Abstract: A composition for delivering an agent to a cell, comprising a bispecific affinity reagent and a pH-responsive, membrane destabilizing polymer. The bispecific affinity reagent may include a first affinity reagent covalently linked to a second affinity reagent, wherein the first affinity reagent binds to a molecule on the surface of a cell, and the second affinity reagent binds to an intracellular target.

Abstract: Provided herein are polymeric carriers suitable for the delivery of polynucleotides (e.g. oligonucleotides) and/or other therapeutic agents into a living cell.

Abstract: Described herein are copolymers, and methods of making and utilizing such copolymers. Such copolymers have at least two blocks: a first block that has at least one unit that is hydrophilic at physiologic pH, and a second block that has hydrophobic groups. This second block further has at least one unit with a group that is anionic at about physiologic pH. The described copolymers are disruptive of a cellular membrane, including an extracellular membrane, an intracellular membrane, a vesicle, an organelle, an endosome, a liposome, or a red blood cell. Preferably, in certain instances, the copolymer disrupts the membrane and enters the intracellular environment. In specific examples, the copolymer is endosomolytic.

Abstract: Polymer bioconjugate having a RNAi agent covalently coupled to the alpha or omega end of a pH-dependent membrane-destabilizing polymer.

Abstract: Provided herein are micellic assemblies comprising a plurality of copolymers. In certain instances, micellic assemblies provided herein are pH sensitive particles.