Композитные матрицы на основе сополиамида и полипиррола для тканевой инженерии

It was demonstrated that conducting polymers can be used in development of bioactive matrices for tissue engineering. The most promising conducting polymer for biomedical applications is polypyrrole. Due to a number of useful properties, polypyrrole can be used in designing “smart” biologically active materials. In order to improve mechanical properties of the composite matrices, aliphatic copolyamide was used. Thin polymeric films were obtained from solution of this copolyamide; the solution was also used in preparation of non-woven fibrous mats by electrospinning. Copolyamide films were modified with pyrrole in the process of its oxidative polymerization to give the desired composite matrices. The obtained samples demonstrated suitable performance characteristics and a sufficient conductivity level for cell technologies. In vitro experiments showed that the matrices based on copolyamide and polypyrrole provide good survivability, adhesion and proliferation of human dermal fibroblasts.

Strategies to Tune Electrospun Scaffold Porosity for Effective Cell Response in Tissue Engineering

Tissue engineering aims to develop artificial human tissues by culturing cells on a scaffold in the presence of biochemical cues. Properties of scaffold such as architecture and composition highly influence the overall cell response. Electrospinning has emerged as one of the most affordable, versatile, and successful approaches to develop nonwoven nano/microscale fibrous scaffolds whose structural features resemble that of the native extracellular matrix. However, dense packing of the fibers leads to small-sized pores which obstruct cell infiltration and therefore is a major limitation for their use in tissue engineering applications. To this end, a variety of approaches have been investigated to enhance the pore properties of the electrospun scaffolds. In this review, we collect state-of-the-art modification methods and summarize them into six classes as follows: approaches focused on optimization of packing density by (a) conventional setup, (b) sequential or co-electrospinning setups, (c) involving sacrificial elements, (d) using special collectors, (e) post-production processing, and (f) other specialized methods. Overall, this review covers historical as well as latest methodologies in the field and therefore acts as a quick reference for those interested in electrospinning matrices for tissue engineering and beyond.

Decellularized extracellular matrices for tissue engineering applications

Decellularization removes cellular antigens while preserving the ultrastructure and composition of extracellular matrix (ECM). Decellularized ECM (DECM) scaffolds have been widely used in various tissue engineering applications with varying levels of success. The mechanical, architectural and bioactive properties of a DECM scaffold depend largely on the method of decellularization and dictate its clinical efficacy. This article highlights the advantages and challenges associated with the clinical use of DECM scaffolds. Poor mechanical strength is a significant disadvantage of some DECM scaffolds in the repair of load-bearing tissues as well as critical-size defects, where long-term mechanical support is required for the regenerating tissue. Combining DECM scaffolds with synthetic biocompatible polymers could provide a useful strategy to circumvent the issues of poor mechanical stability. This article reviews studies that have combined DECM scaffolds from various tissues with synthetic polymers to create hybrid scaffolds using electrospinning. These hybrid scaffolds provide a mechanical backbone while retaining the bioactive properties of DECM, thus offering a significant advantage for tissue engineering and regenerative medicine applications.