Ensemble averaging and digital filtering in chromatography and electrophoresis

Ensemble averaging and digital filtering were implemented for signal-to-noise ratio improvement in the separation techniques of size-exclusion chromatography, immunoaffinity chromatography, capillary zone electrophoresis and capillary ion analysis. Results of ensemble averaging were always greater than statistically predicted. Techniques included five to nine replicate separations and yielded signal-to-noise improvement factors of 2.5 to 9.3. Running-average and time constant (RC)-convolution digital filters yielded increases in the signal-to-noise ratio ranging from zero to twelve. This paper will discuss and illustrate the usage of ensemble averaging and digital filtering in liquid-phase separation techniques.