Two-dimensional nanostructure-reinforced biodegradable polymeric nanocomposites for bone tissue engineering

Poly(propylene fumarate) Composite Scaffolds for Bone Tissue Engineering: Innovation in Fabrication Techniques and Artificial Intelligence Integration

Over the past three decades, the biodegradable polymer known as poly(propylene fumarate) (PPF) has been the subject of numerous research due to its unique properties. Its biocompatibility and controllable mechanical properties have encouraged numerous scientists to manufacture and produce a wide range of PPF-based materials for biomedical purposes. Additionally, the ability to tailor the degradation rate of the scaffold material to match the rate of new bone tissue formation is particularly relevant in bone tissue engineering, where synchronized degradation and tissue regeneration are critical for effective healing. This review thoroughly summarizes the advancements in different approaches for PPF and PPF-based composite scaffold preparation for bone tissue engineering. Additionally, the challenges faced by each approach, such as biocompatibility, degradation, mechanical features, and crosslinking, were emphasized, and the noteworthy benefits of the most pertinent synthesis strategies were highlighted. Furthermore, the synergistic outcome between tissue engineering and artificial intelligence (AI) was addressed, along with the advantages brought by the implication of machine learning (ML) as well as the revolutionary impact on regenerative medicines. Future advances in bone tissue engineering could be facilitated by the enormous potential for individualized and successful regenerative treatments that arise from the combination of tissue engineering and artificial intelligence. By assessing a patient's reaction to a certain drug and choosing the best course of action depending on the patient's genetic and clinical characteristics, AI can also assist in the treatment of illnesses. AI is also used in drug research and discovery, target identification, clinical trial design, and predicting the safety and effectiveness of novel medications. Still, there are ethical issues including data protection and the requirement for reliable data management systems. AI adoption in the healthcare sector is expensive, involving staff and facility investments as well as training healthcare professionals on its application.

Graphene/carbohydrate polymer composites as emerging hybrid materials in tumor therapy and diagnosis

Despite the introduction of various types of treatments for cancer control, cancer therapy faces several challenges such as aggressive behavior, heterogeneous characteristics, and the development of resistance. In contrast, the methods have depended on the creation and formulation of nanoparticles to impede tumor growth. Carbon nanoparticles have attracted considerable attention for cancer therapy, with graphene nanoparticles emerging as promising vehicles for delivering drugs and genes. Moreover, graphene composites can enhance immunotherapy, phototherapy, and combination therapies. Nonetheless, the biocompatibility and toxicity of graphene composites present difficulties. Consequently, this manuscript assesses the alteration of graphene nanocomposites using carbohydrate polymers. Altering graphene composites with carbohydrate polymers such as chitosan, hyaluronic acid, cellulose, and starch can enhance their efficacy in cancer treatment. Furthermore, graphene composites functionalized with carbohydrate polymers for tumor ablation induced by phototherapy. Graphene oxide and graphene quantum dots have been modified with carbohydrate polymers to enhance their therapeutic and diagnostic uses. These nanoparticles can transport gene therapy techniques like siRNA in the treatment of cancer. Despite the breakdown of these nanoparticles within the body, they maintain excellent biosafety and biocompatibility.

Application of loaded graphene oxide biomaterials in the repair and treatment of bone defects

Addressing bone defects is a complex medical challenge that involves dealing with various skeletal conditions, including fractures, osteoporosis (OP), bone tumours, and bone infection defects. Despite the availability of multiple conventional treatments for these skeletal conditions, numerous limitations and unresolved issues persist. As a solution, advancements in biomedical materials have recently resulted in novel therapeutic concepts. As an emerging biomaterial for bone defect treatment, graphene oxide (GO) in particular has gained substantial attention from researchers due to its potential applications and prospects. In other words, GO scaffolds have demonstrated remarkable potential for bone defect treatment. Furthermore, GO-loaded biomaterials can promote osteoblast adhesion, proliferation, and differentiation while stimulating bone matrix deposition and formation. Given their favourable biocompatibility and osteoinductive capabilities, these materials offer a novel therapeutic avenue for bone tissue regeneration and repair. This comprehensive review systematically outlines GO scaffolds' diverse roles and potential applications in bone defect treatment.

Sustainability in the green engineering of nanocomposites based on marine-derived polysaccharides and collagens: A review

Nanocomposites are sophisticated materials that incorporate nanostructures into matrix materials, such as polymers, ceramics and metals. Generally, the marine ecosystem exhibits severe variability in terms of light, temperature, pressure, and nutrient status, forcing the marine organisms to develop variable, complex and unique chemical structures to boost their competitiveness and chances of survival. Polymers sourced from marine creatures, such as chitin, chitosan, alginate, sugars, proteins, and collagen play a crucial role in the bioengineering field, contributing significantly to the development of nanostructures like nanoparticles, nanocomposites, nanotubes, quantum dots, etc. These nanostructures offer a wide array of features involving mechanical strength, thermal stability, electrical conductivity, barrier and optical characteristics compared to traditional composites. Notably, marine nanocomposites have distinctive roles in a wide spectrum of applications, among them anti-cancer, anti-microbial, antioxidant, cytotoxic, food packing, tissue engineering and catalytic actions. Sol-gel, hot pressing, chemical vapor deposition, catalytic decomposition, dispersion, melt intercalation, in situ intercalative polymerization, high-energy ball milling and template synthesis are common processes utilized in engineering nanocomposites. According to our literature survey and the Web of Science, chitosan, followed by cellulose, chitin and MAPs emerge as the most significant marine polymers utilized in the construction of nanocomposites. Taken together, the current manuscript underscores the biogenesis of nanocomposites, employing marine polymers using eco-friendly processes. Furthermore, significant emphasis in this area is needed to fully explore their capabilities and potential benefits. To the best of our knowledge, this manuscript stands as the first comprehensive review that discusses the role of marine-derived polymers in engineering nanocomposites for various applications.

Development of Light, Strong, and Water-Resistant PVA Composite Aerogels

A significant weakness of many organic and inorganic aerogels is their poor mechanical behaviour, representing a great impediment to their application. For example, polymer aerogels generally have higher ductility than silica aerogels, but their elastic modulus is considered too low. Herein, we developed extremely low loading (<1 wt%) 2D graphene oxide (GO) nanosheets modified poly (vinyl alcohol) (PVA) aerogels via a facile and environmentally friendly method. The aerogel shows a 9-fold increase in compressional modulus compared to a pure polymer aerogel. With a low density of 0.04 mg/mm3 and a thermal conductivity of only 0.035 W/m·K, it outperforms many commercial insulators and foams. As compared to a pure PVA polymer aerogel, a 170% increase in storage modulus is obtained by adding only 0.6 wt% GO nanosheets. The nanocomposite aerogel demonstrates strong fire resistance, with a 50% increase in burning time and little smoke discharge. After surface modification with 1H,1H,2H,2H-Perfluorodecyltriethoxysilane, the aerogel demonstrates water resistance, which is suitable for outdoor applications in which it would be exposed to precipitation. Our research demonstrates a new pathway for considerable improvement in the performance and application of polymer aerogels.

