Abstract: A composition suitable for use in diagnostic imaging or as a cell killing agent comprising a chelating residue linked via an amide linkage to a poly(alkylene oxide) moiety, said compisition having a molecular weight of at least 4,500; ##STR1## wherein: Z is a chelating residue;Q is a divalent poly(alkylene oxidylene) moiety having a carbon terminus at R and at L;L represents an amide linkage;E.sup.(b) is one or more counterions each having a charge of b;b is an integer from 1, 2 and 3;n is an integer selected from the group 1, 2, 3 and 4;w is zero or an integer from 1 to 5;M.sup.(+a) is a cation, having a charge of +a;a is an integer from 1 to 4;r is 0 or an integer from 1 to 3, provided that when r is 2-3, each M.sup.(+a) can be the same or different cation;d is the total charge on the chelating residue and is an integer from 0 to 10;d+.SIGMA.(b.multidot.w)+.SIGMA.(a.multidot.r)=O; andR is a capping moiety chosen from the group consisting of hydrogen, hydroxyl, C.sub.1 -C.sub.

Abstract: A composition suitable for use in diagnostic imaging or as a cell killing agent comprising a chelating residue linked via an amide linkage to a poly(alkylene oxide) moiety, said composition having a molecular weight of at least 4,500; ##STR1## wherein: Z is a chelating residue;Q is a divalent poly(alkylene oxidylene) moiety having a carbon terminus at R and at L;L represents an amide linkage;E.sup.(b) is one or more counterions each having a charge of b;b is an integer from 1, 2 and 3;n is an integer selected from the group 1, 2, 3 and 4;w is zero or an integer from 1 to 5;M.sup.(+a) is a cation, having a charge of +a;a is an integer from 1 to 4;r is 0 or an integer from 1 to 3, provided that when r is 2-3, each M.sup.(+a) can be the same or different cation;d is the total charge on the chelating residue and is an integer from 0 to 10;d+.SIGMA.(b.multidot.w)+.SIGMA.(a.multidot.r)=O; andR is a capping moiety chosen from the group consisting of hydrogen, hydroxyl, C.sub.1 -C.sub.