Polymer-protein conjugates represent an emerging union between biology and materials science.  These hybrid materials consist of one or more synthetic polymers covalently joined to one or more naturally derived protein fragments.  Due to their partially synthetic, partially biological origin, the resulting conjugates display unique properties: the synthetic polymer block endows the material with enhanced stability in vivo while the biological block allows the conjugate to interact with its biological surrounding, often leading to therapeutic effects.  In their feature article, Marcus Weck (Molecular Design Institute, New York University) and coworkers survey recent applications as well as future challenges of polymer-protein conjugates, particularly as they relate to emerging biomedical research.

Since the first polymer-protein conjugate was reported in the late 1970s – several poly(ethylene glycol) (PEG) chains attached to a protein, which masked the protein in the body – research in this field has evolved rapidly, leading to several PEG-conjugated therapeutics approved by the US Food and Drug Administration (FDA).  Beyond PEG-conjugated therapeutics that treat certain diseases, current research also focuses on the synthesis of hybrid materials that can be tailored to specific applications including drug delivery, tissue engineering, and antimicrobial use.  By supporting small protein fragments on a polymer scaffold, more complex biomimetic interactions can be achieved.  Research efforts also utilize the protein segments as biocompatible building blocks for new architectures, enabling the synthesis of constructs responsive to biological stimuli.  These efforts have culminated in the synthesis of complex, three-dimensional architectures exhibiting behavior that mimics cellular function.

Polymer-protein conjugates make for intriguing additions to the biomedical chemist’s tool box.  These hybrid materials can lead to new personalized therapies with fewer side effects.