Current developments and future perspectives of nanotechnology in orthopedic implants: an updated review

Orthopedic implants are the most commonly used fracture fixation devices for facilitating the growth and development of incipient bone and treating bone diseases and defects. However, most orthopedic implants suffer from various drawbacks and complications, including bacterial adhesion, poor cell proliferation, and limited resistance to corrosion. One of the major drawbacks of currently available orthopedic implants is their inadequate osseointegration at the tissue-implant interface. This leads to loosening as a result of immunological rejection, wear debris formation, low mechanical fixation, and implant-related infections. Nanotechnology holds the promise to offer a wide range of innovative technologies for use in translational orthopedic research. Nanomaterials have great potential for use in orthopedic applications due to their exceptional tribological qualities, high resistance to wear and tear, ability to maintain drug release, capacity for osseointegration, and capability to regenerate tissue. Furthermore, nanostructured materials possess the ability to mimic the features and hierarchical structure of native bones. They facilitate cell proliferation, decrease the rate of infection, and prevent biofilm formation, among other diverse functions. The emergence of nanostructured polymers, metals, ceramics, and carbon materials has enabled novel approaches in orthopaedic research. This review provides a concise overview of nanotechnology-based biomaterials utilized in orthopedics, encompassing metallic and nonmetallic nanomaterials. A further overview is provided regarding the biomedical applications of nanotechnology-based biomaterials, including their application in orthopedics for drug delivery systems and bone tissue engineering to facilitate scaffold preparation, surface modification of implantable materials to improve their osteointegration properties, and treatment of musculoskeletal infections. Hence, this review article offers a contemporary overview of the current applications of nanotechnology in orthopedic implants and bone tissue engineering, as well as its prospective future applications.

The Utility of 3D Printing for Surgical Planning and Patient-Specific Implant Design in Maxillofacial Surgery: A Narrative Review

Maxillofacial reconstructive implants are typically created in standard shapes and have a widespread application in head and neck surgery. During surgical procedures, the implant must be correctly bent according to the architecture of the particular bones. Bending takes practice, especially for untrained surgeons. Furthermore, repeated bending may increase internal stress, resulting in fatigue in vivo under masticatory loading and an array of consequences, including implant failure. There is a risk of fracture, screw loosening, and bone resorption. Resorption, infection, and displacement are usually associated with the use of premade alloplastic implants and autogenous grafts. Recent technological breakthroughs have led to the use of patient-specific implants (PSIs) developed by computer-designed additive manufacturing in reconstructive surgery. The use of computer-designed three-dimensional (3D)-printed PSI allows for more precise restoration of maxillofacial deformities, avoiding the common difficulties associated with premade implants and increasing patient satisfaction. Additive manufacturing is something that refers to a group of additive manufacturing methods. This technique has been quickly used in a variety of surgical procedures. The exponential expansion of this technology can be attributed to its enormous surgical value. Adding 3D printing to a medical practice can be a rewarding experience with stunning results.

Synthesis and evaluation of poly(propylene fumarate)-grafted graphene oxide as nanofiller for porous scaffolds

In an effort to obtain porous scaffolds with improved mechanical properties and biocompatibility, the current study discusses nanocomposite materials based on poly(propylene fumarate)/N-vinyl pyrrolidone(PPF/NVP) networks reinforced with polymer-modified graphene oxide (GO@PPF). The GO@PPF nanofiller was synthesized through a facile and convenient surface esterification reaction, and the successful functionalization was demonstrated by complementary techniques such as FT-IR, XPS, TGA and TEM. The PPF/NVP/GO@PPF porous scaffolds obtained using NaCl as a porogen were further characterized in terms of morphology, mechanical properties, sol fraction, and in vitro degradability. SEM and nanoCT examinations of NaCl-leached samples revealed networks of interconnected pores, fairly uniform in size and shape. We show that the incorporation of GO@PPF in the polymer matrix leads to a significant enhancement in the mechanical properties, which we attribute to the formation of denser and more homogenous networks, as suggested by a decreased sol fraction for the scaffolds containing a higher amount of GO@PPF. Moreover, the surface of mineralized PPF/NVP/GO@PPG scaffolds is uniformly covered in hydroxyapatite-like crystals having a morphology and Ca/P ratio similar to bone tissue. Furthermore, the preliminary biocompatibility assessment revealed a good interaction between PPF/PVP/GO@PPF scaffolds and murine pre-osteoblasts in terms of cell viability and proliferation.

Investigation of physical, mechanical and biological properties of polyhydroxybutyrate-chitosan/graphene oxide nanocomposite scaffolds for bone tissue engineering applications

Mechanical properties appropriate to native tissues, as an essential component in bone tissue engineering scaffolds, plays a significant role in tissue formation. In the current study, Poly-3 hydroxybutyrate-chitosan (PC) scaffolds reinforced with graphene oxide (GO) were made by the electrospinning method. The addition of GO led to a decrease in fibers diameter, an increase in thermal capacity and an improvement in the surface hydrophilicity of nanocomposite scaffolds. A significant increase in the mechanical properties of PC/GO (PCG) nanocomposite scaffolds was achieved due to the inherent strength of GO as well as its uniform dispersion throughout the polymeric matrix owing to hydrogen bonding and polar interactions. Also, lower biological degradation of the scaffolds (~30% in 100 days) due to the presence of GO provides essential mechanical support for bone regeneration. In addition, the bioactivity results showed that GO reinforcement significantly increases the biomineralization on the surface of the scaffolds. Evaluating cell adhesion and proliferation, as well as ALP activity of MG-63 cells on PC and PCG scaffolds indicated the positive effect of GO on scaffolds' biocompatibility. Overall, the improvement of physicochemical, mechanical, and biological properties of GO-reinforced scaffolds shows the potential of PCG nanocomposite scaffolds for bone tissue engineering.

