Fabrication of polydopamine nanoparticles knotted alginate scaffolds and their properties

Abstract

Polydopamine (PDA) can greatly affect polymer's properties, due to the chemical and physical interactions between the polymers and PDA. In this study, PDA was demonstrated to adjust the pore structures and increase the mechanical properties of alginate hydrogel‐based cartilage tissue scaffolds. Dopamine modified alginate (Alg‐DA) was firstly synthesized by modification of Alg with DA. Alg‐DA interacted with preprepared PDA nanoparticles and further crosslinked with calcium ions (Ca2+) to form the hydrogel scaffold (Alg‐DA/PDA). The Alg‐DA/PDA scaffold combined multiple advantageous features, including continuous pore structure, high level of porosity, well mechanical properties, good biocompatibility and appropriate cycle life of degradation. Moreover, it could provide an optimized forming environment for hydroxyapatite (HAp) by mineralization process, thus accelerating cartilage repair. The improved performances were mainly ascribed to physical enhancement of the PDA nanoparticles and crosslinking points among the polymers and catechol groups in DA. These findings might offer a guideline for fabricating robust biocompatible cartilage tissue scaffold. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 3255–3266, 2018.

Preparation and physicochemical properties of an injectable alginate-based hydrogel by the regulated release of divalent ions via the hydrolysis of d-glucono-δ-lactone

“…The peak observed at 1526 cm –1 in the FTIR spectrum of Alg–DA corresponded to the –NH– of –CONH–; these peaks were not observed in the FTIR spectrum of Alg. 11 All the above characterization results demonstrated the successful grafting of catechol moieties.…”

“…Therefore, the modification of dopamine is key to improve mechanical properties, which is related to three reactions in the formation of the hydrogel of modified sodium alginate: (i) the interaction between divalent ions and alginate, (ii) the hydrogen interaction between alginate and catechol groups, and (iii) the covalent and noncovalent bonds between the catechol groups in dopamine. 11…”

“…Hence, the modification of alginate has been widely carried out for improving its properties by its combination with various molecules such as growth factors, 9 peptides, 10 and small molecule monomers. 11 Alginate also can be gelled by cross-linking with cations, enzymes, and Schiff bases.…”

Preparation and properties of dopamine‐modified alginate/chitosan–hydroxyapatite scaffolds with gradient structure for bone tissue engineering

“…Fabrication of Alg-DA/QCHA gradient scaffolds DA-modified Alg (Alg-DA) was prepared according to our previous research 20 and detailed in the Supporting Information. An amount of 0.6 g Alg-DA was dissolved in PBS buffer (pH = 6.0) with a concentration of 3% (w/v).…”

“…9,11,18,19 In our work, we had demonstrated an Alg/polydopamine scaffold with enhanced mechanical and biological properties for bone repairing materials. 20 Unfortunately, in these previous reports, the mechanical as well as other properties are still dissatisfied with the clinical application.…”