3D Printed Chitosan Composite Scaffold for Chondrocytes Differentiation
Authors: Sahai Nitin , Gogoi Manashjit , Tewari Ravi Prakash 
Published: December 2020

Aims:
Our aim is to develop 3D printed chitosan-gelatin-alginate scaffolds using a costeffective
in house designed 3D printer followed by its characterization. To observe chondrocyte differentiation
on 3D printed scaffolds as part of scaffold application.

Background:
Cartilage is considered to be a significant tissue in humans. It is present in between
the rib cage, the lobe of the ear, nasal septum in the form of hyaline cartilage, in between ribs costal
cartilage, intervertebral discs in the form of fibrocartilage, meniscus, larynx, epiglottis and between
various joints of bones. To replace or repair damaged tissues due to disorders or trauma,
thousands of surgical procedures are performed daily. 3D printing plays a crucial role in the development
of controlled porous architectures of scaffolds for cartilage tissue regeneration. Advancement
in 3D printing technology like inkjet, micro- extrusion in 3D bioprinting, Laser-assisted 3D
Bioprinting (LAB), stereolithography combination with biomaterials plays a crucial role in the
quick development of patient-specific articulating cartilage when need in a short period frame.

Objective:
Our objective is to develop different compositions of chitosan-gelatin-alginate composite
hydrogel scaffolds with controlled porosity and architectures with the application of 3D
printing and observe the growth of cartilage on it. To achieve as proposed, an in-house 3D paste extruder
printer was developed, which is capable of printing porous composite chitosan hydrogel scaffolds
of desired architecture layer by layer. After the characterization of 3D printed chitosan composite
scaffolds, the differentiation of chondrocyte was observed using hMSC.

Methods:
In present paper process for the development of chitosan-alginate-gelatin composite hydrogel,
3D printing, morphological characterization, and observation for differentiation of chondrocytes
cells on 3D printed chitosan composite hydrogels is presented. The present study is divided
into three parts: in first part development of composite chitosan-alginate-gelatin hydrogel with the
utilization of in house customized assembled paste extruder based 3D printer, which is capable of
printing chitosan composite hydrogels. In the second part, the characterization of 3D printed chitosan
composite scaffolds hydrogel is performed for evaluating the morphological, mechanical,
and physical properties. The prepared composite scaffolds were characterized by Fourier Transform
Infrared Spectroscopy (FTIR), X-Ray Diffraction(XRD), Scanning Electron Microscopy
SEM, swelling property, mechanical testing, porosity, etc. In the last part of the study, the differentiation
of chondrocytes cells was observed with human Mesenchymal Stem Cells (hMSC) on 3D
printed scaffolds and showed positive results for the same.

Results:
Stereolithography (STL) files of 3D models for porous chitosan composite were developed
using Computer-Aided Design (CAD) and printed with a hydrogel flow rate within the range
of 0.2-0.25 ml/min. The prepared scaffolds are highly porous, having optimum porosity, optimal
mechanical strength to sustain the cartilage formation. The 3D printed chitosan composite scaffolds
show supports for the differentiation of chondrocytes. The above study is helpful for in-vivo
regeneration of cartilage for patients having related cartilage disorders.

Conclusion:
This method helps in regeneration of degenerated cartilage for patient-specific and
form above experiment we also concluded that 3D printed chitosan scaffold is best suited for the regeneration
of chondrocyte cells.