J Biomed Mater Res A. 2018 Apr 10. doi: 10.1002/jbm.a.36428. [Epub ahead of print]

A collagen based cryogel bioscaffold coated with nanostructured polydopamine as a platform for mesenchymal stem cell therapy.

Razavi M¹, Hu S¹, Thakor AS¹.

Abstract

Cryo-hydrogels (cryogels) are polymer hydrogels formed at sub-zero temperatures. Bioscaffolds created from cryogels have interconnected macropores which allow for cell migration, tissue-ingrowth, unhindered diffusion of solutes and mass transport of therapeutics. In this study, we developed collagen based cryogel bioscaffolds and coated them with polydopamine using a simple two-step technique. Cryogel bioscaffolds were synthesized by collagen crosslinking at -20°C and exhibited a macroporous interconnected architecture with 75±3% porosity. Two groups of pore sizes were observed: 300±50 µm and 30±10 µm in diameter. The addition of a polydopamine coating to cryogel bioscaffolds was confirmed using composition analysis. This resulted in a 41±5% decrease in water uptake, 81±10% decrease in swelling rate and 12±3% decrease in their degree of dissolution (P<0.05), with a 48±2% increase in stiffness and 57±5% increase in compressive strength (P<0.05). Seeding adipose tissue-derived mesenchymal stem cells (AD-MSCs) into polydopamine coated-cryogel bioscaffolds resulted in cells demonstrating a 52±4% increase in viability and 33±3% increase in proliferation when compared to AD-MSCs seeded into uncoated-cryogel bioscaffolds (P<0.05). In summary, our novel polydopamine coated-cryogel bioscaffold represents an efficient and low-cost bioscaffold platform to support MSC therapies. This article is protected by copyright. All rights reserved.