Aim: This study investigates the effects of tungsten disulfide nanotubes (WSNTs) and molybdenum d... more Aim: This study investigates the effects of tungsten disulfide nanotubes (WSNTs) and molybdenum disulfide nanoplatelets (MSNPs) on fibroblasts (NIH-3T3) and mesenchymal stem cells (MSCs) to determine safe dosages for potential biomedical applications. Materials & methods: Cytotoxicity of MSNPs and WSNTs (5–300 μg/ml) on NIH-3T3 and MSCs was assessed at 6, 12 or 24 h. MSC differentiation to adipocytes and osteoblasts was assessed following treatment for 24 h. Results: Only NIH-3T3 cells treated with MSNPs showed dose or time dependent increase in cytotoxicity. Differentiation markers of MSCs in treated groups were unaffected compared with untreated controls. Conclusion: MSNPs and WSNTs at concentrations less than 50 µg/ml are potentially safe for treatment of fibroblasts or MSCs for up to 24 h.
Graphene nanoparticle dispersions show immense potential as multifunctional agents for in vivo bi... more Graphene nanoparticle dispersions show immense potential as multifunctional agents for in vivo biomedical applications. Herein, we follow regulatory guidelines for pharmaceuticals that recommend safety pharmacology assessment at least 10-100 times higher than the projected therapeutic dose, and present comprehensive single dose response, expanded acute toxicology, toxicokinetics, and respiratory/cardiovascular safety pharmacology results for intravenously administered dextran-coated graphene oxide nanoplatelet (GNP-Dex) formulations to rats at doses between 1 and 500 mg/kg. Our results indicate that the maximum tolerable dose (MTD) of GNP-Dex is between 50 mg/kg ≤ MTD < 125 mg/kg, blood half-life < 30 min, and majority of nanoparticles excreted within 24 h through feces. Histopathology changes were noted at ≥250 mg/kg in the heart, liver, lung, spleen, and kidney; we found no changes in the brain and no GNP-Dex related effects in the cardiovascular parameters or hematological ...
Journal of biomedical materials research. Part A, Jan 4, 2014
This study investigates the in vitro cytocompatibility of one-dimensional and two-dimensional (1D... more This study investigates the in vitro cytocompatibility of one-dimensional and two-dimensional (1D and 2D) carbon and inorganic nanomaterial reinforced polymeric nanocomposites fabricated using biodegradable polymer poly (propylene fumarate), crosslinking agent N-vinyl pyrrolidone (NVP) and following nanomaterials: single and multiwalled carbon nanotubes, single and multiwalled graphene oxide nanoribbons, graphene oxide nanoplatelets, molybdenum disulfide nanoplatelets, or tungsten disulfide nanotubes dispersed between 0.02 and 0.2 wt% concentrations in the polymer. The extraction media of unreacted components, crosslinked nanocomposites and their degradation products were examined for effects on viability and attachment using two cell lines: NIH3T3 fibroblasts and MC3T3 preosteoblasts. The extraction media of unreacted PPF/NVP elicited acute dose-dependent cytotoxicity attributed to leaching of unreacted components into cell culture media. However, extraction media of crosslinked na...
ABSTRACT We present a preliminary in vivo study of the microwave-frequency dielectric properties ... more ABSTRACT We present a preliminary in vivo study of the microwave-frequency dielectric properties of mice breast tumor xenografts with accumulation of single-walled carbon nanotubes (SWCNTs). Dispersions of SWCNT-DSPE-PEG at various concentrations were injected directly into 22 tumors. Dielectric properties (1-6 GHz) before and after the injection were characterized using an open-ended coaxial probe technique. Baseline measurements (sham control and PEG only) were also conducted in 12 tumors. We found at least a ~10% relative permittivity enhancement effect upon injection of 100 μl of SWCNT stock solutions at concentrations ranging between 3 and 7 mg/ml.
