Isolation and determination of quaternary ammonium compounds by means of XAD-columns and thin layer chromatography

The potentials of XAD-columns for the isolation of quaternary ammonium compounds from aqueous media have been investigated. When adequate amounts of counter ions (perchlorate, chloride, phosphate, nitrate) were added to the aqueous sample, to the column pretreatment fluid and to the aqueous washing fluid, most quaternary compounds investigated were retained on the column and could be recovered by elution with methanol. Quantitation of decamethonium isolated in this way from urine samples could be performed on silicagel thin layer plates through visualization with iodine, followed by densitometric evaluation. Detection limits were 0.1 microgram/ml. Recoveries at the 1 microgram/ml level were between 80-90% with variation coefficients of less than 10%.