Page 10 - MSAM-2-2

Materials Science in Additive Manufacturing Union of 2D nanomaterials and 3D printing

by the reaction of sodium silicate and aluminum sulfate Transition metal dichalcogenides (TMDs) are another
in an aqueous solution . The resulting solution is then class of 2D materials that consist of transition metal atoms
[52]
neutralized to a pH of around 9, which causes the Laponite (such as molybdenum or tungsten) sandwiched between
particles to form and stabilize . Laponite has a wide chalcogen atoms (such as sulfur or selenium). Due to their
[50]
range of applications in various industries. One of its layer-dependent band structures, TMDs exhibit interesting
most common uses is as a rheology modifier in cosmetics, electronic, optical, and catalytic properties. They have
personal care products, and paints [53-55] . It can also be potential applications in electronics, optoelectronics, and
used as a thickening agent in food products and as a energy conversion devices. TMDs such as molybdenum
[56]
binder in ceramics and other materials [57,58] . In the oil and disulfide (MoS ) and tungsten diselenide (WSe ) have been
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gas industry, Laponite is used as a drilling fluid additive used as substrates for neural stem cells (NSCs) and neuronal
to increase the viscosity of the fluid and prevent well cells, promoting their attachment and differentiation [66,67] .
collapse [59,60] . In addition, Laponite has been studied for its Furthermore, TMDs exhibit excellent electrical conductivity,
potential use in drug delivery and as a catalyst in various which makes them suitable for electrical stimulation in
chemical reactions [61,62] . neural tissue engineering. Electrical stimulation has been
shown to influence cell behavior, including cell migration,
2.1.6. Other types of 2D metallic nanomaterials differentiation, and neurite outgrowth .
[68]
Metal-organic frameworks (MOFs) are a class of porous Silicene, the silicon-based equivalent of graphene, has
materials composed of metal ions or clusters coordinated attracted considerable attention due to its remarkable
to organic ligands. They are characterized by a highly properties akin to graphene, primarily attributed to the
ordered and crystalline structure with a large surface presence of Dirac fermions. Unlike the perfectly flat
area and a network of interconnected pores. Due to structure of graphene, silicene displays atomic-scale
2
3
their unique properties, MOFs can be engineered to buckling, reflecting the hybridized sp -sp nature of its
3
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have specific characteristics that allow them to carry and hexagonal silicon lattice. Furthermore, the mixed sp -sp
release therapeutic agents efficiently. The porous structure hybridization of silicene enables excellent reactivity,
[69]
of MOFs enables the encapsulation of drugs within their making it highly amenable to chemical functionalization .
cavities or onto their surfaces. For instance, Yu et al. utilized It has been applied in research related to photothermal
[70]
a MOF loaded with small interfering RNA (siSOX9) and therapy, drug delivery, photoacoustic imaging, etc , and
retinoic acid, which was designed to respond to high it is predicted to be applied to neural tissue engineering
levels of oxidative stress (H O ) and release the loaded more as it is biocompatible due to the ubiquitous chemical
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cargos in the affected area, promoting neuron-directional constitution of silicon.
differentiation . As a result, the NPs effectively eliminated 2.2. Biocompatibility and neural cytotoxicity of 2D
[63]
reactive oxygen species (ROS) and prevented oxidative nanomaterials
damage to the newly formed neurons.
In vitro cytotoxicity assessment is crucial in the fabrication
Gold NPs (AuNPs) refer to tiny particles of gold with of 2D nanomaterial-based scaffolds for practical
sizes ranging from 1 to 100 nm. AuNPs exhibit unique biomedical applications, and thus, it is mandatory
optical, electronic, and catalytic properties due to their to investigate their toxicity before using them for
small size and high surface-to-volume ratio. AuNPs find in vivo applications. Therefore, numerous studies have
applications in various fields, including nanotechnology, been conducted to evaluate the cytotoxic effects of 2D
medicine, electronics, and catalysis. Especially, research nanomaterials on various cell types, as shown in Table 1.
on utilizing AuNPs as nanomedicine platforms is actively The results of cytotoxicity studies on 2D nanomaterials
conducted. Khongkow et al. combined the unique can vary significantly depending on several factors. Studies
functionalities of exosome-derived membranes with indicate that the biocompatibility of 2D nanomaterials may
synthetic AuNPs to create novel nanomaterials with brain- vary depending on the type of cells and materials used. For
targeting capabilities . Lavoie-Cardinal et al. introduced example, research findings indicate that the cytotoxicity of
[64]
an all-optical method for localized stimulation and BP nanosheets can vary among different fibroblast cell types,
monitoring of calcium (Ca ) signaling in neurons using namely, primary cultured normal human dermal fibroblasts
2+
AuNPs . While the use of 2D gold nanosheets (AuNSs) (NHDFs), mouse embryonic fibroblasts (NIH3T3), and
[65]
in neural tissue engineering has not been explored, their fibrosarcoma cells (HT1080). Specifically, the toxicity
unique physicochemical properties distinct from 3D NPs of BP nanosheets on HT1080 is higher than on NHDFs
make them a promising prospect for future application in and NIH3T3 cells . In addition, it is well known that the
[71]
this field. toxicity of graphene-based materials varies depending on

Volume 2 Issue 2 (2023) 4 https://doi.org/10.36922/msam.0620