Abstract: With reference to the literature, a quick, accurate and simple method was developed for the determination of encapsulation efficiency in polyphase liposome (PL), based on the separation of the free drug molecules from PL on a minicolumn of sephadex G-25. It was observed that 22% of the total amount of MTX in the system had been entrapped in PL. In release test, it was found that MTX could be passively released from the internal compartments of the particles, but could not be taken up by them, regardless of long term storage at room temperature or being heated at higher temperatures.