or increasing the contrast between the more turbid encapsulated vs non-encapsulated HPTS by placing a piece of paper behind the column can help distinguish the HPTS encapsulated vesicles. The vesicles should be clearly identifiable during elution through the column as a milky green suspension, while the free HPTS is a bright green solution. In this regard, it is important only to collect the required volume of vesicles suspension, minimising the volume of eluent taken before and after.