Fabrication of Nanocomposites Complexed with Gold Nanoparticles on Polyaniline and Application to Their Nerve Regeneration

Abstract

Electrically conductive materials can stimulate stem cells through electric shock and thereby contribute to the regulation of cell proliferation and differentiation. Recently, polymer–metal complexes composed of polyaniline and gold nanoparticles have emerged as novel candidates for use in regenerative medicine. By mixing two different materials, such composites maximize the benefits while alleviating the disadvantages of using either material alone. Based on their excellent conductivity, these complexes can be applied to nerve regeneration using stem cells. In this study, we investigated a method for producing hybrid nanocomposites by complexing gold nanoparticles to polyaniline and tested the resultant composites in a model of nerve regeneration. We manipulated the shape, size, and electrical conductivity of the hybrid composites by compounding the component materials at various ratios. The most efficient nanocomposite was named conductive reinforced nanocomposites (CRNc’s). When the CRNc was delivered directly to cells, no cytotoxicity was observed. After the intracellular delivery of the CRNc, the stem cells were electrically stimulated using an electroporator. As a result of performing mRNA-sequencing (Seq) analysis after electrical stimulation (ES) of the CRNc-internalized cells, it was confirmed that the CRNc-internalized cells have a pattern similar to that of the positive group-induced neuron cells. In particular, microtubule-associated protein 2 is more than twice that of the control group (negative control), and the nerve fiber protein is strongly expressed as in the positive control group. In addition, we verified that neural differentiation progressed by monitoring the growth of neurites from stem cells. Together, these findings show that the CRNc can be used to induce the formation of neuron-like cells by applying ES to stem cells.

Zero‐valent iron nanoparticles containing nanofiber scaffolds for nerve tissue engineering

“…The most common method is the addition of carbon nanotubes into the matrix (Jahromi et al, 2020; Sun et al, 2020; Zhang et al, 2015). Similar studies have been performed with gold nanoparticles, which also have excellent electrical conductivity supporting neuronal development (Kim et al, 2020). However, similar to carbon structures, their systemic toxicity due to the nondegradability of these nanostructures is still controversial (Chen, Hung, Liau and Huang, 2009).…”

Anisotropic scaffolds for peripheral nerve and spinal cord regeneration

“…Native axons are subject to cyclic electric impulses in order to transfer information. Therefore, appropriate electrical stimulation for cells encapsulated in the scaffolds and host neurons and glia is speculated to promote axon survival and migration [ 220 , 221 ]. Dong et al incorporated graphene into electrospun fibrous scaffolds, and they found that electrical stimulation could accelerate cell migration and promote neurotrophic factor secretion in vitro as well as enhance sciatic nerve regeneration and functional recovery after implantation [ 222 ].…”

Hybrid Nanosystems for Biomedical Applications

“…Metallic nanoparticles such as AuNPs have been also able to endow electrical conductivity to the polymer matrices for regulation of neural cell differentiation. Hybrid nanocomposites based on AuNP complexes with polyaniline enabled electrical stimulation . Particularly, microtubule-associated BMP-2 was prominently expressed, and the stimulation process led the neurites to grow from the stem cells.…”

“…Hybrid nanocomposites based on AuNP complexes with polyaniline enabled electrical stimulation. 359 Particularly, microtubule-associated BMP-2 was prominently expressed, and the stimulation process led the neurites to grow from the stem cells. Peripheral nerve regeneration can be also enabled by layered electrospun scaffolds based on Fe 3 O 4 magnetic nanoparticles and melatonin.…”