Evaluation of poly(L-lactide) and chitosan composite scaffolds for cartilage tissue regeneration

Abstract

The present study delineates the development of chitosan and poly(L-lactide) (PLLA) scaffolds cross-linked using a mixture of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), n-hydroxysuccinimide (NHS), and chondroitin sulfate (CS) for cartilage tissue engineering applications. Chitosan and PLLA were varied in concentration for developing scaffolds and prepared by freeze-drying method. The various scaffolds were studied using scanning electron microscopy (SEM), porosity by mercury intrusion porosimeter, and the molecular interactions among polymers using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) studies. Differential scanning calorimetry (DSC) was used to predict the thermal properties of the scaffolds. The mechanical properties of the scaffolds were studied using static mechanical tester. The ability of the scaffolds to support chondrocyte proliferation was also studied. The microscopy suggests that the pore size of the scaffolds varied with the composition in the range of 38-172 μm and the porosities in the range of 73-93%. The XRD and the FTIR studies suggested that an alternation in the composition of the scaffolds altered the molecular interactions among the scaffold components. An increase in the chitosan content enhanced the swelling property. The degradation of the scaffolds was least when the proportion of chitosan and PLLA was in the ratio of 70:30. The in vitro cell proliferation study suggested that the developed scaffolds were able to support chondrogenesis, the glycosaminoglycan (GAG) content of the mature chondrocyte was 40 μg/ml and the viability was approximately 90%. Hence, the so designed scaffolds may be tried for cartilage tissue engineering applications.

Poly-l-Lactic Acid (PLLA)-Based Biomaterials for Regenerative Medicine: A Review on Processing and Applications

“…Natural polymers have been widely used in blends with synthetic polymers since their ECM-like structure enhances the cell growth and adhesion on the hybrid construct. There are several lines of research for tissue engineering applications aiming to fabricate hybrid scaffolds from PLLA and natural polymers, such as collagen [ 22 ], chitosan [ 51 , 113 ], silk fibroin [ 66 , 109 ], and gelatin [ 107 , 138 ].…”

“…The authors tested the influence of the internal architecture of the porous 3D printed scaffolds on their mechanical properties, resulting in a maximum tensile strength of 18 MPa, in line with the range of 0.8–25 MPa that commonly occurs for cartilage tissue [ 171 ]. The mechanical properties of PLLA-based, sponge-like scaffolds for cartilage TE were also investigated by Mallick et al [ 113 ]. They fabricated hybrid chitosan/PLLA scaffolds at different concentrations by means of the freeze-drying method.…”

“… Structure of PLLA-based scaffold designed for bone, cartilage, blood vessel, and skin regeneration. Reprinted with permission from Elsevier [ 82 ], Taylor & Francis [ 113 ], Dovepress [ 161 ], and RSC [ 162 ]. …”

Recent Progress on Biodegradable Tissue Engineering Scaffolds Prepared by Thermally-Induced Phase Separation (TIPS)

“…For instance, blending with CS is considered as an efficient approach to obviate some of the indicated drawbacks [ 193 ]. Such blending permits taking advantages of both polymers not only as scaffolds for bone [ 194 ], cartilage [ 195 ] and nerve [ 196 ] tissue engineering applications, but also as drug delivery carriers [ 197 ].…”