Gaussian Curvature Effects on Graphene Quantum Dots

In the last few years, much attention has been paid to the exotic properties that graphene nanostructures exhibit, especially those emerging upon deforming the material. Here we present a study of the mechanical and electronic properties of bent hexagonal graphene quantum dots employing density functional theory. We explore three different kinds of surfaces with Gaussian curvature exhibiting different shapes-spherical, cylindrical, and one-sheet hyperboloid-used to bend the material, and several boundary conditions regarding what atoms are forced to lay on the chosen surface. In each case, we study the curvature energy and two quantum regeneration times (classic and revival) for different values of the curvature radius. A strong correlation between Gaussian curvature and these regeneration times is found, and a special divergence is observed for the revival time for the hyperboloid case, probably related to the pseudo-magnetic field generated by this curvature being capable of causing a phase transition.

Tuning Peptide-Based Hydrogels: Co-Assembly with Composites Driving the Highway to Technological Applications

Self-assembled peptide-based gels provide several advantages for technological applications. Recently, the co-assembly of gelators has been a strategy to modulate and tune gel properties and even implement stimuli-responsiveness. However, it still comprises limitations regarding the required library of compounds and outcoming properties. Hence, efforts have been made to combine peptide-based gels and (in)organic composites (e.g., magnetic nanoparticles, metal nanoparticles, liposomes, graphene, silica, clay, titanium dioxide, cadmium sulfide) to endow stimuli-responsive materials and achieve suitable properties in several fields ranging from optoelectronics to biomedical. Herein, we discuss the recent developments with composite peptide-based gels including the fabrication, tunability of gels' properties, and challenges on (bio)technological applications.

Feedstock design for quality biomaterials

Feedstock design is crucial for lignocellulosic biomass use. Current strategies for feedstock design cannot be readily applied to improve the quality of biomass-based materials, limiting the sustainability and economics of lignocellulosic biorefineries. Recent studies have advanced the understanding of biomass structure-property relationships and discovered several characteristics, such as molecular weight, uniformity, linkage profile, and functional groups, that are critical for manufacturing diverse quality biomaterials. These discoveries call for fundamentally different strategies for feedstock development. Such strategies need to rediscover the roles of monolignol biosynthesis enzymes and leverage lignin polymerization enzymes to achieve precise control of lignin molecular structure. These innovations could transform biomass into feedstock for high-quality biomaterials, addressing essential environmental challenges and empowering the bioeconomy.

Multifunctional Filter Membranes Based on Self-Assembled Core-Shell Biodegradable Nanofibers for Persistent Electrostatic Filtration through the Triboelectric Effect

The massive production of polymer-based respiratory masks during the COVID-19 pandemic has rekindled the issue of environmental pollution from nonrecyclable plastic waste. To mitigate this problem, conventional filters should be redesigned with improved filtration performance over the entire operational life while also being naturally degradable at the end. Herein, we developed a functional and biodegradable polymeric filter membrane consisting of a polybutylene adipate terephthalate (PBAT) matrix blended with cetyltrimethylammonium bromide (CTAB) and montmorillonite (MMT) clay, whose surface properties have been modified through cation exchange reactions for good miscibility with PBAT in an organic solvent. Particularly, the spontaneous evolution of a partial core-shell structure (i.e., PBAT core encased by CTAB-MMT shell) during the electrospinning process amplified the triboelectric effect as well as the antibacterial/antiviral activity that was not observed in naive PBAT. Unlike the conventional face mask filter that relies on the electrostatic adsorption mechanism, which deteriorates over time and/or due to external environmental factors, the PBAT@CTAB-MMT nanofiber membrane (NFM)-based filter continuously retains electrostatic charges on the surface due to the triboelectric effect of CTAB-MMT. As a result, the PBAT@CTAB-MMT NFM-based filter showed high filtration efficiencies (98.3%, PM_0.3) even at a low differential pressure of 40 Pa or less over its lifetime. Altogether, we not only propose an effective and practical solution to improve the performance of filter membranes while minimizing their environmental footprint but also provide valuable insight into the synergetic functionalities of organic-inorganic hybrid materials for applications beyond filter membranes.

Recent Advances of Chitosan Formulations in Biomedical Applications

Chitosan, a naturally abundant cationic polymer, is chemically composed of cellulose-based biopolymers derived by deacetylating chitin. It offers several attractive characteristics such as renewability, hydrophilicity, biodegradability, biocompatibility, non-toxicity, and a broad spectrum of antimicrobial activity towards gram-positive and gram-negative bacteria as well as fungi, etc., because of which it is receiving immense attention as a biopolymer for a plethora of applications including drug delivery, protective coating materials, food packaging films, wastewater treatment, and so on. Additionally, its structure carries reactive functional groups that enable several reactions and electrochemical interactions at the biomolecular level and improves the chitosan’s physicochemical properties and functionality. This review article highlights the extensive research about the properties, extraction techniques, and recent developments of chitosan-based composites for drug, gene, protein, and vaccine delivery applications. Its versatile applications in tissue engineering and wound healing are also discussed. Finally, the challenges and future perspectives for chitosan in biomedical applications are elucidated.

Carbon nanomaterials for drug delivery and tissue engineering

Carbon nanomaterials are some of the state-of-the-art materials used in drug-delivery and tissue-engineering research. Compared with traditional materials, carbon nanomaterials have the advantages of large specific surface areas and unique properties and are more suitable for use in drug delivery and tissue engineering after modification. Their characteristics, such as high drug loading and tissue loading, good biocompatibility, good targeting and long duration of action, indicate their great development potential for biomedical applications. In this paper, the synthesis and application of carbon dots (CDs), carbon nanotubes (CNTs) and graphene in drug delivery and tissue engineering are reviewed in detail. In this review, we discuss the current research focus and existing problems of carbon nanomaterials in order to provide a reference for the safe and effective application of carbon nanomaterials in drug delivery and tissue engineering.

Nano-bio interactions of 2D molybdenum disulfide

Two-dimensional (2D) molybdenum disulfide (MoS2) is an ultrathin nanomaterial with a high degree of anisotropy, surface-to-volume ratio, chemical functionality and mechanical strength. These properties together enable MoS2 to emerge as a potent nanomaterial for diverse biomedical applications including drug delivery, regenerative medicine, biosensing and bioelectronics. Thus, understanding the interactions of MoS2 with its biological interface becomes indispensable. These interactions, referred to as "nano-bio" interactions, play a key role in determining the biocompatibility and the pathways through which the nanomaterial influences molecular, cellular and biological function. Herein, we provide a critical overview of the nano-bio interactions of MoS2 and emphasize on how these interactions dictate its biomedical applications including intracellular trafficking, biodistribution and biodegradation. Also, a critical evaluation of the interactions of MoS2 with proteins and specific cell types such as immune cells and progenitor/stem cells is illustrated which governs the short-term and long-term compatibility of MoS2-based biomedical devices.

