Preliminary Evaluation of 3D Printed Chitosan/Pectin Constructs for Biomedical Applications

Abstract

In the present study, chitosan (CS) and pectin (PEC) were utilized for the preparation of 3D printable inks through pneumatic extrusion for biomedical applications. CS is a polysaccharide with beneficial properties; however, its printing behavior is not satisfying, rendering the addition of a thickening agent necessary, i.e., PEC. The influence of PEC in the prepared inks was assessed through rheological measurements, altering the viscosity of the inks to be suitable for 3D printing. 3D printing conditions were optimized and the effect of different drying procedures, along with the presence or absence of a gelating agent on the CS-PEC printed scaffolds were assessed. The mean pore size along with the average filament diameter were measured through SEM micrographs. Interactions among the characteristic groups of the two polymers were evident through FTIR spectra. Swelling and hydrolysis measurements confirmed the influence of gelation and drying procedure on the subsequent behavior of the scaffolds. Ascribed to the beneficial pore size and swelling behavior, fibroblasts were able to survive upon exposure to the ungelated scaffolds.

Chitosan‐based nanocomposites for medical applications

“…Many features such as cytotoxicity, mechanical properties as well as healing efficiencies have to be considered while fabricating a scaffold/substrate for tissue regeneration. Various existing methodologies have been adapted for processing of chitosan‐based nanocomposites into films, 34 fiber‐meshes, 35 hydrogels, 36–40 and 3D printed constructs 41 to mimic the 3D environment of tissues. Processing into a freestanding thin film is the easiest choice and affordable route to evaluate the physico‐mechanical properties and biocompatibility of the designed nanocomposites 42–44 .…”

Preparation and Characterization of Salt-Mediated Injectable Thermosensitive Chitosan/Pectin Hydrogels for Cell Embedding and Culturing

“…The three hydrogels reached very fast (less than 30 min) and very high swelling values (between 1500 and 2000%) in both formulations with and without DMEM, faster and higher values than similar Ch-Pe systems proposed by other authors that reported lower swelling ratio values (about 370% [ 27 ], 150–200% [ 40 ] or slower [ 15 ]) [ 14 , 29 , 31 , 41 ]. Regarding the in vitro stability, tested up to 25 days, hydrogels without DMEM were stable up to 25 days, except for the Ch-Pec-PB samples that completely degraded after 7 days.…”

“…In this study, we aimed at developing a chitosan/pectin hydrogel system suitable for cell embedding and culturing, meeting, therefore, some fundamental chemico-physical requirements, such as (i) a physiological pH, (ii) injectability at r.t. and (iii) ability to gel at the physiological temperature, i.e., 37 °C. Several hydrogels with chitosan and pectin have been proposed in the literature; however, they are usually in the gel state at r.t. and in the sol state at high temperatures used to solubilize the two polymers (60 to 97 °C), conditions not suitable for cell viability [ 14 , 15 , 16 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. To overcome the limits of the chitosan/pectin systems reported in the literature, not compatible with cell embedding applications, in the present study, we decided to exploit the well-known ability of chitosan solution to gel at 37 °C thanks to the addition of weak bases such as βGP, in order to induce the formation of a chitosan hydrogel network that incorporates pectin inside, giving rise to a semi-IPN.…”

“…In order to improve the performance of single-polymer hydrogels, hybrid hydrogels, composed of two different polymers, can be developed that present more controlled physicochemical properties [ 13 ]. Among hybrid hydrogels made of natural polymers, chitosan/pectin systems have recently been proposed for tissue engineering applications and drug delivery systems [ 14 , 15 ]. Chitosan, a deacetylated derivative of chitin, is a cationic polysaccharide, localized in the exoskeleton of crustaceans [ 16 ].…”

Polysaccharide 3D Printing for Drug Delivery Applications

“…Similarly to sodium alginate, due to its carboxylic groups, pectin forms polyelectrolyte complexes with CS. Michailidou et al assessed the printability of CS/Pec hydrogels [133]. The addition of Pec increased significantly the viscosity of the CS/Pec hydrogels and consequently improved the shape fidelity of the printed constructs.…”