Preparation and In Vitro Evaluation of Chitosan-g-Oligolactide Based Films and Macroporous Hydrogels for Tissue...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Polymer Chemistry

Background:

• Chitosan-based materials are widely explored for biomedical applications due to their biocompatibility and biodegradability.
• Developing novel copolymer matrices can enhance material properties for specific tissue engineering needs.
• Understanding the influence of copolymer composition on degradation and cellular response is crucial for optimizing biomaterial design.

Purpose of the Study:

• To fabricate and characterize novel chitosan-g-oligo (L,L-lactide) (Chit-LL) and chitosan-g-oligo (L,D-lactide) (Chit-LD) copolymer matrices in film and 3D hydrogel forms.
• To evaluate the in vitro degradation behavior of the developed copolymer matrices.
• To assess the cytocompatibility, cell proliferation, and osteogenic differentiation potential of mesenchymal stromal cells (MSCs) within these matrices.

Main Methods:

• Solid-state mechanochemical synthesis was employed to create chitosan-lactide copolymers.
• Solvent casting and lyophilization techniques were used to prepare 2D films and 3D macroporous hydrogels, respectively.
• In vitro degradation, cell culture (L929 fibroblasts and MSCs), confocal laser scanning microscopy (CLSM), and quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) were utilized for characterization and biological evaluation.

Main Results:

• The 3D hydrogels exhibited a macroporous structure with interconnected pores (average size ~150 μm).
• Chit-LL hydrogels showed increased degradation (34%), while Chit-LD hydrogels exhibited decreased degradation (23%) compared to chitosan.
• Both Chit-LL and Chit-LD matrices supported cell adhesion, proliferation, and swelling, with Chit-LD films demonstrating maximal osteogenic differentiation markers (ALPL, Runx2, SPP1).

Conclusions:

• Chitosan-g-oligo (L,L-lactide) and (L,D-lactide) copolymer matrices are successfully fabricated and exhibit tunable degradation properties.
• These novel matrices demonstrate excellent biocompatibility, supporting cell growth and proliferation.
• The findings indicate that Chit-LD copolymer films are particularly promising for promoting osteogenic differentiation, highlighting their potential for bone tissue engineering applications.