Quantum Revivals in Curved Graphene Nanoflakes

Graphene nanostructures have attracted a lot of attention in recent years due to their unconventional properties. We have employed Density Functional Theory to study the mechanical and electronic properties of curved graphene nanoflakes. We explore hexagonal flakes relaxed with different boundary conditions: (i) all atoms on a perfect spherical sector, (ii) only border atoms forced to be on the spherical sector, and (iii) only vertex atoms forced to be on the spherical sector. For each case, we have analysed the behaviour of curvature energy and of quantum regeneration times (classical and revival) as the spherical sector radius changes. Revival time presents in one case a divergence usually associated with a phase transition, probably caused by the pseudomagnetic field created by the curvature. This could be the first case of a phase transition in graphene nanostructures without the presence of external electric or magnetic fields.

Two-dimensional nanomaterials-added dynamism in 3D printing and bioprinting of biomedical platforms: Unique opportunities and challenges

The nanomaterials research spectrum has seen the continuous emergence of two-dimensional (2D) materials over the years. These highly anisotropic and ultrathin materials have found special attention in developing biomedical platforms for therapeutic applications, biosensing, drug delivery, and regenerative medicine. Three-dimensional (3D) printing and bioprinting technologies have emerged as promising tools in medical applications. The convergence of 2D nanomaterials with 3D printing has extended the application dynamics of available biomaterials to 3D printable inks and bioinks. Furthermore, the unique properties of 2D nanomaterials have imparted multifunctionalities to 3D printed constructs applicable to several biomedical applications. 2D nanomaterials such as graphene and its derivatives have long been the interest of researchers working in this area. Beyond graphene, a range of emerging 2D nanomaterials, such as layered silicates, black phosphorus, transition metal dichalcogenides, transition metal oxides, hexagonal boron nitride, and MXenes, are being explored for the multitude of biomedical applications. Better understandings on both the local and systemic toxicity of these materials have also emerged over the years. This review focuses on state-of-art 3D fabrication and biofabrication of biomedical platforms facilitated by 2D nanomaterials, with the comprehensive summary of studies focusing on the toxicity of these materials. We highlight the dynamism added by 2D nanomaterials in the printing process and the functionality of printed constructs.

A Study of the Key Factors on Production of Graphene Materials from Fe-Lignin Nanocomposites through a Molecular Cracking and Welding (MCW) Method

In this work, few-layer graphene materials were produced from Fe-lignin nanocomposites through a molecular cracking and welding (MCW) method. MCW process is a low-cost, scalable technique to fabricate few-layer graphene materials. It involves preparing metal (M)-lignin nanocomposites from kraft lignin and a transition metal catalyst, pretreating the M-lignin composites, and forming of the graphene-encapsulated metal structures by catalytic graphitization the M-lignin composites. Then, these graphene-encapsulated metal structures are opened by the molecule cracking reagents. The graphene shells are peeled off the metal core and simultaneously welded and reconstructed to graphene materials under a selected welding reagent. The critical parameters, including heating temperature, heating time, and particle sizes of the Fe-lignin composites, have been explored to understand the graphene formation mechanism and to obtain the optimized process parameters to improve the yield and selectivity of graphene materials.

An Update on Graphene-Based Nanomaterials for Neural Growth and Central Nervous System Regeneration

Thanks to their reduced size, great surface area, and capacity to interact with cells and tissues, nanomaterials present some attractive biological and chemical characteristics with potential uses in the field of biomedical applications. In this context, graphene and its chemical derivatives have been extensively used in many biomedical research areas from drug delivery to bioelectronics and tissue engineering. Graphene-based nanomaterials show excellent optical, mechanical, and biological properties. They can be used as a substrate in the field of tissue engineering due to their conductivity, allowing to study, and educate neural connections, and guide neural growth and differentiation; thus, graphene-based nanomaterials represent an emerging aspect in regenerative medicine. Moreover, there is now an urgent need to develop multifunctional and functionalized nanomaterials able to arrive at neuronal cells through the blood-brain barrier, to manage a specific drug delivery system. In this review, we will focus on the recent applications of graphene-based nanomaterials in vitro and in vivo, also combining graphene with other smart materials to achieve the best benefits in the fields of nervous tissue engineering and neural regenerative medicine. We will then highlight the potential use of these graphene-based materials to construct graphene 3D scaffolds able to stimulate neural growth and regeneration in vivo for clinical applications.

Graphene-Based Nanocomposites: Synthesis, Mechanical Properties, and Characterizations

Graphene-based nanocomposites possess excellent mechanical, electrical, thermal, optical, and chemical properties. These materials have potential applications in high-performance transistors, biomedical systems, sensors, and solar cells. This paper presents a critical review of the recent developments in graphene-based nanocomposite research, exploring synthesis methods, characterizations, mechanical properties, and thermal properties. Emphasis is placed on characterization techniques and mechanical properties with detailed examples from recent literature. The importance of characterization techniques including Raman spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) for the characterization of graphene flakes and their composites were thoroughly discussed. Finally, the effect of graphene even at very low loadings on the mechanical properties of the composite matrix was extensively reviewed.

Nanoscale Drug Delivery Systems for Glaucoma: Experimental and In Silico Advances

In this review, nanoscale-based drug delivery systems, particularly in relevance to the antiglaucoma drugs, have been discussed. In addition to that, the latest computational/in silico advances in this field are examined in brief. Using nanoscale materials for drug delivery is an ideal option to target tumours, and the drug can be released in areas of the body where traditional drugs may fail to act. Nanoparticles, polymeric nanomaterials, single-wall carbon nanotubes (SWCNTs), quantum dots (QDs), liposomes and graphene are the most important nanomaterials used for drug delivery. Ocular drug delivery is one of the most common and difficult tasks faced by pharmaceutical scientists because of many challenges like circumventing the blood-retinal barrier, corneal epithelium and the blood-aqueous barrier. Authors found compelling empirical evidence of scientists relying on in-silico approaches to develop novel drugs and drug delivery systems for treating glaucoma. This review in nanoscale drug delivery systems will help us understand the existing queries and evidence gaps and will pave the way for the effective design of novel ocular drug delivery systems.

