Patent ID: 8440816

Claim:
A method of preparing a biologically active conjugate of the formula D-L 1 -(X) p -R(—X′-POLY) q comprising: reacting a branched reactive polymer having the structure Y—(X)p-R(—X′-POLY) q with a biologically active molecule D; wherein: Y is a functional group; R is an aliphatic hydrocarbon having a length of at least three carbon atoms; X′ is —O—; X is a linker of 1 to 10 atoms in length; p is 0 or 1; q is 2 to about 10; L 1 is a linkage resulting from the reaction of a functional group on the linker (X), when present, or on the aliphatic hydrocarbon having a length of at least three carbon atoms (R) of the branched polymer and a functional group of the biologically active molecule; and each POLY is a water soluble and non-peptidic polymer that terminates with a hydroxyl or methoxy group, and further wherein the branched polymer has a molecular weight of about 12,000 Da to about 100,000 Da.