Ternary MXene-loaded PLCL/collagen nanofibrous scaffolds that promote spontaneous osteogenic differentiation

Abstract

Conventional bioinert bone grafts often have led to failure in osseointegration due to low bioactivity, thus much effort has been made up to date to find alternatives. Recently, MXene nanoparticles (NPs) have shown prominent results as a rising material by possessing an osteogenic potential to facilitate the bioactivity of bone grafts or scaffolds, which can be attributed to the unique repeating atomic structure of two carbon layers existing between three titanium layers. In this study, we produced MXene NPs-integrated the ternary nanofibrous matrices of poly(L-lactide-co-ε-caprolactone, PLCL) and collagen (Col) decorated with MXene NPs (i.e., PLCL/Col/MXene), as novel scaffolds for bone tissue engineering, via electrospinning to explore the potential benefits for the spontaneous osteogenic differentiation of MC3T3-E1 preosteoblasts. The cultured cells on the physicochemical properties of the nanofibrous PLCL/Col/MXene-based materials revealed favorable interactions with the supportive matrices, highly suitable for the growth and survival of preosteoblasts. Furthermore, the combinatorial ternary material system of the PLCL/Col/MXene nanofibers obviously promoted spontaneous osteodifferentiation with positive cellular responses by providing effective microenvironments for osteogenesis. Therefore, our results suggest that the unprecedented biofunctional advantages of the MXene-integrated PLCL/Col nanofibrous matrices can be expanded to a wide range of strategies for the development of effective scaffolds in bone tissue regeneration. Graphical Abstract

3D bioprinting of human mesenchymal stem cells-laden hydrogels incorporating MXene for spontaneous osteodifferentiation

“…2-hydroxy-4′-(2-hydroxyethoxy)-2-methylpropiophenone (Irgacure 2959, TCI Co., Tokyo, Japan) powder was added to the GelMA/HAMA bioink solution to obtain a final concentration of 0.1% (w/v), respectively. The bioink precursor solution was homogeneously vortexed and maintained in a water bath at 37 °C for 6 h. Ti 3 C 2 T x MXene NPs were prepared by HF etching of Ti 3 AlC 2 MXene powder using the vacuum filtration and drying process, as previously described [ 42 ]. The MXene NPs solution in DI water was prepared by sonicating for 1 h to distribute them evenly throughout the solution and was mixed with the GelMA/HAMA bioink at the final concentration of 50 μg ml −1 .…”

“…MXene NPs are a generic term for transition metal carbide/nitride produced by selective etching of A of the MAX phase, where M represents a transition metal, A represents a group 13 or 14 element, and X represents nitrogen or carbon. Recently, using the excellent properties of MXene NPs, it is used in energy storage, photodynamic therapy, biosensor, drug delivery, and tissue engineering fields [ [38] , [39] , [40] , [41] , [42] ]. Interestingly, due to the unique biocompatibility and bioactivity of MXene NPs, it is known to promote bone formation and improve osseointegration and osteoconductivity [ [42] , [43] , [44] ].…”

“…Recently, using the excellent properties of MXene NPs, it is used in energy storage, photodynamic therapy, biosensor, drug delivery, and tissue engineering fields [ [38] , [39] , [40] , [41] , [42] ]. Interestingly, due to the unique biocompatibility and bioactivity of MXene NPs, it is known to promote bone formation and improve osseointegration and osteoconductivity [ [42] , [43] , [44] ]. Additionally, recent research reported that the incorporation of MXene NPs in hydrogels increases mechanical strength [ [45] , [46] , [47] ].…”

Biosafety of inorganic nanomaterials for theranostic applications

“…After cell membrane damage, LDH releases outside of the cell and oxidizes lactate to generate nicotinamide adenine dinucleotide-H (NADH), then reacts with WST to generate a yellow color. Using a microplate reader, the intensity of yellow dye correlates directly with the number of cells with damaged membranes [55].…”

“…Overall, cytotoxicity of MXene nanosheets was observed for cells of cancer origin suggesting their cell-dependent working mechanisms. Lee et al assessed the cytotoxicity of Single-or few-layered Ti 3 AlC 2 MXene nanosheets on MC3T3-E1 cells [55]. Using the CCK-8 assay, there was no significant cytotoxicity under 125 µg/ml MXene treatment; however, time-and dosedependent cytotoxicities were observed at 250 µg/ml after 24 h and 62.5-250 µg/ml after 48 h. This cytotoxicity is suggested to be derived from serious membrane damages at 250 µg/mL, which was assessed from LDH release assay and microscopic observation.…”