Scavenging of OH and OOH radicals by polyradicals of small polycyclic aromatic hydrocarbons

The hydroxyl and peroxyl radicals, particularly the former, occur abundantly and damage almost all types of materials. Polycyclic aromatic hydrocarbons (PAHs) and their polyradicals (all hydrogens removed) have been considered as models for graphene in some recent studies. Geometries of different adducts of polyradicals of two small PAHs having four and nine benzene rings with an OH or OOH radical each were optimized employing unrestricted density functional theory and two different density functionals. The ground states of all the adducts involving the PAHs had doublet spin multiplicity while those involving the polyradicals had doublet, quartet, sextet, or octet spin multiplicity that was decided on the basis of calculated minimum total energies for optimized geometries. Binding energies of the adducts of an OH or OOH radical at the different sites of the polyradicals of PAHs showed that the OH radical would bind with these systems much more strongly than the OOH radical while both the radicals would bind much more strongly with the polyradicals than with the PAHs. Furthermore, both the OH and OOH radicals are found to bind at the edges of the polyradicals much more strongly than at their interior sites. It is shown that polyradicals can serve as efficient scavengers of OH and OOH radicals and therefore, these materials can be used to protect both biological and non-biological systems from damage due to reactions with these radicals.

Polarization influences the evolution of nucleobase-graphene interactions

In recent years, graphene has attracted attention from researchers as an atomistically thin solid state material for the study on the self-assembly of nucleobases. Non-covalent interactions between nucleobases and graphene sheets play a fundamental role in understanding the self-assembly of nucleobases on the graphene sheet. A fundamental understanding of the effect of molecular polarizability on these non-covalent interactions between the nucleobases and the underlying graphene sheet is absent in the literature. In this paper, we present the results from polarizable molecular dynamics simulation studies to understand the effect of polarization on the strength of non-covalent interactions. To this end, we report the development of Drude parameters for describing the polarizable graphene sheet. The developed parameters were used to study the self-aggregation phenomenon of nucleobases on a graphene support. We observe a significant change in the interaction patterns upon the inclusion of polarization into the system, with polarizable simulations yielding results that closely resemble the experimental studies. Two of the key observations were the probability of the formation of stacks in guanine-rich systems, and the spontaneous formation of H-bonded structures over the graphene sheet, which allude to the importance of the DNA sequence and composition. Both these effects were not observed in the additive simulations. The present study sheds light on the effect of polarization on the adsorption of DNA nucleobases on a graphene sheet, but the methodology can be extended to include a variety of small molecules and complete DNA strands.

Functionalized multi-walled carbon nanotubes and hydroxyapatite nanorods reinforced with polypropylene for biomedical application

Modified multi-walled carbon nanotubes (f-MWCNTs) and hydroxyapatite nanorods (n-HA) were reinforced into polypropylene (PP) with the support of a melt compounding approach. Varying composition of f-MWCNTs (0.1–0.3 wt.%) and nHA (15–20 wt.%) were reinforced into PP, to obtain biocomposites of different compositions. The morphology, thermal and mechanical characteristics of PP/n-HA/f-MWCNTs were observed. Tensile studies reflected that the addition of f-MWCNTs is advantageous in improving the tensile strength of PP/n-HA nanocomposites but decreases its Young’s modulus significantly. Based on the thermal study, the f-MWCNTs and n-HA were known to be adequate to enhance PP’s thermal and dimensional stability. Furthermore, MTT studies proved that PP/n-HA/f-MWCNTs are biocompatible. Consequently, f-MWCNTs and n-HA reinforced into PP may be a promising nanocomposite in orthopedics industry applications such as the human subchondral bone i.e. patella and cartilage and fabricating certain light-loaded implants.

Modified silicates and carbon nanotubes for immobilization of lipase from Rhizomucor miehei: Effect of support and immobilization technique on the catalytic performance of the immobilized biocatalysts

Lipase from Rhizomucor miehei (RML) was covalently immobilized on different supports, two silica gels and two carbon nanotube samples, using two different strategies. RML was immobilized on 3-carboxypropyl silica gel (RML@Si-COOH) and multi-wall carbon nanotubes containing carboxylic acid functionalities (RML@MCNT-COOH) using a two-step carbodiimide activation/immobilization reaction. Moreover, the enzyme was also immobilized on 3-aminopropyl silica (RML@Si-Glu) and single-wall carbon nanotubes functionalized with 3-APTES and activated with glutaraldehyde (RML@SCNT-Glu). Before and after RML immobilization, the structurel properties of supports were characterized and compared in detail. After immobilization, the expressed activities were 36.9, 90.2, 16.9, and 26.1 % for RML@Si-COOH, RML@Si-Glu, RML@MCNT-COOH, and RML@SCNT-Glu, respectively. The kinetic parameters of free and immobilized RML samples were determined for three substrates, p-nitrophenyl acetate, p-nitrophenyl butyrate and p-nitrophenyl palmitate, and RML@Si-Glu showed higher catalytic efficiency than the other immobilized RML samples. RML@Si-COOH, RML@Si-Glu, RML@MCNT-COOH, and RML@SCNT-Glu exhibited 5.8, 7.6, 4.2 and 4.6 folds longer half-life values than those of the free enzyme at pH 7.5 and 40 °C. Recyclability studies showed that all the immobilized RML biocatalysts retained over 90 % of their initial activities after ten cycles in the hydrolysis of p-nitrophenyl butyrate.

Sol-gel synthesis of 2-dimensional TiO2: self-assembly of Ti-oxoalkoxy-acetate complexes by carboxylate ligand directed condensation

2-Dimensional (2D) metal oxides have many potential industrial applications including heterogeneous catalysis, water splitting, renewable energy conversion, supercapacitor applications, biomaterials, gas separation and gas storage. Herein we report a simple and scalable method for the preparation of 2D TiO₂ nanostructures by reaction of titanium isopropoxide with acetic acid at 333 K in isopropanol, followed by calcination at 673 K to remove the organic ligands. Both the products and reaction intermediates have been studied using electron microscopy, X-ray diffraction, N₂ physisorption, nuclear magnetic resonance, thermogravimetric analysis, and X-ray photoelectron, Raman, and infrared spectroscopy. The anisotropic condensation of the planar Ti₆O₄(OⁱPr)₈(OAc)₈ complex is believed to be responsible for the formation of the 2D structure, where OⁱPr and OAc represent isopropoxide and acetate ligands, respectively. This research demonstrates that the metal complexes are promising building blocks for desired architectures, and the self-assembly of an acetate bidentate ligand is a versatile tool for manipulating the shape of final products.

