A new small particle packing for faster analysis with high resolution.

The need for fast and efficient separations of complex samples such as pharmaceuticals and biologicals led to the development of fast, efficient, and reproducible 3.5 microns columns. Separations using 3.5 microns column are 30-50% faster at equal plate-count compared to 5 microns columns. The results show that the 3.5 microns columns (100 mm length) give the same efficiency and resolution of drug impurities as the 5 microns columns (150 mm length). For many analytical methods, switching to 3.5 microns columns saves time and reduces costs. Separation methodologies using 5 microns columns are easily modified to accommodate 3.5 microns columns of the same chemistry because efficiency, resolution and sensitivity remain the same. It is shown that 3.5 microns columns have lifetimes comparable to 5 microns columns of the same brand.