ABSTRACT In this chapter, selected published articles pertaining to micro- and nanotechnologies f... more ABSTRACT In this chapter, selected published articles pertaining to micro- and nanotechnologies for bone tissue engineering are reviewed with a focus on development of scaffolds. Nanoparticles and nanofibers have shown to improve the mechanical properties of biodegradable polymeric implants. Non-union bone fractures are a major health care concern in the United States. One of the most widely used strategies in bone tissue engineering is the use of scaffolds for temporary structural support. Scaffolds are porous biomaterials and play a central role in tissue engineering approaches by guiding cell proliferation and assisting the exchange of nutrients and waste. Scaffolds made with micro- and nanoparticles and micro- and nanofibers show much promise as they impart the ability to create scaffolds with appropriate mechanical properties and microenvironment. The chapter discusses micro/nanomaterials of hydroxyapatite, a variety of synthetic polymers, and silk, and their potential for use as bone tissue engineering scaffolds.
Recent advances in nanotechnology have enabled the synthesis and characterization of nanomaterial... more Recent advances in nanotechnology have enabled the synthesis and characterization of nanomaterials suitable for applications in the field of biology and medicine. Due to their unique physico-chemical properties, carbon-based nanomaterials such as fullerenes, metallofullerenes, carbon nanotubes and graphene have been widely investigated as multifunctional materials for applications in tissue engineering, molecular imaging, therapeutics, drug delivery and biosensing. In this review, we focus on the multifunctional capabilities of fullerenes and metallofullerenes for diagnosis and therapy. Specifically, we review recent advances toward the development of fullerene- and metallofullerene-based magnetic resonance imaging (MRI) and X-ray imaging contrast agents, drug and gene delivery vehicles, and photodynamic therapy agents. We also discuss in vitro and in vivo toxicity, and biocompatibility issues associated with the use of fullerenes and metallofullerenes for biomedical applications.
Derivatized water-soluble Gd-based metallofullerenes are excellent MRI contrast agents with unusu... more Derivatized water-soluble Gd-based metallofullerenes are excellent MRI contrast agents with unusually large proton relaxivities for agents with no direct Gd-OH2 bonding. In this study, dynamic light scattering (DLS), static light scattering (SLS), and transmission ...
Aim: This study investigates the effects of tungsten disulfide nanotubes (WSNTs) and molybdenum d... more Aim: This study investigates the effects of tungsten disulfide nanotubes (WSNTs) and molybdenum disulfide nanoplatelets (MSNPs) on fibroblasts (NIH-3T3) and mesenchymal stem cells (MSCs) to determine safe dosages for potential biomedical applications. Materials & methods: Cytotoxicity of MSNPs and WSNTs (5–300 μg/ml) on NIH-3T3 and MSCs was assessed at 6, 12 or 24 h. MSC differentiation to adipocytes and osteoblasts was assessed following treatment for 24 h. Results: Only NIH-3T3 cells treated with MSNPs showed dose or time dependent increase in cytotoxicity. Differentiation markers of MSCs in treated groups were unaffected compared with untreated controls. Conclusion: MSNPs and WSNTs at concentrations less than 50 µg/ml are potentially safe for treatment of fibroblasts or MSCs for up to 24 h.
Graphene nanoparticle dispersions show immense potential as multifunctional agents for in vivo bi... more Graphene nanoparticle dispersions show immense potential as multifunctional agents for in vivo biomedical applications. Herein, we follow regulatory guidelines for pharmaceuticals that recommend safety pharmacology assessment at least 10-100 times higher than the projected therapeutic dose, and present comprehensive single dose response, expanded acute toxicology, toxicokinetics, and respiratory/cardiovascular safety pharmacology results for intravenously administered dextran-coated graphene oxide nanoplatelet (GNP-Dex) formulations to rats at doses between 1 and 500 mg/kg. Our results indicate that the maximum tolerable dose (MTD) of GNP-Dex is between 50 mg/kg ≤ MTD < 125 mg/kg, blood half-life < 30 min, and majority of nanoparticles excreted within 24 h through feces. Histopathology changes were noted at ≥250 mg/kg in the heart, liver, lung, spleen, and kidney; we found no changes in the brain and no GNP-Dex related effects in the cardiovascular parameters or hematological ...