The effect of adding graphene oxide nanoplatelets to Portland cement: Potential for dental applications

Background:

The potential of graphene-based materials to improve the physiomechanical properties of Portland cement-based materials without compromising biocompatibility is of interest to dental researchers and remains to be discovered.

Aim:

This study investigated the effects of adding graphene oxide nanoplatelets (GONPs) on the surface microhardness and biocompatibility of Portland cement.

Materials and Methods:

Three prototype Portland cement powder formulations were prepared by adding 0, 1, and 3 wt % GONPs in powder form to Portland cement. Prototype cement specimens were in the form of disks, with a diameter of 10 mm and a thickness of 2 mm. In experiment 1, surface microhardness was measured using the through indenter viewing hardness tester, 20 surface hardness values were obtained from all specimens. In experiment 2, Balb/C 3T3 fibroblasts were cultured with the material disks and the viability of cells was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.

Statistical Analysis:

The data were analyzed using the analysis of variance followed by Dunnett test (α = 0.05) or Tukey test (α = 0.05).

Results:

In response to material disks, the addition of 1 wt % GONPs had a proliferative effect on cells at day 3 and day 7 with a significant difference from the control. The addition of 3 wt % GONPs showed a remarkable increase in surface microhardness; however, it exhibited initial cytotoxicity.

Conclusions:

The addition of 1 wt % GONPs to Portland cement improved surface microhardness without compromising biocompatibility; therefore, it has a greater potential for dental applications. The results of this work give other researchers leads in future assessments of this prototype material.

Sublethal exposure of small few-layer graphene promotes metabolic alterations in human skin cells

Small few-layer graphene (sFLG), a novel small-sized graphene-related material (GRM), can be considered as an intermediate degradation product of graphene. GRMs have a promising present and future in the field of biomedicine. However, safety issues must be carefully addressed to facilitate their implementation. In the work described here, the effect of sub-lethal doses of sFLG on the biology of human HaCaT keratinocytes was examined. A one-week treatment of HaCaTs with sub-lethal doses of sFLG resulted in metabolome remodeling, dampening of the mitochondrial function and a shift in the redox state to pro-oxidant conditions. sFLG raises reactive oxygen species and calcium from 24 h to one week after the treatment and this involves the activation of NADPH oxidase 1. Likewise, sFLG seems to induce a shift from oxidative phosphorylation to glycolysis and promotes the use of glutamine as an alternative source of energy. When sub-toxic sFLG exposure was sustained for 30 days, an increase in cell proliferation and mitochondrial damage were observed. Further research is required to unveil the safety of GRMs and degradation-derived products before their use in the workplace and in practical applications.

Degradation-by-design: how chemical functionalization enhances the biodegradability and safety of 2D materials

A large number of graphene and other 2D materials are currently used for the development of new technologies, increasingly entering different industrial sectors. Interrogating the impact of such 2D materials on health and environment is crucial for both modulating their potential toxicity in living organisms and eliminating them from the environment. In this context, understanding if 2D materials are bio-persistent is mandatory. In this review we describe the importance of biodegradability and decomposition of 2D materials. We initially cover the biodegradation of graphene family materials, followed by other emerging classes of 2D materials including transition metal dichalcogenides and oxides, Xenes, Mxenes and other non-metallic 2D materials. We explain the role of defects and functional groups, introduced onto the surface of the materials during their preparation, and the consequences of chemical functionalization on biodegradability. In strong relation to the chemistry on 2D materials, we describe the concept of "degradation-by-design" that we contributed to develop, and which concerns the covalent modification with appropriate molecules to enhance the biodegradability of 2D materials. Finally, we cover the importance of designing new biodegradable 2D conjugates and devices for biomedical applications as drug delivery carriers, in bioelectronics, and tissue engineering. We would like to highlight that the biodegradation of 2D materials mainly depends on the type of material, the chemical functionalization, the aqueous dispersibility and the redox potentials of the different oxidative environments. Biodegradation is one of the necessary conditions for the safe application of 2D materials. Therefore, we hope that this review will help to better understand their biodegradation processes, and will stimulate the chemists to explore new chemical strategies to design safer products, composites and devices containing 2D materials.

Hydrodynamic slip can align thin nanoplatelets in shear flow

The large-scale processing of nanomaterials such as graphene and MoS2 relies on understanding the flow behaviour of nanometrically-thin platelets suspended in liquids. Here we show, by combining non-equilibrium molecular dynamics and continuum simulations, that rigid nanoplatelets can attain a stable orientation for sufficiently strong flows. Such a stable orientation is in contradiction with the rotational motion predicted by classical colloidal hydrodynamics. This surprising effect is due to hydrodynamic slip at the liquid-solid interface and occurs when the slip length is larger than the platelet thickness; a slip length of a few nanometers may be sufficient to observe alignment. The predictions we developed by examining pure and surface-modified graphene is applicable to different solvent/2D material combinations. The emergence of a fixed orientation in a direction nearly parallel to the flow implies a slip-dependent change in several macroscopic transport properties, with potential impact on applications ranging from functional inks to nanocomposites.

Fire-safe unsaturated polyester resin nanocomposites based on MAX and MXene: a comparative investigation of their properties and mechanism of fire retardancy

Recently, MXene, as a novel graphene-like nanomaterial, has been found to bestow good flame-retardant and smoke-suppression properties to polymers mainly due to the physical barrier effect of its 2D nanosheets. However, a comprehensive investigation of its chemical components as an important factor for these properties has not been conducted to date. To address this issue, herein, MXene (Ti₃C₂T_x) and MAX (Ti₃AlC₂) were introduced into unsaturated polyester resin (UPR) at same amounts (2.0 wt%). Their structures are different (multilayer for MXene and bulk for MAX), but the chemical components are similar; therefore, it is important to study the influence of the chemical components of MXene on the fire-safety properties of polymers. In this study, 2 wt% MAX was added to the UPR, and the peak heat release rate (PHRR), the total smoke production (TSP), and carbon monoxide production (COP) of the resulting material were reduced by 11.04%, 19.08%, and 15.79%, respectively; these findings demonstrate the important role of the chemical components of MAX: Ti exerts a catalytic attenuation effect on the UPR nanocomposites during combustion. Moreover, a better fire-safety property of the MXene/UPR nanocomposites (reduction of PHRR by 29.56%, TSP by 25.26%, and COP by 31.58%) than that of the MAX/UPR nanocomposites was achieved, which was due to the physical barrier effect of the MXene nanosheets. This study verifies that in addition to the physical barrier effect, the chemical components play a very important role in the fire safety enhancement of MXene-based nanocomposites.

