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Continuous monitoring of implanted vascular implants poses challenges due to the inherent toxicity and instability of contrast agents within the body. The use of biocompatible materials with radiopaque properties offers a solution for continuous monitoring of implanted artificial grafts together with early detection of vascular prosthesis dysfunction, which mitigates the risk of catastrophic failures from leakages or aneurysms. Here, we aimed to develop an artificial vascular graft with enhanced radiopacity to facilitate postsurgery monitoring. To achieve this goal, MXene (Ti3C2 nanosheets) was incorporated into poly-(methyl methacrylate) (PMMA)/polydimethylsiloxane (PDMS) nanofibers via an electrospinning technique, to enhance radiopacity without compromising biocompatibility. The integration of MXene into the nanofiber resulted in an increase in the hydrophilicity of the samples, leading to enhanced cell attachment. Microcomputed tomography imaging was used to verify the radiopacity properties of the samples, showing excellent contrast characteristics. The biocompatibility and hemocompatibility of the samples showed that 50 wt % MXene is the optimal concentration, demonstrating no cytotoxic effects. This is due to the encapsulation of MXene inside the PMMA/PDMS nanofibers preventing the interaction of MXene nanosheets with the physiological environment in vitro while maintaining their radiopacity. This approach herein holds promise as a platform for the long-term monitoring of implanted polymeric materials, thereby addressing a critical unmet need in the field. [ABSTRACT FROM AUTHOR]

The introduction of nanomaterials (NMs) to a fibrous substrate has expanded the spectrum of its applications to various fields of life such as construction, medicine, protection, and energy. These promising outcomes are driving scientists to further explore this area from various aspects, including the introduction of different classes of NMs, their application through numerous approaches, and the potential achievement of various properties. A diamond nanoparticle is a biocompatible material with extraordinary thermal, mechanical, chemical, and optical properties. Nanodiamond (ND) has been extensively studied for its composites with polymers, fabrication, properties, and applications. It was attempted to combine ND with fibrous materials in nanofiber, fiber, filaments, yarns, and fabric, which opened up a new potential application area of ND in textiles. The fabrication, surface characterization, properties, and application of ND with various forms of fibrous materials are outlined in this review, which could be useful for paving the way for researchers to take some advanced steps in this respect. [ABSTRACT FROM AUTHOR]

Compliance mismatch of commercially available artificial grafts, where the artificial graft and the native vessel are subject to different radial expansions, is a major issue that results in graft occlusion after implantation. A human artery possesses a nonlinear mechanical response to pulsatile pressure due to its nonlinear viscoelastic nature, which is difficult to replicate in artificial graft fabrication. Here, we fabricated nanocomposites with nonlinear mechanical responses for potential application as the load-bearing layer of vascular grafts, based on a poly(dimethylsiloxane) (PDMS)-casted nanofibrous film. The nanofibers consisted of a core-sheath structure with a PDMS elastomer reinforced with poly(methyl methacrylate) (PMMA) nanofibers as the sheath and thermoplastic polyurethane (TPU) elastomer as the core. The surface morphology and chemical composition together with the crystalline structure of the nanocomposites were characterized, and dynamic mechanical analysis was performed to select the graft with the most suitable properties as the load-bearing layer of a small-diameter vascular graft. The presence of the stiff polymer PMMA and elastic polymer TPU in the PMMA/PDMS/TPU combination resulted in a delayed dissipation of energy after exposure to a force corresponding to 180 mm Hg. Casting the PDMS/PMMA/TPU nanofibrous mat into a nanocomposite film improved the ultimate tensile strength of PDMS without compromising its elasticity. The compliance values of the nanocomposites were also found to be a close match to those of the greater saphenous vein, demonstrating a great potential of the nanocomposites as the load-bearing layer in a biostable vascular graft.

Nanodiamonds (ND) have been gaining impetus in fields such as medicine and electronics. ND has been widely used to modify polymer surfaces and composites for improved functionality. However, there have been limited research on ND application in regard to textile substrates. In this study, we presented a sustainable coating method, adapted to functionalized ND particles that would be coated onto wool fabric surfaces to enhance hydrophilicity. The application of an ND coating was found to increase wool hydrophilicity because of the presence of additional polar groups, shown by Fourier transform infrared spectrometry, which increased surface energy and fiber roughness. Scanning electron microscopy images revealed that the polar ND-coated wool scales demonstrated improved fiber hydrophilicity. Water absorbency, wicking, and contact angle results for coated fabrics confirmed significant improvement in hydrophilicity, which was directly related to the concentration of ND particles. The optimal concentration of ND was therefore selected to coat the wool fabric. Furthermore, tensile strength and abrasion resistance of the coated fabrics were increased due to the exceptional mechanical properties of ND.