High Performance Liquid Chromatography broad peak causes and solutions for this problem.
Cause Solution
Analytes eluted early due to sample overload | Dilute sample 1:10 and reinject |
Detector-cell volume too large | Use smallest possible cell volume consistent with sensitivity needs; use detector with no heat exchanger in system |
Injection volume too large | Decrease solvent strength of injection solvent to focus solute; inject smaller volume |
Large extra column volume | Use low- or zero-dead-volume endfittings and connectors; use smallest possible diameter of connecting tubing (<0.10> |
Mobile-phase solvent viscosity too high | Increase column temperature; change to lower viscosity solvent |
Peak dispersion in injector valve | Decrease injector sample loop size; introduce air bubble in front and back of sample in loop |
Poor column efficiency | Use smaller-particle-diameter packing, lower-viscosity mobile phase, higher column temperature, or lower flow rate |
Retention time too long | Use gradient elution or stronger isocratic mobile phase |
Sampling rate of data system too low | Increase sampling frequency |
Slow detector time constant | Adjust time constant to match peak width |
Some peaks broad - late elution of analytes retained from previous injection | Flush column with strong solvent at end of run; end gradient at higher solvent concentration |
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