Directly writing flexible temperature sensor with graphene nanoribbons for disposable healthcare devices

A flexible temperature sensor is developed by directly writing or mask spraying commonly-used paper with graphene nanoribbon ink. The sensor is ultralow cost, degradable, and highly promising as a disposable device for personal healthcare.

Development of hydrophobic reduced graphene oxide as a new efficient approach for photochemotherapy

Nowadays, chemotherapy is one of the crucial and common therapies in the world. So far, it has been revealed to be highly promising, yet patients suffer from the consequences of severe negative medical dosages. In order to overcome these issues, the enhancement of photothermal chemotherapy with reduced graphene oxide (rGO) as a photothermal agent (PTA) is widely utilised in current medical technologies. This is due to its high near-infrared region (NIR) response, in vitro or in vivo organism biocompatibility, low risk of side effects, and effective positive results. Moreover, rGO not only has the ability to ensure that selective cancer cells have a higher mortality rate but can also improve the growth rate of recovering tissues that are untouched by necrosis and apoptosis. These two pathways are specific diverse modalities of cell death that are distinguished by cell membrane disruption and deoxyribonucleic acid (DNA) disintegration of the membrane via phosphatidylserine exposure in the absence of cell membrane damage. Therefore, this review aimed to demonstrate the recent achievements in the modification of rGO nanoparticles as a PTA as well as present a new approach for performing photochemotherapy in the clinical setting.

rGO of QD-rGO nanocomposite could absorb and convert into heat when harvested under NIR radiation, resulting cell death with reduction of fluorescence.

Engineered 3D Polymer and Hydrogel Microenvironments for Cell Culture Applications

The realization of biomimetic microenvironments for cell biology applications such as organ-on-chip, in vitro drug screening, and tissue engineering is one of the most fascinating research areas in the field of bioengineering. The continuous evolution of additive manufacturing techniques provides the tools to engineer these architectures at different scales. Moreover, it is now possible to tailor their biomechanical and topological properties while taking inspiration from the characteristics of the extracellular matrix, the three-dimensional scaffold in which cells proliferate, migrate, and differentiate. In such context, there is therefore a continuous quest for synthetic and nature-derived composite materials that must hold biocompatible, biodegradable, bioactive features and also be compatible with the envisioned fabrication strategy. The structure of the current review is intended to provide to both micro-engineers and cell biologists a comparative overview of the characteristics, advantages, and drawbacks of the major 3D printing techniques, the most promising biomaterials candidates, and the trade-offs that must be considered in order to replicate the properties of natural microenvironments.

Hema-Functionalized Graphene Oxide: a Versatile Nanofiller for Poly(Propylene Fumarate)-Based Hybrid Materials

Poly(propylene fumarate) (PPF) is a linear unsaturated polyester which has been widely investigated for tissue engineering due to its good biocompatibility and biodegradability. In order to extend the range of possible applications and enhance its mechanical properties, current approaches consist in the incorporation of various fillers or obtaining blends with other polymers. In the current study we designed a reinforcing agent based on carboxylated graphene oxide (GO-COOH) grafted with 2-hydroxyethyl methacrylate (GO@HEMA) for poly(propylene fumarate)/poly(ethylene glycol) dimethacrylate (PPF/PEGDMA), in order to enhance the nanofiller adhesion and compatibility with the polymer matrix, and in the same time to increase the crosslinking density. The covalent modification of GO-COOH was proved by Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and Raman spectroscopy. The mechanical properties, water uptake capacity, morphology, biodegradability, mineralization and in vitro cytotoxicity of PPF/PEGDMA hybrid materials containing GO@HEMA were investigated. A 14-fold increase of the compressive modulus and a 2-fold improvement in compressive strength were observed after introduction of the nanofiller. Moreover, the decrease in sol fraction and solvent swelling in case of the hybrid materials containing GO@HEMA suggests an increase of the crosslinking density. SEM images illustrate an exfoliated structure at lower nanofiller content and a tendency for agglomeration at higher concentrations. Finally, the synthesized hybrid materials proved non-cytotoxic to murine pre-osteoblast cells and induced the formation of hydroxyapatite crystals under mineralization conditions.

Bisphosphonate-Functionalized Scaffolds for Enhanced Bone Regeneration

The local sustained release of bioactive substances are attracting increasing attention in bone tissue engineering, which is beneficial to bone tissue formation and helps to improve the bone ingrowth ability of a scaffold. Bisphosphonates (BPs), as a representative kind of osteoclast inhibitors, are proven to possess excellent osteogenic induction capability. Accordingly, various physical and chemical strategies are developed to functionalize bone tissue scaffolds with BPs to achieve controlled release profiles. Compared with traditional treatment modalities, local release of BPs from these composite scaffolds will contribute to continuous bone integration without the risk of many complications. This review explores the molecular mechanisms of BPs on bone metabolism and analyzes the appropriate concentrations of BPs that promote bone regeneration. The advanced BP loading strategies, implant modification technologies, and BP-loaded composite scaffolds based on different matrices are summarized. Finally, the latest advances and the future development of BP-modified scaffolds for enhanced bone regeneration are discussed. This article provides leading-edge design strategies of the BP-functionalized bone engineering scaffolds for improved bone repairability.

Fabrication of bimodal open-porous poly (butylene succinate)/cellulose nanocrystals composite scaffolds for tissue engineering application

The design of porous tissue engineering scaffold with multiscale open-pore architecture (i.e., bimodal structure) promotes cell attachment and growth, which facilitates nutrient and oxygen diffusion. In this study, a porous poly (butylene succinate) (PBS)/cellulose nanocrystals (CNCs) composite scaffold with a well-defined controllable bimodal open-pore interconnected structure was successfully fabricated. The bimodal open-porous scaffold architecture was designed by synergistic control of temperature variation and a two-step depressurization in a supercritical carbon dioxide (Sc-CO₂) foaming process. The microstructure and properties of the bimodal open-porous PBS/CNCs scaffold, such as morphology, open porosity, hydrophilic and degradation performance, and mechanical compression properties, were analyzed. In the experiments, the scaffold with unimodal pore structure was used for comparison. The results showed that the bimodal open-porous PBS5 scaffold displayed a well-defined bimodal open-pore structure composed of large pore (~68.9 μm in diameter) and small pore (~11.0 μm in diameter), with a high open porosity (~95.2%). In addition, the scaffolds exhibited good mechanical compressive properties (compressive strength of 2.76 MPa at 50% strain), hydrophilicity (water contact angle of 71.7 °C) and in vitro degradation rate. Moreover, in vitro biocompatibility was determined with NIH-3T3 fibroblast cells using MTT assay and live/dead cell viability assay. Results indicated that the obtained bimodal open-porous scaffolds had a good biocompatibility and the viability of cells grown on the scaffolds reached up to 98% after 7th day of culture. Therefore, our work provides new insights into the use of biodegradable polymeric composite scaffolds with bimodal open-pore structure and balanced properties in tissue engineering.