Journal of biomedical materials research. Part A, Jan 4, 2014
This study investigates the in vitro cytocompatibility of one-dimensional and two-dimensional (1D... more This study investigates the in vitro cytocompatibility of one-dimensional and two-dimensional (1D and 2D) carbon and inorganic nanomaterial reinforced polymeric nanocomposites fabricated using biodegradable polymer poly (propylene fumarate), crosslinking agent N-vinyl pyrrolidone (NVP) and following nanomaterials: single and multiwalled carbon nanotubes, single and multiwalled graphene oxide nanoribbons, graphene oxide nanoplatelets, molybdenum disulfide nanoplatelets, or tungsten disulfide nanotubes dispersed between 0.02 and 0.2 wt% concentrations in the polymer. The extraction media of unreacted components, crosslinked nanocomposites and their degradation products were examined for effects on viability and attachment using two cell lines: NIH3T3 fibroblasts and MC3T3 preosteoblasts. The extraction media of unreacted PPF/NVP elicited acute dose-dependent cytotoxicity attributed to leaching of unreacted components into cell culture media. However, extraction media of crosslinked na...
ABSTRACT We present a preliminary in vivo study of the microwave-frequency dielectric properties ... more ABSTRACT We present a preliminary in vivo study of the microwave-frequency dielectric properties of mice breast tumor xenografts with accumulation of single-walled carbon nanotubes (SWCNTs). Dispersions of SWCNT-DSPE-PEG at various concentrations were injected directly into 22 tumors. Dielectric properties (1-6 GHz) before and after the injection were characterized using an open-ended coaxial probe technique. Baseline measurements (sham control and PEG only) were also conducted in 12 tumors. We found at least a ~10% relative permittivity enhancement effect upon injection of 100 μl of SWCNT stock solutions at concentrations ranging between 3 and 7 mg/ml.
ABSTRACT In this chapter, selected published articles pertaining to micro- and nanotechnologies f... more ABSTRACT In this chapter, selected published articles pertaining to micro- and nanotechnologies for bone tissue engineering are reviewed with a focus on development of scaffolds. Nanoparticles and nanofibers have shown to improve the mechanical properties of biodegradable polymeric implants. Non-union bone fractures are a major health care concern in the United States. One of the most widely used strategies in bone tissue engineering is the use of scaffolds for temporary structural support. Scaffolds are porous biomaterials and play a central role in tissue engineering approaches by guiding cell proliferation and assisting the exchange of nutrients and waste. Scaffolds made with micro- and nanoparticles and micro- and nanofibers show much promise as they impart the ability to create scaffolds with appropriate mechanical properties and microenvironment. The chapter discusses micro/nanomaterials of hydroxyapatite, a variety of synthetic polymers, and silk, and their potential for use as bone tissue engineering scaffolds.
Recent advances in nanotechnology have enabled the synthesis and characterization of nanomaterial... more Recent advances in nanotechnology have enabled the synthesis and characterization of nanomaterials suitable for applications in the field of biology and medicine. Due to their unique physico-chemical properties, carbon-based nanomaterials such as fullerenes, metallofullerenes, carbon nanotubes and graphene have been widely investigated as multifunctional materials for applications in tissue engineering, molecular imaging, therapeutics, drug delivery and biosensing. In this review, we focus on the multifunctional capabilities of fullerenes and metallofullerenes for diagnosis and therapy. Specifically, we review recent advances toward the development of fullerene- and metallofullerene-based magnetic resonance imaging (MRI) and X-ray imaging contrast agents, drug and gene delivery vehicles, and photodynamic therapy agents. We also discuss in vitro and in vivo toxicity, and biocompatibility issues associated with the use of fullerenes and metallofullerenes for biomedical applications.
Derivatized water-soluble Gd-based metallofullerenes are excellent MRI contrast agents with unusu... more Derivatized water-soluble Gd-based metallofullerenes are excellent MRI contrast agents with unusually large proton relaxivities for agents with no direct Gd-OH2 bonding. In this study, dynamic light scattering (DLS), static light scattering (SLS), and transmission ...
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