Tunable Thiol–Ene Photo-Cross-Linked Chitosan-Based Hydrogels for Biomedical Applications

Abstract

Access to biocompatible hydrogels with tuneable properties is of great interest in biomedical applications. Here we report the synthesis and characterisation of a series of photocrosslinked chitosan hydrogels from norbornene-functionalised chitosan (CS-nb) and various thiolated crosslinkers. The resulting materials were characterised by NMR, swelling ratio, rheology, SEM and small angle neutron scattering (SANS) measurements. The hydrogels exhibited pH-and salt-dependent swelling, whilst the macro-and micro-scale properties could be modulated by the choice and degree of crosslinker or the polymer concentration. The materials could be moulded in situ and loaded with small molecules that can be released overtime. Moreover, the incorporation of collagen in the hydrogels drastically improved cell adhesion, with excellent viabilities of human dermofibroblast cells on the hydrogels observed for up to 6 days, highlighting the potential use of these materials in the biomedical area.

Photocrosslinkable natural polymers in tissue engineering

“…As for chitosan, the norbornene moiety is acquired by amide bond formation, which is initiated by the reaction between chitosan and carbic anhydride [norbornene-derived chitosan (CS-nbn-COOH)] (Michel et al, 2019(Michel et al, , 2020. In one research, thiolated diethylene glycol (HS-DEG-SH) was used as a crosslinker and Irgacure 2959 was utilized as a photoinitiator [UV-A (320-400 nm)] (Michel et al, 2019).…”

The Low-Waste Grafting Copolymerization Modification of Chitosan Is a Promising Approach to Obtaining Materials for Food Applications

“…The large volume of research and practical interest in chitin and chitosan are driven by their unique structures, which, due to the presence of both hydroxyl and amine groups, lead to a variety of functional features. Moreover, Cht is characterized as a biocompatible, low-toxic, biodegradable polymer possessing a high sorption capacity for a multitude of compounds [ 1 , 2 , 3 , 4 , 5 ].…”

Multifaceted Shape Memory Polymer Technology for Biomedical Application: Combining Self-Softening and Stretchability Properties

“…The thiol-ene reaction, described in later sections, is a photochemically induced radical step-growth polymerization reaction. Thiol-ene photo crosslinked reactions have been employed in various applications like wound healing, drug delivery, and tissue engineering, as well as in microfluidic applications [2][3][4]. Moreover, the thiol-ene/acrylate polymer system based on TATATO, TMTMTP, and Tricyclodecane dimethanol diacrylate (TCMDA) has displayed a thermally induced shape memory effect, softening property, and biocompatibility [5,6].…”