Reactive vesicle and functional substance-fixed vesicle

A liposome having at least one member selected from the group consisting of an amino group, a hydroxyl group and a thiol group attached to a membrane thereof through an urethane bond, a carbonate bond or a thiocarbonate bond, said liposome additionally comprising, as a vesicle-forming component, one or more phospholipid derivatives represented by the general formula (2):

• ##STR22## in which R.sup.1 C(.dbd.O) and R.sup.2 C(.dbd.O) each represent an aliphatic acyl group having 3-30 carbon atoms and may be identical or different from each other,
• OA represents an oxyalkylene group of 2-4 carbon atoms,
• n indicates the average additional mole number of added oxyalkylene groups and is a positive number of 1-1,000, with the proviso that the oxyalkylene groups may be identical or different from each other and may be added randomly or in a block when n is 2 or higher,
• p is 0 or 1,
• X represents the group ##STR23## wherein q is an integer of 0 to 4 and r is an integer of 1 to 4, M denotes a hydrogen atom or an alkali metal atom and
• Y denotes a residue of a substance.

A drug delivery liposome, comprising

• a liposome composed of liposome-forming components containing one or more reactive phospholipid derivatives represented by the general formula (1) given below and
• a drug contained within the liposome:
• ##STR24## in which R.sup.1 C(.dbd.O) and R.sup.2 C(.dbd.O) each represent an aliphatic acyl group having 3-30 carbon atoms and may be identical or different from each other,
• R.sup.3 denotes a hydrogen atom or a methyl group,
• OA represents an oxyalkylene group of 2-4 carbon atoms,
• n indicates the average addition mole number of added oxyalkylene groups and is a positive number of 1-1,000, with the proviso that the oxyalkylene groups may be identical or different from each other and may be added randomly or in a block when n is 2 or higher,
• p is 0 or 1,
• X represents the group ##STR25## wherein q is an integer of 0 to 4 and r is an integer of 1 to 4 and M denotes a hydrogen atom or an alkali metal atom.

A drug delivery liposome comprising

• a liposome composed of liposome-forming components containing one or more phospholipid derivatives represented by the general formula (2) given below and
• a drug contained within the liposome:
• ##STR26## in which R.sup.1 C(.dbd.O) and R.sup.2 C(.dbd.O) each represent an aliphatic acyl group having 3-30 carbon atoms and may be identical or different from each other,
• OA represents an oxyalkylene group of 2-4 carbon atoms,
• n indicates the average additional mole number of added oxyalkylene groups and is a positive number of 1-1,000, with the proviso that the oxyalkylene groups may be identical or different from each other and may be added randomly or in a block when n is 2 or higher,
• p is 0 or 1,
• X represents the group ##STR27## wherein q is an integer of 0 to 4 and r is an integer of 1 to 4, M denotes a hydrogen atom or an alkali metal atom and
• Y denotes a residue of a substance.