These columns permit a simple, one stage clean-up as part of a methodology to determine pesticides in many organic matrices. The higher molecular weight fractions such as lipids, polymers, natural resins and dispersed high molecular weight components are easily eliminated in the GPC analysis.

• High sample loading ensures effective trace analysis
• Simple clean-up procedure saves sample preparation costs
• Optimised particle size distribution provides high resolution

Preparative GPC for soil extract clean-up is described in EPA Method 3640A using 300×25 mm and 150×25 mm columns to give higher sample loading and fraction yields, which is particularly useful for low levels of pollutants. Low pore size EnviroPrep columns are ideal for this method. The columns have 10 µm particles with 100 Å pore sizes for high resolution, with an exclusion limit of 4000 MW. The preparative columns offer good resolution and high loading through optimization of the particle size distribution.