Biocompatibility and Nanotoxicity of Layered Two‐Dimensional Nanomaterials

Abstract

Layered two‐dimensional (2D) nanomaterials, such as graphene, transition metal dichalcogenides (TMDs), layered metal oxides (LMOs), black phosphorus (BP), and hexagonal boron nitride (hBN), have attracted tremendous interest recently owing to their unique structural morphologies and outstanding physicochemical properties. Consequently, these nanomaterials have been actively explored for different biological and biomedical applications, such as tissue engineering, drug delivery, bioimaging, and biosensing. As increasing efforts have been focused on identifying the potential bioapplications of layered 2D nanomaterials, one of the fundamental aspects that is of considerable interest and ought to be studied in greater depth is their biocompatibility and nanotoxicity. In addition, as the elucidation and understanding of the physicochemical properties of this new class of nanomaterials are still in their infancy, information on both in vitro and in vivo biocompatibility and nanotoxicity is still scarce and remains poorly understood. As such, there is an immediate need to explore and establish the biocompatibility and nanotoxicological profiles of these nanomaterials in order to develop and optimize them for specific bioapplications. Here, in this Focus Review, we will provide a broad overview of recent advances on the biocompatibility and nanotoxicity of layered 2D nanomaterials. First, a wide range of established and emerging layered 2D nanomaterials actively investigated for bioapplications will be introduced. Next, the different physicochemical aspects governing the biocompatibility and nanotoxicity of these nanomaterials, such as lateral size, concentration, exposure time, number of layers, and chemical composition and surface functionalization, will be evaluated. Finally, we will summarize the review and provide our perspectives on the challenges and opportunities facing this important field.

Assessing and Mitigating the Hazard Potential of Two-Dimensional Materials

“…To date, cytotoxicity of emerging 2D materials has focused mainly on biomedical exposure due to the obvious implications for biomedical technologies. 137,181,182 However, because 2D materials are being explored for a wide range of applications and industries, occupational and environmental exposure also merit investigation. Understanding the effects of all potential exposure routes will provide the most comprehensive picture of the hazard potential associated with 2D materials.…”

Understanding the hemotoxicity of graphene nanomaterials through their interactions with blood proteins and cells

“…34,35 In fact, the nanotoxicity of graphene nanomaterials has been increasingly assessed in recent years. [25][26][27][28][29][30][31][32][33] For example, the in vitro evaluations of the potential cytotoxic effects of graphene nanomaterials have been actively conducted on different human cell lines, 25,[36][37][38][39][40][41] investigations have attributed the cytotoxicity of both graphene and its oxygenated derivative GO on mammalian cells and bacteria to cellular membrane penetration, followed by phospholipid molecule extraction from the lipid bilayer.…”

“…While graphene nanomaterials stand out among the wide array of 2D nanomaterials 35,[44][45][46] and have been regarded as highly attractive for a plethora of biomedical applications, the fundamental mechanisms driving the graphene-protein associations and the physiological effects of graphene nanomaterials on proteins, particularly on their conformational stability as well as physiological activities, are still poorly understood. A comprehensive understanding of these aspects is thus essential for identifying the undesirable adverse effects of FIG.…”

Printing of Soft Stretch Sensor from Carbon Black Composites

“…The use of traditional metallic and semiconducting techniques have been previously demonstrated [1,2], but has limited potential due to the amount of strain that the device can undergo before yielding, which in some areas might be well beyond the traditional strain sensor's capabilities. Most strain sensors operate based on some change in electrical parameters such as capacitance or resistance [3,4]. Piezoresistive sensors can be fabricated as a thin size, single layer using simpler external electronics than capacitive sensors.…”