Abstract
Some sixty biological stains of widely varying type have been subjected to gel filtration chromatography in columns of Sephadex LH-20 (Pharmacia, Uppsala) resin swollen by dimethylformamide saturated with NaCl. Most dyes contained more than one coloured constituent. Measures of their molecular weights were obtained. The use of the method for analysis was as effective as other common chromatographic or electrophoretic procedures but was technically simpler. Preparative use of the method merely involved using a larger column of gel, though occasionally use of ethanol as solvent gave better resolutions and did provide easier recovery of separated dyes.