Poly(2-oxazoline)s as Stimuli-Responsive Materials for Biomedical Applications: Recent Developments of Polish Scientists

Abstract

Poly(2-oxazoline)s are the synthetic polymers that are the products of the cationic ring-opening polymerization (CROP) of 2-oxazoline monomers. Due to their beneficial properties, from which biocompatibility, stealth behavior, high functionalization possibilities, low dispersity, stability, nonionic character, and solubility in water and organic solvents should be noted, they have found many applications and gained enormous interest from scientists. Additionally, with high versatility attainable through copolymerization or through post-polymerization modifications, this class of polymeric systems has been widely used as a polymeric platform for novel biomedical applications. The chemistry of polymers significant expanded into biomedical applications, in which polymeric networks can be successfully used in pharmaceutical development for tissue engineering, gene therapies, and also drug delivery systems. On the other hand, there is also a need to create ‘smart’ polymer biomaterials, responsive to the specified factor, that will be sensitive to various environmental stimuli. The commonly used stimuli-responsive biomedical materials are based mostly on temperature-, light-, magnetic-, electric-, and pH-responsive systems. Thus, creating selective and responsive materials that allow personalized treatment is in the interest of the scientific world. This review article focuses on recent discoveries by Polish scientists working in the field of stimuli-responsive poly(2-oxazoline)s, and their work is compared and contrasted with results reported by other world-renowned specialists.

Stimuli-responsive dynamic hydrogels: design, properties and tissue engineering applications

“…For instance, while the addition of a methyl group does not induce a LCST behavior, the incorporation of iso-propyl, cyclo-propyl, and n -propyl moieties in PAOx induces LCST at approximately 35 °C, 30 °C, and 25 °C, respectively. 106,107…”

Detailed Understanding of Solvent Effects for the Cationic Ring-Opening Polymerization of 2-Ethyl-2-oxazoline

“…In the two last decades, poly­(2-ethyl-2-oxazoline) (PEtOx) has received considerable attention in the field of biomedical and pharmaceutical applications, − including polymer–prodrug conjugates, − hydrogels, − and matrix excipients. − Furthermore, hydrolysis of PEtOx affords linear poly­(ethylene imine) (PEI), − which is the “gold standard” among cationic polymer transfection agent for delivery of nucleic acids. − As reproducible synthesis and narrow dispersity (for therapeutics) are key parameters for such biomedical applications, an in-depth understanding of the synthesis of PEtOx via living cationic polymerization is important. In this work, we addressed the question what the best solvent is for the polymerization of EtOx with respect to polymer solubility, monomer reaction rate, and polymer dispersity.…”

Design of Amphiphilic, Biodegradable Functionalized Polyoxazoline Hybrid-Block Graft Copolymers Using Click Reactions

“…Alternatively, iPrOx can polymerize via the cationic ring-opening polymerization (CROP) of the oxazoline ring. 20 The biodegradable product obtained by this method may have pharmaceutical and medical applications. 21 We focus on the synthesis and characterization of modified oxazoline polymers obtained via a CROP mechanism.…”

“…This yields a hydrocarbon chain with oxazoline ring pendants along the polymer. Alternatively, iPrOx can polymerize via the cationic ring-opening polymerization (CROP) of the oxazoline ring . The biodegradable product obtained by this method may have pharmaceutical and medical applications .…”