Pectin as Rheology Modifier of a Gelatin-Based Biomaterial Ink

Abstract

Gelatin is a natural biopolymer extensively used for tissue engineering applications due to its similarities to the native extracellular matrix. However, the rheological properties of gelatin formulations are not ideal for extrusion-based bioprinting. In this work, we present an approach to improve gelatin bioprinting performances by using pectin as a rheology modifier of gelatin and (3-glycidyloxypropyl)trimethoxysilane (GPTMS) as a gelatin–pectin crosslinking agent. The preparation of gelatin–pectin formulations is initially optimized to obtain homogenous gelatin–pectin gels. Since the use of GPTMS requires a drying step to induce the completion of the crosslinking reaction, microporous gelatin–pectin–GPTMS sponges are produced through freeze-drying, and the intrinsic properties of gelatin–pectin–GPTMS networks (e.g., porosity, pore size, degree of swelling, compressive modulus, and cell adhesion) are investigated. Subsequently, rheological investigations together with bioprinting assessments demonstrate the key role of pectin in increasing the viscosity and the yield stress of low viscous gelatin solutions. Water stable, three-dimensional, and self-supporting gelatin–pectin–GPTMS scaffolds with interconnected micro- and macroporosity are successfully obtained by combining extrusion-based bioprinting and freeze-drying. The proposed biofabrication approach does not require any additional temperature controller to further modulate the rheological properties of gelatin solutions and it could furthermore be extended to improve the bioprintability of other biopolymers.

Pectin-Based Scaffolds for Tissue Engineering Applications

“…Cells were successfully loaded within this formulation and 3D bioprinted to produce living 3D constructs [24]. From that moment, other pectin-based inks have been developed and optimized to produce 3D scaffolds with high shape fidelity [49][50][51]. For example, pectin-based scaffolds with more complex shapes such as a human ear and nose shape for cartilage tissue regeneration were successfully obtained (Figure 6) [41].…”

Biomaterials for Regenerative Medicine in Italy: Brief State of the Art of the Principal Research Centers

“…Secondly, the Research Center “E. Piaggio” and 3R Center (Department of Civil and Industrial Engineering) of Pisa University work on ameliorating biomimetic patches for myocardial repair, which is used for providing a 3D structural support for cellular growth during new tissue formation ( Figure 4 ) [ 119 , 120 ]. In addition, they developed novel peptide-modified scaffolds as biomimetic matrices; these scaffolds mimic the biomolecular signals of the ECM, improving cardiac progenitor cell adhesion and differentiation toward myocardial phenotypes [ 121 ].…”

“… Materials Characteristics Applications Ref. dECM 3D structure Heterogeneity Mechanical support Suitable microenvironment Regeneration of skeletal muscle tissue Stimulation of myogenesis and angiogenesis Scaffold Restoration of damaged organs [ 103 , 104 , 105 , 106 , 110 , 111 , 112 ] Gelatin Structural support Cardio-inductivity Slow biodegradation rate Rheological properties Biomimetic cardiac patch Drug delivery Tissue engineering of skeletal muscle [ 118 , 120 ] PLGA Adaptable structure Drug delivery systems Bioartificial 3D cardiac patch Suitable for cardiovascular cell growth [ 117 , 118 ] Silk fibroin Biocompatibility Textile layers Cellular adhesiveness Low immunogenicity Development of vascular grafts/tubular scaffolds Promotion of vascularization Repair of skin wound [ 115 , 116 ] …”

“…( B.3 , C.2 , D.2 , E.2 ) Pictures of 3D woodpile structures as bioprinted and ( D.3 , D.4 , E.3 , E.4 ) as freeze-dried (scale bars = 5 mm). Reproduced with permission [ 120 ].…”

Valorization of a Levulinic Acid Platform through Electrospinning of Polyhydroxyalkanoate-Based Fibrous Membranes for In Vitro Modeling of Biological Barriers

“…The valorization of industrial by-products to produce polymers or additives , and green solvents , extracted from biomasses can potentially reduce the dependency from non-renewable resources. The identification of fabrication technologies able to process together these biopolymers and green solvents into added-value products offers a valuable approach to further boost their large-scale production and therefore their cost-effective introduction in everyday life. − …”