Combination of 3D printing and electrospinning to develop chitin/gelatin/PVA scaffolds

Abstract

In this study, novel scaffolds based on natural polymers were developed by combining 3D printing (3DP) and electrospinning (ES) techniques. ES ink was prepared with gelatin and poly(vinyl alcohol) (PVA), while 3DP ink was prepared with gelatin and chitin. Different biopolymers were used to confer unique properties to each ink and obtain a multilayered scaffold suitable for tissue regeneration. First, gelatin is able to exhibit the characteristics needed for both inks since gelatin chains contain arginine-glycine-aspartic (RGD) motifs, an important sequence in the promotion of cell adhesion, which gives gelatin an improved biological behavior in comparison to other polymers. Additionally, PVA was selected for ES ink to facilitate gelatin spinnability, and chitin was incorporated into 3DP ink as reinforcement to provide mechanical support and protection to the overall design. In this work, chitin was extracted from fruit fly pupae. The high extraction yield and purity of the chitin obtained from the fruit fly pupae confirmed that this pupa is an alternative source to produce chitin. Once the chitin was characterized, both inks were prepared and rheological analysis was carried out in order to confirm the shear thinning behavior required for additive manufacturing processes. The combination of 3DP and ES processes resulted in porous scaffolds, which were proven biocompatible, highlighting their potential for biomedical applications.

Electrospun Chitosan-Based Nanofibrous Coating for the Local and Sustained Release of Vancomycin

“…While viscosity is commonly regarded as the primary rheological parameter to be evaluated, in our specific process, the viscoelasticity of the fluids plays a pivotal role, as highlighted, for instance, in Castellano et al , For this reason, a comprehensive rheological characterization, particularly in the LVER, is needed and is best accomplished through amplitude sweep and frequency sweep tests. , In particular, the LVER can be determined only after performing amplitude sweep measurements, applying different shear strains on the polymeric solutions, and evaluating their response. , On the other hand, frequency sweep tests are necessary for describing the viscoelastic properties of the different formulations in the oscillatory domain. These tests involve the application of a fixed strain within the previously determined LVER, obtained from the amplitude sweep tests.…”

“… 80 , 81 In particular, the LVER can be determined only after performing amplitude sweep measurements, applying different shear strains on the polymeric solutions, and evaluating their response. 82 , 83 On the other hand, frequency sweep tests are necessary for describing the viscoelastic properties of the different formulations in the oscillatory domain. These tests involve the application of a fixed strain within the previously determined LVER, obtained from the amplitude sweep tests.…”

Optimization of Ink Composition and 3D Printing Process to Develop Soy Protein-Based Scaffolds

“…Based on these findings, the ink formulation containing 25 wt% PVA was selected for further investigation, specifically to evaluate the impact of temperature and the addition of SA or GEL. (20,25, and 30 wt%) before (A) and after heat treatment (D). Viscosity curves of SPI25PVA ink with different contents of SA (1, 2, and 3 wt%) before (B) and after heat treatment (E).…”

“…The overlap was especially good for systems with gelatin, either before or after heating (Figure 2C,F, respectively). Concerning systems with just PVA or with SA, the (20,25, and 30 wt%) before (A) and after heat treatment (D). Viscosity curves of SPI25PVA ink with different contents of SA (1, 2, and 3 wt%) before (B) and after heat treatment (E).…”

“…Regarding gelatin, it is a protein obtained from the hydrolysis of collagen, a structural fibrous protein of the extracellular matrix in animal tissues [24]. Gelatin, unlike collagen, is water-soluble and can be used for the preparation of 3D printing inks [25].…”