Rapidly Cross-Linkable DOPA Containing Terpolymer Adhesives and PEG-Based Cross-Linkers for Biomedical Applications

Abstract

A new three-component bio-inspired adhesive was synthesized that is a terpolymer composed of a water-soluble segment, an interfacial adhesion segment, and a cross-linking segment. Strong wet adhesion properties are obtained utilizing a 3,4-dihydroxy-L-phenylalanine (DOPA) moiety. Poly(acrylic acid) provides high water solubility due to strong ionic interactions with water. An acrylic acid N-hydroxysuccinimide ester (NHS) was included in the adhesive polymer to allow rapid cross-linking with thiolterminated, 3-armed poly(ethylene glycol) cross-linking agents. The thiol terminal poly(ethylene glycol) was designed to be bulky to avoid possible penetration of molecules to the cell and tissue. The NHS and thiol groups react within 30 s to form covalent bonds. This design allows for rapid optimization of properties for specific applications. Lap shear strength tests on wet porcine skin demonstrated a 190% increased value in adhesion strength for adhesives having the DOPA moiety. After cross-linking, adhesion was enhanced by 450% over poly(acrylic acid-co-acrylic acid NHS) and was 240% higher than un-cross-linked poly(acrylic acid-coacrylic acid NHS-co-N-methacryloyl-3,4-dihydroxyl-L-phenylalanine). Rheology studies show adhesive viscosity drops significantly at high shear rates, demonstrating its potential to be injected via syringe. The cross-linked adhesive displayed much stronger mechanical properties and higher elastic and viscous moduli than an un-cross-linked adhesive model. Furthermore, the cross-linked adhesive has enhanced moduli near body temperature (38 °C) as compared to room temperature (23 °C), increasing the applications as a biomedical adhesive.

Bioinspired dopamine-conjugated polyaspartamide as a novel and versatile adhesive material

“…Typically, 0.05 g of a Poly AspAm (DOPA/EA) un-adhesive powder was mixed with 0.05 mL of DI water to form a very sticky paste-like glue, as shown in Figure 5. Because the strong hydrogen-bond formation in the polymer can induce intensive aggregation and chain entanglement, limiting the solubility in water, the polymer did not dissolve in water even after prolonged exposure [28]. To quantify the adhesion behavior, a widely-used lap shear test method was employed.…”

“…Because it is similar to the human dermis, porcine skin is commonly used for adhesive testing of biomedical applications [28]. Figure 9 represents a typical adhesion test set-up, where two pieces of wet porcine skin are prepared (the left image of Figure 9).…”

“…Researchers have been looking for inspiration from mussels to produce bio-inspired wet adhesives for application as biomedical adhesives [3,[25][26][27]. Chung and Grubbs described newly designed DOPA-containing terpolymer adhesives that were prepared by the polymerization of three vinyl monomers: acrylic acid (AA), acrylic acid N-hydroxysuccinimide ester (AANHS), and N-methacryloyl-3,4-dihydroxyl-L-phenylalanine (MDOPA), and suggested that these materials could represent clinically-useful biomedical adhesives [28]. When the DOPA moiety was introduced into the adhesives, the adhesion strength increased by 190% during lap shear tests on wet porcine skin.…”

Breath Figures of Nanoscale Bricks: A Universal Method for Creating Hierarchic Porous Materials from Inorganic Nanoparticles Stabilized with Mussel‐Inspired Copolymers

“…N ‐(3,4‐dihydroxyphenethyl)methacrylamide (DMA) was prepared from dopamine hydrochloride and methacrylate anhydride according to the literature . DMA was used as a monomer having a catechol group . The amphiphilic copolymer (polymer 1, Scheme ), which contained the catechol group, was synthesized from DMA (2.78 × 10 –3 mol) and N ‐dodecylacrylamide (DAA, 22.4 × 10 –3 mol) by free‐radical polymerization (for details, see Supporting Information).…”

Hydrophobicity‐enhanced adhesion of novel biomimetic biocompatible polyaspartamide derivative glues

“…For bioadhesive materials and applications, nontoxicity is as important as high adhesion performance. Nowadays, a wealth of reports has been published on a variety of potential bioadhesives using porcine skin as the substrate due to its similarity to the human dermis . Fan et al .…”