Nanofilm generated non-pharmacological anabolic bone stimulus

Stimulus-responsive nanomaterials have mainly been employed to ablate or destroy tissues or to facilitate controlled release of drugs or biologics. Herein, we demonstrate the potential of stimulus-responsive nanomaterials to promote tissue regeneration via a non-pharmacological and noninvasive strategy. Thin nanofilms of an optically-absorbing organic dye or nanoparticle (single-walled graphene nanoribbons [SWOGNR]) were placed over (without touching the skin) a rodent femoral fracture site. A nanosecond pulsed near-infrared laser diode was employed to generate photoacoustic (PA) signals from the nanofilms. X-ray micro-computed tomography (microCT), histology, and mechanical testing results showed that daily PA stimulations of upto 45 min for 6 weeks (complete fracture healing) do not adversely affect bone regeneration and quality. Further, microCT and histological analysis showed 10 min daily stimulation for 2 weeks significantly increases bone quantity at the fracture sites of rats exposed to the nanoparticle-generated PA signals. In these rats, up to threefold increase in bone volume to callus volume ratio and twofold increase in bone mineral density within the callus were noted, compared to rats that were not exposed to the photoacoustic signals. The results taken together indicate that nanofilm-generated photoacoustic signals serve as an anabolic stimulus for bone regeneration. The results, in conjugation with the ability of these nanofilms to serve as PA contrast agents, present opportunities toward the development of integrated noninvasive imaging and noninvasive or invasive treatment strategies for bone loss due to disease or trauma.

Enhanced Osteogenesis by Molybdenum Disulfide Nanosheet Reinforced Hydroxyapatite Nanocomposite Scaffolds

The advances in the arena of biomedical engineering enable us to fabricate novel biomaterials that provide a suitable platform for rapid bone regeneration. Herein, we have investigated the in vitro and in vivo osteogenic differentiation, proliferation, and bone regeneration capability of molybdenum disulfide nanosheets (MoS₂NSs) reinforced HAP nanocomposite scaffolds. The MG-63 cells were incubated with HAP and HAP/MoS₂NSs nanocomposite and followed for various cellular activities. The cells incubated with HAP@2 shows higher cell adhesion, cell proliferation, and alkaline phosphatase activity (ALP) in contrast to HAP. The in vivo and in vitro results of the increased ALP level confirm that HAP@2 promotes osteogenic differentiation. This improved osteogenesis was validated with upregulation of osteogenic marker viz. transcription factor, RUNX-2 (∼34 fold), collagen-1 (∼15 fold), osteopontin (∼11 fold), osteocalcin (∼20 fold), and bone morphogenetic protein-2 (∼12 fold) after 12 week postimplantation in comparison to drilled. The X-ray imaging demonstrates that HAP@2 implants promote rapid osteogenesis and bioresorbability than HAP and drilled. The outcomes of the present study provide a promising tool for the regeneration of bone deformities, without using any external growth factor.

Poly(propylene fumarate)-based materials: Synthesis, functionalization, properties, device fabrication and biomedical applications

Poly(propylene fumarate) (PPF) is a biodegradable polymer that has been investigated extensively over the last three decades. It has led many scientists to synthesize and fabricate a variety of PPF-based materials for biomedical applications due to its controllable mechanical properties, tunable degradation and biocompatibility. This review provides a comprehensive overview of the progress made in improving PPF synthesis, resin formulation, crosslinking, device fabrication and post polymerization modification. Further, we highlight the influence of these parameters on biodegradation, biocompatibility, and their use in a number of regenerative medicine applications, especially bone tissue engineering. In particular, the use of 3D printing techniques for the fabrication of PPF-based scaffolds is extensively reviewed. The recent invention of a ring-opening polymerization method affords precise control of PPF molecular mass, molecular mass distribution (Ɖ_M) and viscosity. Low Ɖ_M facilitates time-certain resorption of 3D printed structures. Novel post-polymerization and post-printing functionalization methods have accelerated the expansion of biomedical applications that utilize PPF-based materials. Finally, we shed light on evolving uses of PPF-based materials for orthopedics/bone tissue engineering and other biomedical applications, including its use as a hydrogel for bioprinting.

Two-dimensional graphene oxide-reinforced porous biodegradable polymeric nanocomposites for bone tissue engineering

This study investigates the mechanical properties and in vitro cytotoxicity of two-dimensional (2D) graphene oxide nanoribbons and nanoplatelets (GONRs and GONPs) reinforced porous polymeric nanocomposites. Highly porous poly(propylene fumarate) (PPF) nanocomposites were prepared by dispersing 0.2 wt % single- and multiwalled SONRs (SWGONRs and MWGONRs) and GONPs. The mechanical properties of scaffolds were characterized using compression testing and in vitro cytocompatibility was assessed using QuantiFlour assay for cellularity and PrestoBlue assay for cell viability. Immunofluorescence was used to assess collagen-I expression and deposition in the extracellular matrix. Porous PPF scaffolds were used as a baseline control and porous single and multiwalled carbon nanotubes (SWCNTs and MWCNTs) reinforced nanocomposites were used as positive controls. Results show that incorporation of 2D graphene nanomaterials leads to an increase in the mechanical properties of porous PPF nanocomposites with following the trend: MWGONRs > GONPs > SWGONRs > MWCNTs > SWCNTs > PPF control. MWGONRs showed the best enhancement of compressive mechanical properties with increases of up to 26% in compressive modulus (i.e., Young's modulus), ~60% in yield strength, and ~24% in the ultimate compressive strength. Addition of 2D nanomaterials did not alter the cytocompatibility of porous PPF nanocomposites. Furthermore, PPF nanocomposites reinforced with SWGONRs, MWGONRs, and GONPs show an improvement in the adsorption of collagen-I compared to PPF baseline control. The results of this study show that 2D graphene nanomaterial reinforced porous PPF nanocomposites possess superior mechanical properties, cytocompatibility, and increased protein adsorption. The favorable cytocompatibility results opens avenues for in vivo safety and efficacy studies for bone tissue engineering applications. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1143-1153, 2019.