Review of Hybrid Materials Based on Polyhydroxyalkanoates for Tissue Engineering Applications

Abstract

This review is focused on hybrid polyhydroxyalkanoate-based (PHA) biomaterials with improved physico-mechanical, chemical, and piezoelectric properties and controlled biodegradation rate for applications in bone, cartilage, nerve and skin tissue engineering. PHAs are polyesters produced by a wide range of bacteria under unbalanced growth conditions. They are biodegradable, biocompatible, and piezoelectric polymers, which make them very attractive biomaterials for various biomedical applications. As naturally derived materials, PHAs have been used for multiple cell and tissue engineering applications; however, their widespread biomedical applications are limited due to their lack of toughness, elasticity, hydrophilicity and bioactivity. The chemical structure of PHAs allows them to combine with other polymers or inorganic materials to form hybrid composites with improved structural and functional properties. Their type (films, fibers, and 3D printed scaffolds) and properties can be tailored with fabrication methods and materials used as fillers. Here, we are aiming to fill in a gap in literature, revealing an up-to-date overview of ongoing research strategies that make use of PHAs as versatile and prospective biomaterials. In this work, a systematic and detailed review of works investigating PHA-based hybrid materials with tailored properties and performance for use in tissue engineering applications is carried out. A literature survey revealed that PHA-based composites have better performance for use in tissue regeneration applications than pure PHA.

Core-Shell Magnetoactive PHB/Gelatin/Magnetite Composite Electrospun Scaffolds for Biomedical Applications

“…As polymer components of magneto-responsive materials, polyethylene glycols, polyacrylamides [ 9 ], polyurethanes [ 10 ], fluorinated polymers [ 11 ], polyesters [ 12 ], and other polymers are used. Among the mentioned polymers, polyhydroxybutyrate (PHB) is of particular interest due to its biocompatibility, piezoelectricity, and ability to biodegrade [ 13 ]. Its degradation inside the body occurs slowly, thus, materials made of PHB are able to support a long-term tissue regeneration [ 14 ].…”

“…The hydrophobic properties of PHB, from the point of view of biomedical application, affect its controlled biodegradation, effective interactions with biological media, cells and different tissues [ 31 , 32 ]. The surface properties of PHB can be improved via various methods summarized elsewhere [ 13 ]. Among the methods known to increase the hydrophilicity of the PHB surface, the most promising is the preparation of blends with natural polymers [ 33 ], in particular, gelatin.…”

Special Features of Polyester-Based Materials for Medical Applications

“…PHB shows high mechanical strength, biocompatibility, and easy processability. The low narrow thermal processing window, lack of toughness, hydrophilicity, and bioactivity are the main drawbacks of PHA [ 50 ].…”

Bioplastic Design using Multitask Deep Neural Networks

“…3,15 Key parameters of these modifications are the numbers of carbons in the mainchain and side-chain (n and m in Figure 1a), and the terminating functional groups of the side-chain (R in Figure 1a). 15,16 For instance, the most widely known PHA, poly-3hydroxybutyrate (P3HB, with n = 1, m = 1, and no R), is brittle and inflexible. 17 As the number of carbon atoms in the backbone increases, the resulting polymers tend to display higher elongation at break ( b ) combined with improved mechanical strength and enhanced tendency for degradability.…”