovery