Detection of sympathomimetic central nervous stimulants with special reference to doping. II. Comparative study of two adsorption chromatography methods using different XAD resins.

Recoveries of a series of sympathomimetic central nervous stimulants in human urine are measured using either adsorption chromatography on self-filled columns (method A) or with a special resin method suitable for racehorse urine (method B). The Amberlite resins used are XAD-2, XAD-4, XAD-7 and XAD-8 and elution is performed using chloroform. The reported comparative drug extractabilities indicate that in most instances the recoveries follow the sequence XAD-4 greater than XAD-2 approximately XAD-8 greater than XAD-7 using method A. Based on the recovery and purity of the extracts obtained, XAD-8 is preferred for gas chromatographic analysis while XAD-4 is very suitable for thin-layer chromatographic screening work. Comparing the two methods, equally good or better results were obtained with method A for all of the resins studied except XAD-7. Finally, it was found that the effect of refrigerated storage of the resins on the drug extractabilities for central nervous stimulants could be neglected.