Emerging Trends in Nanocarbon‐Based Cardiovascular Applications

The era of nano-bionic: 2D materials for wearable and implantable body sensors

Nano-bionics have the potential of revolutionizing modern medicine. Among nano-bionic devices, body sensors allow to monitor in real-time the health of patients, to achieve personalized medicine, and even to restore or enhance human functions. The advent of two-dimensional (2D) materials is facilitating the manufacturing of miniaturized and ultrathin bioelectronics, that can be easily integrated in the human body. Their unique electronic properties allow to efficiently transduce physical and chemical stimuli into electric current. Their flexibility and nanometric thickness facilitate the adaption and adhesion to human body. The low opacity permits to obtain transparent devices. The good cellular adhesion and reduced cytotoxicity are advantageous for the integration of the devices in vivo. Herein we review the latest and more significant examples of 2D material-based sensors for health monitoring, describing their architectures, sensing mechanisms, advantages and, as well, the challenges and drawbacks that hampers their translation into commercial clinical devices.

Parametric Optimization of 3D Printed Hydrogel-Based Cardiovascular Stent

PURPOSE

This study aimed to develop personalized biodegradable stent (BDS) for the treatment of coronary heart disease. Three-dimensional (3D) printing technique has offered easy and fast fabrication of BDS with enhanced reproducibility and efficacy.

METHODS

A variety of BDS were printed with 3 types of hydrogel (~5 ml) resources (10%w/v sodium alginate (SA), 10%w/v cysteine-sodium alginate (SA-CYS), and 10%w/v cysteine-sodium alginate with 0.4%w/v PLA-nanofibers (SA-CYS-NF)) dispersed from an 22G print head nozzle attached to the BD-syringe. The printability of hydrogels into 3D structures was examined based on such variables as hydrogel's viscosity, printing distance, printing speed and the nozzle size.

RESULTS

It was demonstrated that alginate composition (10%w/v) offered BDS with sufficient viscosity that defined the thickness and swelling ratio of the stent struts. The thickness of the strut was found to be 338.7 ± 29.3 μm, 262.5 ± 14.7 μm and 237.1 ± 14.7 μm for stents made of SA, SA-CYS and SA-CYS-NF, respectively. SA-CYS-NF stent displayed the highest swelling ratio of 38.8 ± 2.9% at the initial 30 min, whereas stents made of SA and SA-CYS had 23.1 ± 2.4% and 22.0 ± 2.4%, respectively.

CONCLUSION

The printed stents had sufficient mechanical strength and were stable against pseudo-physiological wall shear stress. An addition of nanofibers to alginate hydrogel significantly enhanced the biodegradation rates of the stents. In vitro cell culture studies revealed that stents had no cytotoxic effects on human umbilical vein endothelial cells (HUVECs) and Raw 264.7 cells (i.e., Monocyte/macrophage-like cells), supporting that stents are biocompatible and can be explored for future clinical applications.