Patent ID: 7417110

Claim:
A water soluble and positively charged biodegradable polyphosphoramidate that is capable of forming a complex with negatively charged bioactive macromolecules in aqueous solutions and comprises the recurring monomeric unit shown in Formula I: wherein R 1 is a divalent aliphatic organic moiety; R 2 and R 3 are each independently selected from the group consisting of hydrogen, alkyl, aryl heteroaryl, heteroalicyclic, cycloalkyl, aralkyl, and cycloalkylalkyl groups; each non-hydrogen occurrence of R 2 and R 3 is substituted with one or more positively charged groups; and n is from 20 to 2,000; wherein when R 1 is —(CH 2 ) a — and one of R 2 and R 3 is hydrogen, the other of R 3 and R 2 is selected from the group consisting of hydrogen, aryl, heteroaryl, heteroalicylcic, cycloalkyl, aralkyl, and cycloalkylaklyl, wherein a ranges from 2 to 6.