Bio - Conductive Scaffold Based on Agarose - Polyaniline for Tissue Engineering

Abstract

Architecting novel scaffold for tissue engineering has attracted significant attention. Biomimic scaffolds can enhance cellular activity and tissue regeneration. Conductive scaffold exhibited ameliorated regeneration and tissue repair. In this research, conductive hydrogel based on agarose/polyaniline was synthesized to evaluate hydrogel performance as a novel candidate for tissue engineering. Agarose/polyaniline was synthesized using in -situ oxidative polymerization to achieve conductive hydrogel. Fourier Transform Infrared Spectroscopy (FTIR) was utilized for characterization of the hydrogel. Cyclic voltammetry and conductivity measurement were applied for determining the electro -activity and hydrogel conductivity. Hydrogel conductivity was around 10 to 4 S/cm and exhibited two redox peaks attributed to electroactive transitional state around 0.8 and 0.6. Polyaniline addition to hydrogel decreased the hydrogel swelling capacity because of the hydrophobic nature of polyaniline from 60% to 30%. Cell viability test revealed that the conductive substrate enhanced cellular proliferation. Agarose/polyaniline can be widely utilized in tissue engineering because of adjustable swelling behavior and conductivity, which can affect cellular activity and regeneration.

3D Printing of Polycaprolactone–Polyaniline Electroactive Scaffolds for Bone Tissue Engineering

“…Therefore, it is necessary to characterise the prepared PANI powder using FTIR and XRD to confirm the successful synthesis of PANI in the conductive form. The FTIR spectra of the PANI powder shows several signature peaks of PANI emeraldine salt such as: (i) peaks at 1554 cm −1 and 1477 cm −1 belonging to the stretching vibration of quinoid (Q) and benzenoid (B) rings of PANI respectively, (ii) peak at 1301 cm −1 is correlated with delocalisation of π electrons induced in PANI through protonation, (iii) peak at 1244 cm −1 is attributed to C-N stretch vibration in the polaron structure appearing near the secondary amine structure and also as the ribbon characteristic of the protonated form [27] (Figure 2a). Characteristic of the PANI emeraldine salt is a transmittance that continues to rise above the wavelength of 1600 cm −1 ; this is due to the absorption of the free charge carriers in doped polymers [60].…”

“…However, PANI has limitations such as nonbiodegradability and contradictory evidence within the literature regarding the materials biocompatibility. Numerous studies have stated that the material is cytocompatible [25][26][27][28][29][30][31][32] although it may require specific treatments to improve compatibility; however, cytotoxicity and inflammation have also been reported [22,24,33]. Therefore, it is crucial to identify the cytotoxic concentration limit of PANI within a scaffold and procedures to ensure that residual dopants and low molecular weight by-products are not present as these have been suggested to be responsible for the poor biocompatibility [26,33].…”

“…Typically, PANI is utilised in a polymeric composite to overcome its inherent brittleness after synthesis. Biodegradable and biocompatible polymers such as polycaprolactone (PCL) [34], poly(ethylene glycol) diacrylate [35], poly(lactic acid) [36], poly(d,l-lactide) [37], gelatin [38][39][40][41], and agarose [27] have been utilised to produce constructs for tissue engineering applications. Further difficulties are observed in processing due to its limited solubility in common organic solvents.…”

“…Further difficulties are observed in processing due to its limited solubility in common organic solvents. PANI based electroactive scaffolds have been fabricated using various conventional fabrication routes such as in situ polymerisation/thermal induced separation [42], solution casting [10,26], hydrogel formation [27,35,39,40,42,43], and electrospinning [11,38,[44][45][46]. However, these methods offer limited control of scaffold morphological properties such as pore size, interconnectedness, and fibre diameter.…”

Electrospun electroactive nanofibers of gelatin‐oligoaniline/Poly (vinyl alcohol) templates for architecting of cardiac tissue with on‐demand drug release

“…Oligoaniline‐based biomaterial degradation rate can be tuned in comparison with polyaniline. Aniline oligomers can be used to adjust the scaffold properties such as mechanical feature, hydrophilicity, and degradation rate and drug release . Atoufi et al synthesized alginate‐aniline tetramer scaffold, which exhibited the shape‐memory behavior, adjustable swelling, and degradation rate .…”