Graphene Hybrid Anisotropic Structural Color Film for Cardiomyocytes' Monitoring

Abstract

Heart‐on‐a‐chip based on microfluidic platform can simulate the structure and reveal the function of heart at the micrometer level, compensating the gap between organism and experiments in vitro. In this paper, a novel heart‐on‐a‐chip system integrated with reduced graphene oxide (rGO) hybrid anisotropic structural color film is designed for cardiac sensing and evaluation. This hybrid anisotropic film is based on the opposite adhesion properties of the polyethylene glycol diacrylate (PEGDA) and gelatin methacryloyl (GelMA). The PEGDA area with low adhesion rate has inverse opal structure and specific reflection peak, while microgroove‐patterned rGO‐doped GelMA area with high adhesion rate provides the cardiomyocytes with excellent growing environment and induced orientation property. Benefiting from the design, the cultured cardiomyocytes only adhere in specific area without affecting the surface microstructure of the structural color. When cardiomyocytes recover beating, its elongation and contraction will stretch the structure of PEGDA and result in a color shift, which realizes the transformation from micromechanics to macroscopic optics. In addition, the heart‐on‐a‐chip system based on the anisotropic structural color hydrogels and microfluidics provides an outstanding visible method for cardiac sensing, which is of great significance in cardiac pathophysiological studies and drug detection in vitro.

Oriented Neural Spheroid Formation and Differentiation of Neural Stem Cells Guided by Anisotropic Inverse Opals

“…The topography of these materials influences the mechanosensory apparatus and the spatiotemporal dynamics of the cells ( Chen et al, 2014 ), and these cell-material interactions play a key factor in cell behavior regulation ( Guilak et al, 2009 ; Zangi et al, 2016 ). Many kinds of biomaterials have been investigated for guiding cell growth through topography, including nanofibers ( Liu et al, 2010 ; Xie et al, 2014 ; Omidinia-Anarkoli et al, 2017 ; Zuidema et al, 2018 ; Li et al, 2019 ), colloidal nanoparticles ( Antman-Passig et al, 2017 ; Musoke-Zawedde and Shoichet, 2006 ), and inverse opal materials ( Lu et al, 2014 ; Shang et al, 2019 ; Li et al, 2020 ). Among the applied biomaterials, inverse opal materials represent a class of porous structures with an ordered array of uniform nanoscale or microscale pores, which possessed well-controlled pore size, long-range ordered structure, and homogeneous interconnectivity.…”

Mechanochromism of Structural‐Colored Materials

“…Moreover, with similar strategy, a series of soft‐bodied robots were developed in the shape of guppies and crawling caterpillars. [ 141,142 ] In addition to artificial structural color materials such as opals or inverse opals, [ 140–143 ] natural mechanochromic structures such as butterfly wings have also been used to obtain self‐actuated robots, [ 144 ] demonstrating the tremendous potential of such biohybrid systems.…”

Applications of Gelatin Methacryloyl (GelMA) Hydrogels in Microfluidic Technique-Assisted Tissue Engineering

“…This chip may serve as a potential platform for the fibrosis pathology study. Li et al [95] developed a heart-on-a-chip with hydrogel films to mimic the cardiac structure and function. Reduced graphene oxide (rGO)-doped heterogeneous hydrogel film with GelMA hydrogels and polyethylene glycol diacrylate (PEGDA) was utilized to increase the contrast of the structural color as a dark background and to enhance the beating consistency of cardiomyocytes (the conductive rGO was doped in GelMA hydrogel).…”

“…On this chip, cardiomyocytes were cultured to test the stimulation effect of isoproterenol, propranolol, and verapamil on the cells. Therefore, this platform was considered to be a promising tool for cardiac pathophysiological study and drug screening [95]. Wang et al [96] reported a microfluidic tumor progression model based on metastasis-on-a-chip.…”