Separation of selected anticancer drugs using superheated water as the mobile phase

Six anticancer drugs have been eluted on a polystyrene-divinylbenzene (PS-D VB) column with buffered superheated water as the mobile phase. The tempera ture range studied was from ambient temperature up to 160 degreesC, and the pH of the water was adjusted to 11.5 and 3.5 with phosphate buffer. It was possible to separate the substances 5-fluorouracil (5-FU), methotrexate (M TX), 7-hydroxymethotrexate (7-OH-MTX), and etoposide (VP-16) in one chromat ographic run. The separation of these substances was optimized when adjusti ng the pH from 11.5 to 3.5, resulting in a total elution time of less than 13 min. Furthermore, retention factors of all of the investigated substance s were measured at different temperatures and pH values.