2017/06/09 by Róisín Holmes, Holmes, Roisin, Xuebin Yang +10 · 1 citation
Engineering · Materials Science · Medicine · #3D Printing in Biomedical Research #Chemical Physics (physics.chem-ph) #Collagen: Extraction and Characterization #FOS: Physical sciences #Osteoarthritis Treatment and Mechanisms #Silk-based biomaterials and applications
paper · pdf · doi:10.48550/arxiv.1706.03043
openalex publication_date 2017/06/09 · openalex created_date 2022/10/01 · openalex updated_date 2026/07/28
Thiol-ene photo-click hydrogels were prepared via step-growth polymerisation\nusing thiol-functionalised type-I collagen and 8-arm poly(ethylene glycol)\nnorbornene terminated (PEG-NB), as a potential injectable regenerative device.\nType-I collagen was thiol-functionalised by a ring opening reaction with\n2-iminothiolane (2IT), whereby up to 80 Abs% functionalisation and 90 RPN%\ntriple helical preservation were recorded via 2,4,6-Trinitrobenzenesulfonic\nacid (TNBS) colorimetric assay and circular dichroism (CD). Type, i.e.\n2-Hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone (I2959) or lithium\nphenyl-2,4,6-trimethylbenzoylphosphinate (LAP), and concentration of\nphotoinitiator were varied to ensure minimal photoinitiator-induced\ncytotoxicity and to enable thiol-ene network formation of collagen-PEG\nmixtures. The viability of G292 cells following 24 h culture in\nphotoinitiator-supplemented media was largely affected by the photoinitiator\nconcentration, with I2959-supplemented media observed to induce higher toxic\nresponse compared to LAP-supplemented media. In line with the in vitro study,\nselected photoinitiator concentrations were used to prepare thiol-ene\nphoto-click hydrogels. Gelation kinetics proved to be largely affected by the\nspecific photoinitiator, with LAP-containing thiol-ene mixtures leading to\nsignificantly reduced complete gelation time with respect to I2959-containing\nmixtures. Other than the specific photoinitiator, the photoinitiator\nconcentration was key to adjust hydrogel storage modulus (G'), whereby 15-fold\nG' increase was observed in samples prepared with 0.5% (w/v) compared to 0.1%\n(w/v) LAP. The photoinitiator-gelation-cytotoxicity relationships established\nin this study will be instrumental to the design of orthogonal collagen-based\nniches for regenerative medicine.\n