High modulus, enzyme-degradable poly(trimethylene carbonate)–peptide biohybrid networks formed from triblock prepolymers

Abstract

Biohybrid networks have the potential to have stiffnesses equivalent to that of native soft connective tissues as well as cell-mediated degradation behavior.

Stimuli‐Responsive Depolymerization of Poly(Phthalaldehyde) Copolymers and Networks

“…[24,[26][27][28][29]31,33] There are many examples of degradable cross-links incorporated within networks, the degradation of which are controlled by various applied stimuli. [33][34][35][36][37][38][39] In addition to the development of labile networks by engineering degradable crosslinks, some networks are degraded by bond cleavage within the backbone itself, rather than degradation of the individual cross-links. [34,[40][41][42][43] Herein, the copolymerization of phthalaldehyde with asymmetric allyl phthalaldehyde is explored followed by crosslinking via a thiol-ene photopolymerization with a multifunctional thiol and then the degradation of the cross-linked networks via triggered self-immolation (Scheme 1B).…”

In vivo degradation behavior of enzyme-degradable poly(trimethylene carbonate)-based biohybrid networks of varying water content

“…Prepolymer and initial network characterization A target average PTMC block length of 8 repeating TMC units was chosen for each prepolymer, to provide a prepolymer with appreciable water solubility to facilitate degradation [17]. This PTMC block length was achieved for the VS-PTMC-MA, while an average block length of 9 TMC units was obtained for the VS-PTMC-PEG-MA.…”

“…Heterobifunctional PTMC and PEG-PTMC were synthesised, fractionated, and characterized as described previously [17]. Briefly, PTMC was synthesized by ring-opening melt polymerization of TMC using 2-((2-vinylsulfonyl ethyl)thio)ethanol as initiator and stannous 2-ethylhexanoate as catalyst, and then methacrylated by reaction of methacryloyl chloride with the terminal hydroxyl group.…”

“…Following crosslinking via free radical polymerization of the methacrylate end groups, networks formed from these prepolymers had instantaneous compressive moduli ranging from 1.1 to 10.3 MPa, depending on the water solubility of the prepolymer used to form the network, with higher moduli produced from crosslinking prepolymers of lower water solubility [17]. In the presence of collagenase type II in vitro, these networks degraded via surface erosion through cleavage of the MMP-sensitive peptides in the presence of collagenase, with faster degradation observed for networks with greater water content.…”

Rational design of poly(peptide-ester) block copolymers for enzyme-specific surface resorption

“…13 The use of MMP-specific peptide sequences to control spatial and temporal degradation [14][15][16][17] is most commonly used in hydrogels due to the water-swollen network increasing accessibility of the peptide sequence to water-soluble enzymes. [18][19][20][21] Recent studies have demonstrated incorporation of bioactive peptide into nylons, 22 however, the use of enzyme-sensitive peptides to control resorption of high molecular weight thermoplastics remains unreported. Zorn and colleagues polymerized oligopeptide segments into polyurethanes 23 for the purpose of improving polymer biodegradation.…”