Patent ID: 8853325

Claim:
A conjugate having the following structure: wherein: POLY is CH 3 O—CH 2 CH 2 —O—(CH 2 CH 2 O) n-1 —CH 2 CH 2 — and n is 3 to about 4,000; X′ is —O—; z′ is an integer from 2 to about 21; R 1 , in each occurrence, is independently H or an organic radical selected from the group consisting of alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, aryl, and substituted aryl; R 2 , in each occurrence, is independently H or an organic radical selected from the group consisting of alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, aryl, and substituted aryl; and —“NH-biologically active agent” represents a biologically active agent comprising an amino group, and further where the following apply: when POLY is linear: (a) the total number of carbonyls present in the polymer is 0 or 2 or greater except when X′ comprises one or more contiguous (—CH 2 CH 2 O—) segments, and (b) when X′ is oxygen or comprises at least one (—CH 2 CH 2 O—) segment and z′ is from 2 to 12, then at least one of R 1 or R 2 in at least one occurrence is an organic radical as defined above, when POLY is branched, (c) either (i) at least one of R 1 or R 2 in at least one occurrence is an organic radical as defined above or (ii) X′ includes —(CH 2 CH 2 O) b — where b is from 1 to about 20 in the instance where POLY comprises a lysine residue, and (d) when POLY possesses two polymer arms, then neither polymer arm comprises oxygen as the only heteroatom in the instance where POLY comprises “C—H” as a branch point.