A Guideline for the Synthesis of Amino‐Acid‐Functionalized Monomers and Their Polymerizations

Abstract

Amino acids have emerged as a sustainable source for the design of functional polymers. Besides their wide availability, especially their high degree of biocompatibility makes them appealing for a broad range of applications in the biomedical research field. In addition to these favorable characteristics, the versatility of reactive functional groups in amino acids (i.e., carboxylic acids, amines, thiols, and hydroxyl groups) makes them suitable starting materials for various polymerization approaches, which include step-and chain-growth reactions. This review aims to provide an overview of strategies to incorporate amino acids into polymers. To this end, it focuses on the preparation of polymerizable monomers from amino acids, which yield main chain or side chain-functionalized polymers. Furthermore, postpolymerization modification approaches for polymer side chain functionalization are discussed. Amino acids are presented as a versatile platform for the development of polymers with tailored properties.

Zwitterionic Amino Acid-Derived Polyacrylates as Smart Materials Exhibiting Cellular Specificity and Therapeutic Activity

“…, poly­(ethylene glycol)­s, poly­(cyclic imino ether)­s, and poly­(vinyl pyrrolidine)­s) have gained interest due to their low protein adsorption and high blood circulation times. , While low-fouling properties are advantageous to decrease unwanted cellular interactions, they can also reduce the association with the target tissue and cells. , The introduction of targeting moieties, such as antibodies, peptides, or saccharides, can improve the targetability of these low-fouling polymers; however, they often need to be introduced by postpolymerization modification (PPM), which can lead to tedious material synthesis procedures . One promising strategy to overcome this issue is the incorporation of natural, low-fouling compounds, such as proteinogenic amino acids into polymer chains by the monomer approach . Due to their various functional groups, which are readily available for chemical reactions, amino acids have emerged as suitable candidates for the preparation of polymerizable monomers .…”

“…19 One promising strategy to overcome this issue is the incorporation of natural, low-fouling compounds, such as proteinogenic amino acids into polymer chains by the monomer approach. 20 Due to their various functional groups, which are readily available for chemical reactions, amino acids have emerged as suitable candidates for the preparation of polymerizable monomers. 20 In particular, the α-carboxylic acid and α-amine group of neutral aliphatic amino acids has been exploited for this purpose.…”

Rational construction of polycystine-based nanoparticles for biomedical applications

“…PCys 2 is usually synthesized through the ring-opening polymerization (ROP) of Cys 2 NCA using small or large molecule initiators. 13 The ROP of NCAs is theoretically living, so the synthesized polypeptides with a controllable molecular weight, defined chain length, and narrow distribution can be realized in both high yield and quantity.…”

Dual Thermoresponsive Boc-Lysine-Based Acryl Polymer: RAFT Kinetics and Anti-Protein-Fouling of Its Zwitterionic Form

“…Thus, designing and development of such stimuli-responsive polymers have drawn attention to the polymer scientists because of their ability to mimic biological systems and potential applications in biomedical and biotechnological areas such as drug delivery, − gene delivery, tissue engineering, therapeutics, as well as materials for making bio-fouling surfaces . The best way to synthesize these amino acid-based polymers with controlled molecular weights ( M n s) is to incorporate specific amino acids to polymerizable moieties (e.g., acryloyl, styryl, and so forth), followed by their polymerization via reversible addition-fragmentation chain transfer (RAFT), atom transfer radical polymerization, and so forth. − Postmodification of the presynthesized polymers also offers greater prospects in developing such responsive polymers. − It is worth mentioning that the nature of stimuli-responsiveness of these polymers is mainly governed by the side chain functionality of their constituent amino acids. Also, there are only very few reports of development of multistimuli-responsive amino acid-based homo- and co-polymers. , For example, Mori et al have synthesized a multistimuli-responsive amino acid-based block copolymer nanoparticle by RAFT polymerization of a threonine containing monomer …”